So you think you want an MGB or V8?
Body Brakes Clutch Cooling Electrics Engine Fuel Gearbox Heater Ignition Propshaft Rear axle Steering and Suspension Wheels and Tyres
Miscellaneous Downloadable PDFs The sectioned MGB at the British Motor Museum, Gaydon
V8s have a one-piece assembly where the rubber bush is bonded to a steel sleeve to give more positive handling. With these it is important not to tighten the pivot pin castellated nuts until the weight of the car is on its suspension. This is because the outer part of the rubber is a tight fit into the A-arm, the steel sleeve acts as a spacer and is clamped tight by the nut, and so the action of the suspension tends to twist the rubber rather than slide it over the spacer. If the castellated nuts are fully tightened with the suspension hanging down then when the car is on its wheels there is already a lot of twist imparted to the rubber, and when the suspension is compressed over a bump it gets twisted even more. This can tear the rubber to the detriment of handling.
Removal and replacement of the of the A-arms can be found in Front Spring Removal. While apart check the lower trunnion thrust washers for wear as this can cause a clonk when braking.
The steel sleeve is quite a snug fit over the pivot pin and can rust to it. In the past I've had to drill through the rubber to part the A-arm from the pivot, then carefully grind through the sleeve before I could chisel it off. The rubber bonds to the A-arm as well requiring more digging-out. Clean up the pivot pin and A-arm hole with a fine file or coarse emery as required to get smooth surfaces. To get the new bush into the A-arm you may well have to smear it with washing-up liquid or Swarfega Original (smooth), then use a vice to press the new bush in. For full seating you may need to use a large socket that will fit over the bush but bear on the A-arm hole on one side, and a small socket that will bear on the sleeve on the other. Smear the pivot pin with copper grease to aid future disassembly and reassemble the A-arms to pivot pin, washers and castellated nut leaving the nuts a turn or two loose as mentioned above. Lower the car onto its wheels, and only then tighten the castellated nuts and fit the split-pins.
Anti-roll Bars Updated May 2016
Some juggling by the factory as to what size front bar was fitted where and when:
(Optional to 108038)
|CB GT to 315949||AHH7331||5/8"|
|CB GT 315950 - on||BHH882||5/8"|
|RB Roadster to 76||None|
|RB GT to 76||BHH1217||9/16"|
|Roadster & GT 77 on||BHH882||5/8"|
A rear bar was fitted to both roadster and GT for the 77 model year on, size unknown.
The PO fitted one of the Ron Hopkinson handling kits to the V8 in the shape of the rear bar with telescopic dampers and the uprated front bar. It's said that one has to uprate the front when fitting a rear or it induces oversteer. The front bar is 7/8", I've not measured the rear. However when the factory fitted a rear bar for 77 and later models they reused the CB 5/8" bar so that may well just be marketing. For some time I couldn't really tell whether it was making much of a difference (the PO said it did, but he would say that, wouldn't he?) although the back did feel 'different' to my roadster. But whether that was just because I was comparing a CB roadster with an RB V8 I couldn't really say. Then I drove a friends unmodified CB V8 and I could immediately tell it was the same as my roadster i.e. with more movement at the rear as if the rear axle were moving around or the tyres were squirming. But I still didn't know how much of the difference was down to the ARB and how much to the dampers.
February 2016: Gordon Lewis has kindly supplied me with a scan of the original Ron Hopkinson instructions for front and rear, as he has the same set-up as me.
August 2018: Kevin Poole has also very kindly supplied me with a scan of the rear fitting template. The distances on the template are critical of course in order to get the holes in the right places, and to that end Kevin has drawn a reference line exactly 4" long on the template before he scanned them. When you print this template you will have to measure the line to confirm the printed template is to the correct scale. With my printer and software the default settings produced a line that was only 3.75" long on A4 paper, but I was able to change a setting from 'Fit to page' to 'Actual size' (or a custom setting of 100%), and that came out correctly. However one side of the drawing is clipped as it is now too big for A4 paper in my printer. But if you orientate the page correctly this clipping can be on the side with the narrow taper near the 'scissors' symbol as indicated by the grey shading here, which won't affect the positioning of the holes. If you can only print out one of the templates like that (there are separate ones for each corner of the spare wheel well) then after using the template on the appropriate side, and having punched holes through to mark the floor for drilling, simply turn it over and bend the 'Lay on boot floor' section the other way. Do not clip the other side or you may lose accuracy.
Front bar issues:
One day in the V8 I noticed a grinding on full lock and it turned out to be the rim of the wheel rubbing on the bar. Checked the other lock and it had plenty of clearance, so I gave an exploratory tap on the bar with a lump hammer and it moved sideways a little bit. So I tapped it some more until the clearances were about equal both sides. Now the standard bar on both the V8 and 4-cylinders cars have clamps which sit just inside the pivots and bushes which bolt up to the front apron and so prevent the bar moving from side to side, but mine doesn't have any. Either the PO never fitted them or the Ron Hopkinson kit never provided them. However this is the first time in 9 years and 65k miles so perhaps I do them an injustice. The right-hand (where the rubbing was) front damper has also started leaking recently and although it still seems to be damping normally maybe that has had an effect too. We shall see and if it rubs again after I have changed the damper I will have to investigate some clamps.
Summer 2006: Still grinding, and by this time Colin Parkinson had emailed me to use a 1" length of hose of the appropriate diameter split up one side, and a worm clip clamped round that. Didn't have any suitable hose, but I did have an old inner tube I had already cut into, so I used a 6" (or so) length of 1" width of that, wrapped round the bar several times, and then clamped. We shall see.
Summer 2007: No further grinding, so it looks like a successful mod.
October 2016: Still no grinding, and although I've just been made aware that Brown & Gammons do clamps for 3/4" bars (and other sizes) at £20 a pair ... strips of rubber/split hose and Jubilee clips appeal to me much more!
May 2014: MOT advisory on slight play in the V8 front anti-rollbar bushes. Checked the lower joint to the A-arms first but that was fine, then tried the joint between the drop-link and the bar proper and found several millimetres! Took it apart to find virtually no bush left, just a couple of slivers of rubber on the tube and socket. As an after-market bar long out of manufacture I'm not going to be able to get spares, but maybe the bush for the standard bar might fit. Email one of the usual suspects but of course no response. In the meantime I thought it was worth experimenting with one side. Found a bit of hose that is a reasonable fit for both the sleeve and socket, and with a bit of Vaseline, a suitable bolt and washers, can squeeze the three together enough to get the U-fitting at the top of the drop-link over the new bush and insert the bolt. So easy I decided to do the other side as well, and several hundred miles later there is still no play in either.
October 2016 Subsequently I see these bushes from Brown & Gammons. As the drop-link is the same for the standard and uprated bar, I'm assuming the bolt and hence the ID if the bush is also the same. An enquiry may elicit a response as to whether the OD is the same.
I was pondering how best to clamp the two together for welding, but as the alignment of the bar and the bracket is angled, I decided to refit the parts temporarily and tack-weld them in-situ. If the angle was out by even a small amount there would be a constant twisting force on the bush around the pin, as well as the bush in the arm. I placed some pieces of hardboard around the joint to protect surrounding areas from weld splatter, levered the bracket down onto the bar, and applied a couple of welds. They seemed secure to I removed the drop-link and finished the welding and clean-up in the vice, and reinstalled it. While working on this I had noticed that the bush I had replaced in May 2014 showed no signs of wear, so that had been a successful repair.
Would my weld repair hold? If it broke again I would need to replace the drop-link. Initially I thought that as a Ron Hopkinson part spares went NLA years ago, which may mean retro-fitting a standard bar, which would mean removal of the rear bar. But while writing this I realised I had been sent a copy of the instructions, which state that the original drop-links are retained, and so are standard items which does make sense.
June 2016: It did break again, partly down to my welding I suppose, the fact that my welder is more applicable to panels, and the RH front bar is thicker than standard so puts more stress on the drop-links. Ordered Sunday morning it arrived Tuesday morning and only took half an hour to fit, and at £10 didn't break the bank.
October 2017: Checking the near-side damper bolts for tightness (found the off-side were loose and causing a clonk) I found the drop-link broken again! Only 15 months old, but for 12 of those Vee was off the road in restoration, it has only done 1000 miles, 500 of which were some longish trips on good roads. Looked up my records to see it was supplied by Moss, who on their description page today say they are made by the original manufacturer, pull-tested to 3/4 ton.
It's interesting to note that the broken end shows the same minimal weld across barely half the diameter of the end of the bar, with no external signs of welding, so quite possibly a type of spot-weld where the two parts are held together and a very large current passed through the joint, rather than with an arc and adding metal with rod or wire.
I started looking at replacements again, and find the price varies from less than £7 at Leacy and more than £15 at B&G, so a 100% (from the cheaper item) range. Some of them looked like they may have some weld where the bar joins the bracket, so starting with Leacy I asked them if they could have a look at one of theirs. Always very obliging they did, and after a pause he said "There's no sign of a weld at all!". Even more obliging he said that there might be more than one manufacturer, and would ring round the other suppliers to see what he could find.
In the meantime I contacted Moss and explained the situation, when I bought it and the use it has had etc. Although I couldn't find the invoice I do have a record of the date so gave that, and next day I get an apology saying they will send me a replacement. (Better service than B&G who supplied an incorrect release bearing for the V8 but despite it being unused refused to do anything about it having had it more than 12 months). On arrival that seems to be the same i.e. no signs of weld around the join.
I have repaired my original again, this time taking more care over the welding. However now I have the FOC replacement I'm going to see about getting it seam-welded where the rod butts up against the bottom of the bracket, so will have what should be a stronger replacement when my repair fails again.
Why so sure it will fail again? Where I live it is impossible to drive anywhere without going over a series of traffic-calming measures. The full-width tarmac ones are bad enough, but there are a number of the fantastically inappropriately named 'pillows', anywhere between one and five depending where I'm going. These are large rectangular slabs of concrete, one in the middle of each lane, with all four sides sloping straight up to a sharp edge before the flat top. If nothing is coming the other way then I can drive between the pillows, and reduce the effect by half as with the relatively narrow track the wheels are only part-way up the sloping sides, and both wheels go up and down about the same amount. But if there is someone coming the other way I can't do that. Neither can I go straight over the top as the exhaust catches the sharp edge around the flat top in both the MGBs. What makes it worse is that even the entry edge of these stands proud of the tarmac - either the tarmac has sunk a bit or they were never installed low enough in the first place - which makes the problem even worse. So other than waiting until the coast is clear and driving up the middle (and annoying following vehicles), I've been driving with the near-side wheel in the gutter, which means the exhaust clears it. However that tends to push the off-side wheel up and the near-side wheel down, as the rear wheels are still level, which puts the off-side drop-link in compression and the near-side in tension ... i.e. tending to pull it apart! Added to that the PO fitted a Ron Hopkinson rear bar, which apparently necessitates an uprated front bar. So with the uprated front bar there is even more tension on the near-side drop-link, as the bar needs more force to twist it by the same amount. Whilst I can comfortably drive over most of the tarmac full-width strips at nearly 20mph (most of them are in a 20mph zone because of schools) with these pillows especially when I can't drive between them I'm having to creep over them at less than walking-pace, so it's hardly me 'abusing' my suspension. What's really annoying is that some drivers can race over these well in excess of 30mph (20mph zone remember) with impunity, and I've had people overtaking me when I have to slow right down. I complained to the local Council about one of the tarmac strips in the past, as for some reason the rising and falling ramps were only half as long as any of the others, which made them twice as severe and steeper than the guidelines state. They did correct that, so I shall have a go at them about these pillows.
The other possibility is to replace the uprated front bar with an original, which in theory means I would have to remove the rear bar, although when the factory fitted a rear bar they only uprated the front bar from 9/16" to 5/8". However all three times it has broken, effectively meaning no front ARB at all, the only thing I have been aware of on one of the occasions was a noise from the end of the bar hitting the bracket! The other times nothing at all. So for my driving style at least, hardly essential. The original RB V8 item was 9/16" and common to 4-cylinder RB cars, and although it is NLA there might be a possibility of getting a used one.
November 2017: Scanning eBay I find a 5/8" BHH882 bar for sale at £24.95 + £9.95 P&P so go for it. 1/16" thicker than the original RB V8 bar, but these were used on CB V8s, and a full 1/4" less than the existing one. I wonder about the bushes, and there is an ad on the same page for a pair at £5.10 + £1.95 P&P which didn't seem too bad. But when I started looking at the usual suspects they are £1.20 each plus P&P, and I'll see what they are like first (good). No clamps (to stop the bar moving from side to side) shown, and they (21H667 and 668) are NLA (although the 9/16" ones AHH6546 are available). The RH bar never had them but the bodge worked, so I shall just re-bodge the replacement bar. I do wonder whether 1/32" can be shaved off each of the smaller ones though ... I'll also need new mounting bushes, but they also seem to be available - AHH6541 9/16", 1B4526 5/8", and AHH7927 3/4", all of which use the same clamp. Those three do use the same angular clamp, but I had forgotten the RH uses a half-moon clamp! I'll fit the replacement bar using those, but I suspect they will clamp the rubbers too tightly onto the bar and may well squeak, so will get the correct 'straps' BHH2000 in due course. Being a thinner bar I have some hose that will fit with smaller Jubilee clips to prevent the bar moving from side to side, which is neater than the previous bodge using strips of old inner tube.
Getting underneath I did wonder if I would have enough room to manoeuvre the bars out and in over the bottom hose i.e. would there be enough room below the car and to the side, but there was plenty. Getting the new one fitted was a bit of a fiddle. First I couldn't get the bolt through the eye and the repaired drop-link bracket, and had to remove the drop-link to see what was happening. The replacement bar is more bulbous where it sits in the bracket, and was fouling the additional weld going through a hole in the bracket to the end of the bar, filing that down a bit was all that was needed. Next having forgotten the RH pivot bush straps are half-moon shaped whereas the originals are angular, so not a direct fit, I had to use a jack to lift the straps up a bit compressing the rubber to get the bolts started. As the P&P is more than the correct straps, it can wait for a supplier visit. Annoying, as I had already had to order new pivot rubbers and pay a high P&P, buying the two lots together would probably not have cost any more.
February 2018: I couldn't help laughing when I read this in the latest MGOC magazine:
Ron Hopkinson used to be located in Derby but Moss UK in Derby has taken over the distribution. I ordered a pair of drop links and new nuts, together with two bushes and washers which had been lost, one from each side. The rubber bushes being compressible, and with no instructions, I erred on the side of tightness and when fitting the new parts tightened down the nuts quite a bit. I also daubed the parts in Waxoyl to hopefully reduce any subsequent corrosion. Immediately the rear handling was restored and I went merrily on my way. However about 100 miles down the road I had just done a bit of enthusiastic overtaking when I heard a bump, looked in my rear view mirror, and saw something bounding off into the undergrowth. When I checked underneath sure enough the new pin had snapped but this time I had lost both bushes and washers from that side as it had snapped right at the base of the pin and not part way up as before, see the picture on the left.
I got on the phone to Russ at Moss, who asked me to return the broken drop-link, then he sent me a new pin, bushes and washers at no charge saying he wasn't surprised it had broken given the design of the drop-link with its sharp angle. However after the failure of the new drop-link I had a close look at the ARB and realised there is a significant design weakness in the Ron Hopkinson design as a whole and not just the drop-link. If you look at the factory bars where it joins the drop-links you can see there is a joint that allows the drop-link to swivel back and fore freely, and this is important because as the axle goes up and down the angle between the drop-link and the ARB is continually changing. But with the RH arrangement the only movement that can take place is by distorting the upper rubber bushes which themselves are trying to bend the upper pins of the drop-link back and fore. So this time I made what movement there is as easy as possibly by only tightening the nuts enough to fully engage the nylon on the Nyloc nuts. But even sooner this time it seemed, the drop-link on the right-hand side broke yet again, this time while travelling in a straight line but over some undulations.
Another phone call to Moss and another free drop-link, bushes and washers, but this time they sent yellow poly bushes instead of black rubber. These are much harder than rubber so I would imagine they would break the pins even quicker. Fortunately I had enough rubber bushes left for the top and used the yellow ones on the bottom where there is less bending movement. I decided to try and strengthen the pins by welding and grinding at the base to form a radius instead of a right-angle, you can see the before and after as A and B in the picture on the left. I also cut a chamfer into the base of the bottom washer (C in the picture) so that it sat right at the base of the pin and not up on my weld (D and E before and after). Furthermore I have tried to make the bushes more compliant by shaping the inner hole into a cone rather than the original cylinder, in the hope that this would impart less bending force to the pin. Time will tell, but if one of these breaks again then short of coming up with a completely different joint that allows free pivoting of the drop-link to the bar, I shall have to junk it all.
May 2005: Some 18 months and 4k miles later, and prompted by an enquiry from someone else who has had the same failure, they seem to be holding up, and that includes a reasonable amount of using the power and working the suspension. Someone else reported a while ago that they only just nipped up the nuts and have had no problem, but as mentioned above when I did that on the 2nd replacements they broke even sooner than the 1st replacements. An alternative to doing away with a rear ARB altogether might be to fit the factory system recovered off a scrapped car. The joints at the ends of the bar (which freely articulate) could well be worn and loose but I note they are now available again. Another possibility might be to machine the ends of the RH bar to accept the screw-on factory end joints.
February 2018: Gary Roberts and I have been emailing back and fore about the RH kit, and he has found reference to an updated version on the Moss Europe site - Evolution 2 kit EHK101. They are not currently available (and the Moss US part number given does not exist on that site, or this kit) but there are fitting instructions which he forwarded to me. Looking at the drawings and reading the instructions under 'Roll Bar Links' it is evident that rather than the fixing holes for the links - and the studs on the links - both being vertical as on mine, they are now horizontal. This makes them the same as the damper drop-links i.e. relatively free pivots with no bending moment.
Clonk when Braking August 2018
The problem was how to do that while looking round the back of the wheel at the suspension components. I would need a pal, but rather than have him grasp the wheel and heave I decided to make something like the eared spinner 'spanner' which would give more leverage on the wheel and make the job easier. Cut out a template from card held against the spinner and drawn round, marked up some gash board shelving, cut out the shape, and screwed a length of angle iron to it. Applied it to the spinner and sure enough relatively gentle levering reproduced the clonk. While I was at it I thought I'd try the other side ... and the cut-out didn't fit as I had shaped it for the asymmetric spinner on the off-side! No matter, a few minutes later I had a 'universal' spinner spanner, but no clonk from the other side.
While waiting for said pal to arrive I pondered some more, looking at the drawings of the front suspension assembly to see if I could work out what the source might be, and the main contender was the lower king-pin trunnion sliding back and fore on the distance tube. Pal duly arrived, did the levering, and that's exactly what is happening. The distance tube itself is supposed to be tightly clamped between the thrust washers, but there is a rotation between the king-pin bush and the inner faces of the thrust washers as the suspension moves up and down and the king-pin bush pivots about the distance tube. Grease is supposed to be forced into the lower nipple to the inside of the bush, and then spread outwards to the ends, and the thrust washers, to be retained by the grease seal. With the lower trunnion moving back and fore on the distance tube it could be one of several things:
Then cleaning up the thrust washers clearly shows wear marks on the face that has been against the king-pin eye, and they can be felt with a finger-nail. New lower trunnion kit? The rubber grease seals are old but still holding their shape, and it means ordering and waiting for a kit. As there is no wear where the thrust washers bolt up to the distance tube, or to the grease seal support (to be honest I have no idea why the support is there, it's the same size as the thrust washer and flat against it), surely if I just turn each washer round it will present new faces to the king-pin bush? The effect of wear on the (now) back of the thrust washer where it is against the seal support should be negligible. So based on nothing lost if I do that, that is what I do. Pull the trunnion away from the ends of the A-arms, reassemble the seal, seal support and thrust washer against the ends of the distance tube, and slide the trunnion back between the A-arms. Peering through and fine-tuning of the jack height gets the holes aligned to I can get the link bolt back in, and refit the nut. Jack down and heave on the wheel and no clonk. But having been disassembled and reassembled maybe things need time to settle back into position, so take Bee out for a drive. A few miles test braking where I can, and still no clonk, nor some time later on a longer trip!
The trunnion dust seals may need replacement but beware. If they are reusable then I would as replacements have a reputation for failing in a few months. One person claimed one of the suppliers had neoprene versions, but these expanded in use so didn't retain grease and let dirt in, and needed annual replacement. A year later he was recommending them, and when questioned stated that although they are the same part number they have changed and are now better - Moss Europe AAA1323X, Caveat Emptor!
Flushed with success and as it only took half an hour at most, I decide to tackle Vee as well. Hers is less noticeable, and seems to be coming from the near side. Pulling on the wheel reproduces it, I don't have the equivalent of the 'spinner spanner' for her stud-mounted alloys, but then knowing what I know now I don't need it. Vee has a castellated nut and split-pin which takes a few minutes to fiddle out from behind the brake back-plate, but with the thrust washers out they show similar wear to Bee's, although not to the same extent. But turned round, all refitted, and another test-drive, and no clonk! Doubly chuffed.
Steering Column Universal Joint Added August 2010
Note that chrome bumper UJ consists of separate yokes, spider and bearings (needles in a cup) and the spider and bearings can be replaced using the existing yokes. For rubber bumper cars the overall UJ is smaller which precludes component replacement and it has to be replaced as a complete assembly. It don't know if it applies to all rubber bumper cars, or just to V8s, but there is an oddity in the splined shafts that go in the UJ. On the roadster the column shaft has a notch for the clamp bolt meaning it can only go in the UJ one way, and the rack shaft has a groove all the way round meaning it can go in the UJ in any rotational position. This means the two shafts can be assembled in as many different relative positions as there are splines as on the roadster. However on the V8 both column and rack shafts only have the notch, which means the two shafts can only ever be in one relative orientation.
Bee had advisories on both track-rod ends this year. Having a quick look the boots had split on both, and the pin on one was loose in the body so I'm surprised it wasn't a fail. But while checking those I became aware of slop in the column UJ (again!) and that is usually a fail. This will be the fourth replacement, the first (July 1997) failing at the next MOT as the cups were loose in the yokes, but I got a 50% refund on those. The second replacement (July 1998) lasted about eight years and 20k, this one (bought June 2006) six years and 12k. Thinking it could be column and rack alignment, my previous attempts being done with wire pointers as above, and having recently found Moss UK have the alignment gauges, I get the UJ (August 2012), track-rod ends and gauges from Moss.
The UJ change was a fairly straightforward operation - remove the four rack bolts, pull it forwards about an inch or so (he wheels will tor in) and with the column shaft pulled back (early collapsible column inners move in and out a couple of inches) there is enough room to get the UJ assembly off the shafts. Circlips removed and tapping the yokes knocks the cups out, but the new ones need the big vice to press them in, so no problems of them being loose next year! I then go to grease it using the supplied nipple and find it is smaller than standard, so my grease gun doesn't fit. The tapping in the UJ body is also smaller than normal so a standard nipple won't fit that either. Eventually I sort out a solution but in the meantime get on with checking the alignment of the column and rack shafts.
October 2018: Returning from The Beacons Run 'at speed' I'm aware of a slight vibration from the steering wheel - but nowhere near as bad as when the V8 wheels were unbalanced - and investigating shows there is slop in the UJ - again, after six years and just 10k, and despite this one having a grease-nipple I've lubricated each year, so yet another replacement needed. By contrast the different design on Vee - despite 100k with me quite a few of which with significant wheel imbalance and wobble - is the one that came with the car. Replacements can be very variable in price - anything from £8 to £16 from the usual suspects plus eBay. Delivery can be anything from £0 to £11 with some sources having a low item price but high delivery cost, so you need to look at the total price when making a decision. Before replacing that I got the front wheel balance checked.
Alignment: July 2008
It is vital to get this correct or you will get rapid wear of the UJ and rack pinion bearing and possible breakage of the pinion shaft. Play in either is a UK MOT failure, but note that a certain amount of rotational play in the collapsible steering columns themselves is acceptable (my Toyota Celica manual quotes 1/4" at the rim, for example, which is about what my V8 has, but I have had to replace the UJ on the roadster a couple of times even though it only had barely detectable play).
The objective is to get the centre-line of the rack shaft crossing the centre-line of the column shaft at the exact centre of the UJ. It is achieved by shims between the four rack to cross-member mounting points, together with positioning of the steering column within the movement of its mounting bolts. It is necessary because the rack and column shafts sit at different angles in both the vertical and horizontal planes, as well as manufacturing tolerances in the bodyshell and crossmember. The factory used this tool (click thumbnail), note that the different bores were probably because it was a standard tool across a range of BL vehicles, although there are different lengths of chrome and rubber bumper MGBs of which more later. Highly unlikely to be available now, so how do we replicate it? Personally I wrapped some stiff wire around the end of each shaft, with the tip of each wire at a point in space equal to where the centre of the UJ would be when fitted to that shaft. You can get the tip exactly on the centre line by rotating each shaft in turn, if you get any wobble of the tip it isn't aligned, so tweak it until it is stable. Then it is a matter of fitting shims and adjusting the column as required to get the two tips just touching, which could be quite a long process of trial and error. Others have said they used blobs of Blu-Tak or similar. The problem with both of these is that it is very easy to knock the tip of the wire or Blu-Tak off-centre as well as length. Some have said they loosely fit the rack, connect up the UJ, then measure the gaps between the rack casing and the crossmember and fit shims accordingly. Personally I don't think that is good enough on its own as the weight of the rack will be hanging on the UJ to some extent, although it is probably good enough to get a starting point for shims, and trial and error with pointers after that for fine adjustment. Update January 2010: Even worse is a method I've seen where someone turns the steering wheel back and fore while someone else tightens up each rack bolt bit by bit, till the steering wheel binds, then that bolt is slackened a bit, a section snipped out of a washer so it can be slid on the bolt, and that bolt tightened. That is so crude, the UJ will surely start binding way before you can feel any resistance at the steering wheel, hence still be binding when it is backed off a bit and the washer tightened. Besides which the washers that were shown were way thicker than any shim I have seen. Definitely from the "If it isn't bodged it won't work" school of engineering.
Updated January 2011:
The later energy absorbing column has one bracket under the dash with three bolts, and the bottom of the outer tube has a loose plate with three bolts screwing it into the firewall. It's been said that this bottom plate and its bolts are to align the column but that is not the case. They simply clamp the loose plate on the bottom of the shaft, via a gasket, to the toe-board and are solely to seal the body aperture against water, noise and fumes ingress. All the alignment must be done by sliding the column on the upper three bolts for in and out adjustment, swivelling it sideways for horizontal adjustment, and by shims between the column and the body bracket, and the rack and the cross-member brackets as required, to get the correct vertical alignment. It's only when alignment is complete you tighten the toe-plate bolts. With all columns if you remove or alter the column even if you haven't altered the rack you will need to recheck the column alignment before tightening the column bolts. Note that for the earlier columns the inner shafts are free to slide up and down and will automatically take up the correct position when the UJ clamp bolts and rack mounting bolts are inserted. This is not the case for the later energy-absorbing column, where its in and out position must be carefully set with the gauges, in order to get the correct spacing of the shaft cut-outs, so that the UJ and rack bolts can be refitted.
As far as using gauges goes my Haynes is completely wrong here, saying as it does that the rack and column should be fitted before installing the alignment gauges. This simply cannot be done, the two have to be moved apart a couple of inches to get the gauges onto the shaft, and off again to refit the UJ. With the gauges on adjust the column position and the shims as above to get the correct alignment. However my Leyland Workshop Manual also has a major error in the section for the later energy absorbing columns, in that it tells you "Slacken the screw on the column point gauge and slide the gauge down until the points of both gauges are on the same plane but not overlapping". The whole point of the gauge screws with this column is that they must screw into the cut-outs in the shafts, and the whole column must be slid up and down to get the points to just touch. Unless you do this it is highly likely that you will not be able to get the second UJ clamping bolt inserted, or the rack bolts refitted, whichever you do last. This isn't the case with earlier columns, where the whole inner shaft is free to slide up and down inside the outer. With those the shaft will automatically take up the correct position. I repeat, with the later energy-absorbing column you can only adjust the up and down position of the inner, and hence get the cut-out in the correct place for the UJ, by moving the whole column on its upper bolts (which is also why the toe-plate must be able to slide up and down on the column outer). It also tells you to fit the rack after the column, and after the gauges have been fitted. Ok if you have both off, or just the rack, but not if you have only had the column off. It makes more sense to fit the gauges before the column is reinstalled, rather than fit the column, pull the rack, fit the gauges, refit the rack, align, then have to pull and refit the rack again in order to remove the gauges and fit the UJ. Additionally towards the end of the process it tells you to replace the gauges with the UJ, then fully tighten the two upper bolts, then measure the gap at the third bolt, and fit shims accordingly. This makes no sense to me. Better to align, fitting shims as required to the third bolt and fully tightening all three to get the correct alignment while the gauges are still on the shafts. And only then pull the rack forwards to remove the gauges and fit the UJ, and refit the rack. Unlike the column, the rack (with its shims) should always go back in the same position. Whereas if you are only fitting shims to the third column bolt and fully tightening that after the UJ is installed, you could be affecting the vertical alignment. This is why it makes more sense to fit the gauges before installing the column, leaving the rack where it is until the very end of the process, only finally pulling the rack forwards to remove the gauges and refit the UJ. Note that if you raise the front wheels off the ground you only have to remove the four rack bolts, leaving the track-rod ends attached to the steering arms. As you pull the rack forwards to allow you to remove the gauges and fit the UJ, the wheels will simply go 'pigeon-toed' i.e. turn in towards each other. However I have found that with the earlier columns where the inner will slide up and down relative to the outer, it is possible to withdraw the inner enough to remove both parts of the gauge, which means you don't have to disturb the rack. As mentioned above it is the position of the rack and the fitting of the UJ that determines the final position of the column inner relative to everything else.
Some time later I came across a web page by Simon Jansen in New Zealand who had fabricated his own alignment tool and gave the dimensions he used, see here and scroll down to January 2006. This topic comes up on mail lists and BBs from time to time and I had posted links to Simon's site. Recently someone came back querying the 29mm dimension from the centre of the notch in the shafts and the tip of the tool, saying his was more like 33mm. I passed this on to Simon, and he said it was possible as his car was a mish-mash of components as it was a conversion from rubber bumper to chrome and from LHD to RHD. I measured a new RB V8 UJ as carefully as I could and also came up with 33mm, with 45mm for my chrome bumper roadster (measured on car) and posted this as a warning with the link I already had on this site to Simon's page.
Some time after that Kelvin Dodd of Moss US posted this link to a replica tool available from Moss. It's curious that it seems to come with two sets of screws, as it would need two sets of holes to be suitable for both chrome and rubber bumper cars, which would need only one set of screws. I asked Kelvin if could confirm whether there were one or two sets of holes, and what the distances to the tips were. He came back with the information expressed slightly differently as being an overall length of 2.11", one hole 0.336" from the open end, and another hole 0.936" from the open end. The bore is 0.744+-0.005/0.002" or 18.9mm (slightly smaller than Simon's 19.3mm), and the hole depth is 1.70". Converting this to distance from the tip and millimetres I get 1.174" or 29.82mm for one hole and 1.764" or 44.8mm for the other, and this is where it gets curious. The Moss 29.82mm is pretty close to Simon's 29mm, and the Moss 44.8mm is very close to the 45mm I measured on my CB roadster. However my RB V8 UJ measures 33mm, which is the same measurement that the person who queried Simon's dimension in the first place, and looking in the Parts Catalogue there are only two part numbers for UJs for all models, years and markets i.e. one for CB and one for RB.
So I've re-measured my new RB V8 UJ more carefully, and still get around 1.2415" which equates to 31.5mm, so the Moss 1.174" or 29.82mm remains a mystery (Simon's original 29mm less so as his car is much modified). If making a tool for yourself you will need to check your UJ dimensions very carefully.
Update March 2010: Just been made aware of the identical alignment tool at Moss Europe. The good news is that it is only £7.65 (£16.50 in Sep 2017) as opposed to $24.95 when the exchange rate is 1.5 i.e. $12 or £16! The bad news is that they insist on you ordering at least £10 of parts, before they tell you the shipping costs.
Update August 2010:I get the Moss gauges with a replacement UJ and track-rod ends, so measure them myself, at 44.58 for the CB and 30mm for the RB and all V8s. The latter UJ is 31.5mm, and as that column has a fixed shaft this means that a small gap has to be left between the tips otherwise you cannot get both clamp bolts through the UJ. Doesn't matter for the earlier columns as the inner slides in and out to suit. As I've got to change the steering column UJ, and the rack has to be pulled forward for that, it's a good opportunity to check the alignment at the same time (which is why I bought the gauges with the UJ ...).
The gauges are a nice snug fit on the shafts which is good, and one thumbscrew in each gauge going into the shaft groove holds them firm. The tips are about 1/8" out, part horizontal and part vertical, which could have contributed to UJ wear, but there is some up and down and side to side play in each shaft so the end result would have been not much by way of sideways forces on the UJ. I'll need to adjust the sideways misalignment at the column mountings, so I opt for seeing if I can get the vertical alignment corrected there as well, rather than fiddling with shims at the rack. This style of collapsible (not the later full energy-absorbing) column used on UK 72 and 73 models is supported by two body brackets, one up by the dash and another one further down under the shelf.
Both are slotted so each mounting can move up or down independently giving quite a large change in vertical position of the UJ end of the column shaft. I find the top can go up just a little bit and the bottom down, which puts the gauge pointers in perfect vertical alignment. For horizontal alignment the lower bracket has two bolts up through the heater shelf (with support clips for brake and clutch pipes and harness) and with the nuts slackened the bracket and hence the UJ end of the column can be moved from side to side. With this column the inner can slide up and down freely so you need to pull the wheel up a bit while moving the column, as if the gauge points overlap they will jam and possibly get damaged. Then it's unbolt the rack again and pull it forwards as before to remove the gauges and fit the UJ, lining up the splines by eyeballing the front and rear tyres each side to get to get the steering straight, then fitting the UJ with the wheel in the straight-ahead position, and finally bolt the rack back down. The UJ only attaches to the column shaft in one position as the cut-out for the clamp bolt is cut straight across, but the rack shaft is cut all the way round (oddly the V8 only has notches in both shafts). Really I should have put a paint-mark on the rack-shaft in line with the slot in the clamp before removal, but as I've got to change the track-rod ends as well and then get the alignment checked, it'll come straight in the end.
Front Damper Replacement Updated October 2009
When changing a damper for the first time you will almost certainly need a new link bolt and nut and bushes, as each one I have done has had the pin corroded solid with the inserts in the bushes. In both replacements I have done the link bolt was supplied with a Nyloc nut instead of the original low-profile castellated nut and split-pin. In neither case was the bolt long enough - or the nut low-profile enough - to be fully tightened - with a Nyloc nut there should be about three threads clear of the bolt, but the bolt barely reached the Nyloc let alone go through it. Fortunately the bolts were drilled for a split-pin and I had a suitable low-profile castellated nut in each case. Do not use a Nyloc nut without there being at least three threads visible with the nut fully tightened, the bolt could come out in use. Before paying for dampers check they move smoothly (and heavily damped through their full travel and back to the centre, then wiggle the arms up and down near the centre and make sure there is not slop as they change direction. Exchange dampers where you return the old one is much cheaper than buying new, and the rebuilt replacements are usually of reasonable quality. But as the rebuild is only as good as the original it is possible to get a duff one that fails after quite a short period, however it is still much cheaper to have to change it again fairly soon than to buy new. Out of three replacement lever-arm dampers I had to change a rear one for a second time after only a year or so, its replacement and the other two have been fine. At the time of writing I have just replaced another one so the jury is still out on that. Update October 2009 Annoyingly that started weeping after a year or so, but lasted a further couple of years and MOTs before it got bad enough to start dripping on the floor, which was when I changed it again. Hopefully better luck this time.
Raise the front of the car by jacking under the rear edge of the cross-member (if you jack further forwards than that it will slide further forward in a series of sudden and noisy movements which is a bit disconcerting. Place axle stands under the outer edges of the spring pans, and lower the jack just enough to lift the damper arms off the rebound rubbers. It is important to do this otherwise when you remove the top link bolt the axle assembly and hub will shoot downwards as they are under significant spring pressure.
Next comes removal of the top link bolt connecting the damper arms to the swivel axle. Easy to say, much harder in practice. The bolt runs through the arms of the damper and steel sleeves in the rubber bushes. It is a snug fit in both and unless it has already been replaced fairly recently or was assembled using Waxoyl and copper grease it will almost certainly be well rusted to both. The rubber bushes will probably also have deteriorated and be bonded to the eye in the swivel axle. In two replacements on may cars this has been the case and I have had to hacksaw through the bolt both sides of the swivel axle eye. On a second replacement of one of them everything came apart very easily.
Remove the nut on the end of the link pin, it is usually castellated with a split-pin. Slacken right off the clamp-bolt holding the two arms of the damper together, and drive a wedge between them to lever the arms apart and give you more room to cut through the link bolt.
Use a length of cable or whatever to tie the swivel axle to the bracket of the bump and rebound rubbers to prevent the axle falling outwards and stressing the brake hose when the link pin has been cut through or removed.
You can try driving the link bolt out of the bushes and arms, but it shouldn't take much hammering to realise it isn't going to shift. If not, cut the flange off the end of each bush by chiselling and cutting at an angle into the eye of the swivel axle. This reveals a section of link bolt on each side to cut through without damaging the inner faces of the old damper (which might then be rejected as a core replacement) or the swivel axle eye. Use a hacksaw where you can turn the blade at 90 degrees to the frame and this should allow you cut inwards and upwards each side. With a decent blade it shouldn't take many minutes to cut through both sides, and the damper arms can be lifted up from the swivel axle eye. Remove (it really should be that easy) the four bolts securing the damper body to the cross-member. I use a universal joint between the ratchet and socket, it gives that extra depth for all four bolts and a bit of angle for the back ones where the inner wing curves over them. Lift the damper away - it is heavy!
Now you have to drill, cut, twist and hammer the old bushes and remains if the link bolt out of the swivel axle eye, they will probably come out as a single piece, which can only be done if you have previously removed the flange from the bushes as previously described. Remove any lumps of rubber that are stuck in the eye as this will make insertion of the new ones more difficult.
Check the fluid level in the damper now, it's easier. If you find you have to add a lot, or in any case after transportation where they may have been at a different orientation to when fitted to the car, work the arm up and down it's full travel several times to expel any air from the valves. Remove any dirt or grit from the cross-member where the damper will sit. At this point I put a bit of copper grease into each hole in the cross-member, then put the damper in position. Coat each bolt with copper grease and insert just a few threads, don't tighten them any more than that until all four bolts are started. Again slacken the clamp-bolt holding the two arms together and wedge the arms apart to fit over the bushes. This is necessary when leaving sound bushes in the swivel axle, not just for new ones.
Coat the outside of new bushes and the inside of the swivel axle with Waxoyl and insert the bushes. They will probably be much wider than the gap between the damper arms even if they are wedged apart. You can either put one or more large nuts over the threaded end of the link bolt then tighten its nut to squeeze the bushes fully into the eye or use a small sash-cramp or something similar. Eventually you should be able to get the bushes far enough in and the damper arms far enough apart to fit the two together, but before you do so put some copper grease inside the steel sleeve of each bush, wiping off any excess from the rubber.
Place the damper arms over the bushes, put more copper grease in the holes in the arms and on the link bolt. Tap the bolt through the appropriate damper arm the bushes, and the other damper arm. Note that the bolt has a special round head with one flat which engages with a recess on one damper arm. This is the front arm on the right-hand side, the rear arm on the left, therefore the bolt can only go in one way each side. Things might need a bit of wiggling about while you are tapping to get everything lined up.
Note where the split-pin hole is in the bolt and fit and tighten the nut (40ftlb). This has to clamp the damper arms onto the ends of the bush sleeves, and the inner ends of the bush sleeves together, so it does up tight. The final position of the nut should allow insertion of the split-pin, of course. Refit and tighten the damper arms clamp bolt (28 ft lb). As the four mounting bolts allow a little wriggle-room for the damper now is the time to use it to try and correct any tendency to pull to one side or the other on a flat and level surface (note a normal drainage camber will cause the car to pull to the kerb side slightly). Pulling to one side or the other is caused by unbalanced camber, not by tracking as many think. Which ever side the car pulls there is more camber that side than the other, so pushing the damper arms forwards as you tighten the four bolts (43-45ftlb) will tends to reduce it, and pulling the damper arms backwards on the other side will do the same. It may not do much but is worth a go while you are at it. Refit the wheel and away you go. Inspect the new damper from time to time in the early days just in case you have got a duff one, and always before an MOT.
Rear Lever-arm Dampers August 2009
The damper, drop-link, rebound rubber and bump-rubber pedestal (and for that matter spring) must be treated as a set for correct and safe operation of the rear suspension and these vary from model to model. Whilst the damper obviously controls the rate of spring compression and expansion through the normal working range, the compressed limit is controlled by a pedestal on the axle hitting a bump-rubber under the floor, and the expanded limit is controlled by the rebound strap which is fixed between a body and axle. The final component is the drop-link between damper arm and spring/axle assembly. In an ideal world the spring, in it's normal working position, will position the axle about mid-way between the fully compressed and fully expanded positions, and the drop-link length should be such that the damper is also about mid-way in its travel. The loading on the car could be a little as a single occupant, or it could be two people plus tools and luggage with the consequent compression of the spring, so maybe a median between these two is chosen by the designer as the 'central' position. Whatever, it is vital that the drop-link, rebound strap and pedestal are installed as a set so that it is the rebound strap and bump rubber that provide the limits to axle movement and not the damper itself. Get these wrong and the damper will suffer damage. In theory it doesn't matter as much if the spring varies in set or hardness, as the other components will limit axle travel regardless and so protect the damper. But if the spring is too soft or flat you will be hitting the bump rubbers over relatively small bumps (been there, done that, extended the shackles) or at the other extreme the car will have a very tail high ("submissive monkey") stance and be hitting the straps relatively easily. Whilst hitting the bump-rubbers is merely uncomfortable, continually 'hitting' the rebound straps will eventually break them, and then you will start hitting the damper limit and damaging that.
Chrome bumper 4-cylinder cars had one set of drop-link, rebound strap and pedestal, chrome bumper V8 had a different set, and all rubber bumper cars had a third set in this case the same for 4-cylinder and V8. I know chrome bumper V8s had a higher ride height to 4-cylinder chrome bumper cars to improve the exhaust to ground clearance, utilising a different front cross-member that was later commonised to all rubber bumper cars. The rear spring hangers were lowered at the front and the rear on all rubber bumper cars i.e. 4-cylinder and V8, but they differed between chrome bumper 4-cylinder and V8 cars as described here. Hence all rubber bumper cars have the same damper and axle movement limiting parts, even though the V8 springs are harder. The combination of parts for each model from the Parts Catalogue is as follows:
|Armstrong catalogue||BL catalogue||Drop-link||Rebound strap
||4-cyl chrome bumper||8178LH/RH||GSA168 LH 169 RH||97H 2031||AHH 6355
||V8 chrome bumper||10801LH/RH||GSA328 LH 329 RH||37H 8075||BHH 989
||4-cyl rubber bumper|
|12012LH/RH||GSA368 LH 367 RH||37H 8778||BHH 989
||V8 rubber bumper||12012LH/RH||GSA368 LH 367 RH||37H 8778||BHH 989
||4-cyl rubber bumper|
|12075LH/RH||GSA368 LH 367 RH||37H 8778||BHH 989
Peter Caldwell of Wisconsin posted the following information on the MGCars BBS as part of a thread on this subject in December 2006:
Rear Damper Replacement Added October 2009
Ostensibly two nuts and three bolts, but it can still be a bit of a bear to remove. If you haven't changed them before the nut (11/16") will likely be corroded to the drop-link pin in the damper arm, and nut and pin will turn as one. With units that haven't been on long and correctly assembled with copper-grease the nut will probably come undone but you won't be able to break the taper between pin and damper arm. Fortunately it is easy to remove the damper complete with drop-link and spring bottom plate and deal with them on the bench.
Important - chock the front wheels. Slacken the road wheel nuts a smidgen if the handbrake isn't up to much. Support the car at the front spring eye or hanger on axle stands by jacking under the axle or spring bottom plate. Lower the axle until the car is resting on the stands, then remove the road wheel. Continue lowering the axle to give you more room to work, but observe the condition of the rebound straps before trusting the full weight of the axle to it. Remove the nuts (11/16") and spring washers from the bolts (5/8") holding the damper to the chassis rail, turn the bolts to free them up, but leave them in-situ for the moment.
Undo the U-bolt nuts (9/16" deep socket), which will allow the spring to push the bottom plate and damper drop-link fully downwards. If necessary jack under the spring one side of the bottom plate or the other to raise the spring off the bottom plate and so take any tension off the damper to chassis rail bolts. Supporting the damper remove the chassis rail bolts and lower the whole assembly down off the ends of the U-bolts and away from the car.
With rusted drop-link nuts I had to hacksaw at an angle part-way through the nut then chisel the cut open to free the nut. Because the pin had been turning in the damper arm this came out relatively easily. Where the nut came undone I left it screwed on so that the outer face of the nut was flush with the end of the pin, supported the bottom of the arm or plate on a solid object, and struck the end of the nut and pin to free the taper.
Check the fluid level in the new dampers before fitting. If you find you have to add a lot, or in any case after transportation where they have probably been lying down, work the arm up and down it's full travel several times to expel any air from the valves. Push fit the bolts to the chassis rail, noting that later cars have the 'outer' bolt head in a recess in the wheel arch to give better clearance for the wider tyres on GTs and particularly V8s, and this bolt is shorter than the other bolt. Offer up the damper to the bolts and fit the lock-washers and nuts. Fit the bottom plate with drop-link over the ends of the U-bolts and loosely fit the nuts, then position the damper arm so the drop-link pin can fit through it and fit its washer and nut. Tighten all nuts (55-60 ft lb for the damper to chassis rail nuts).
Hydraulic Damper Fluid Added November 2009
Internal Valving January 2015
I'm Sven from Germany and I'm restoring an MGB GT and converting it to electric drive. I write to you because I cannot find information on the setup of the Armstrong shock valves, and in this forum you are referred to as being the specialist on these. There is nobody here in Germany and Europe who can tell me which are the exact parts for original front and rear shock valves. Disassembling several valves revealed different setup for left and right shocks even for reconditioned pairs fresh from the counter... Let me give you a short overview:
|Sven, There ARE different valve designs that vary by the generation of casting by Armstrong. Remember, the same design was made by Armstrong from 1962-1990. There were many small differences in the valve as determined by the small changes in the castings. We hope that Armstrong made the valve changes based on damping characteristics they could test on a dyno. I can't tell you what should be in the castings you have, but I CAN tell you not to over think this. It doesn't make a huge difference from a street driven perspective. We do make an externally adjustable shock that may interest you as you try to find the best spring rate for your application. Peter|
And thanks for your quick reply. Your statement 'It doesn't make a huge difference from a street driven perspective' helps a lot, because with my EV conversion I will drive 95% in the city and the top speed will not exceed 110 km/h. So I'll just keep an eye on assembling the right hand valve identical to the left hand valve.
Thank you again and best regards,
|You want to be sure that the main valve body, the part with the hex nut, is correct for the casting. 1 takes an o-ring with washer, and 1 without. There is a depth difference, too. Good luck. Peter.|
|Okay, so I will also have a close look at the cast bodies of the shocks...|
Telescopic Dampers - or "Nix to Spax" April 2006
The replacements lasted for many tens of thousands of miles (no more than one should expect) but I had been aware for a while that the ride was getting quite bouncy, especially over humps and dips. The USP of the Spax is their adjustability, but unless you have them on the softest setting they give a bone-jarring ride, and many testify to this. Thinking that they may have 'softened up' over the 70k or so miles they have been on the car (which itself is a poor 'feature') I tried turning the adjusters, but needless to say they had seized, and I decided that I would not replace them when the need next arose but go back to lever-arms. However I was concerned that if one should fail, unless I splashed out again for a replacement (or possibly a pair), I might have to take the V8 off the road for a time while I sourced a pair of lever-arms together with the drop-links and bottom plates. So at the 2006 Stoneleigh MG Spares Show I was on the lookout and managed to pick up the whole lot minus one bottom plate for a tenner, and got a used bottom plate from elsewhere for another fiver. They were already assembled but I wanted to part them for cleaning and painting, but as usual (IME) the nuts had seized. TIP: Careful hacksawing as far as I could through the nut without cutting into the studs (OK, I just nicked the threads, but that won't affect its strength) then using a cold-chisel to open up the cut cracked the rust and it came undone. Using heat is inadvisable is it is bound to damage the rubber bush the stud is mounted in, which is not a replaceable item. That left me needing a couple of nuts, which being Imperial are not that easy to come by. Popped down to my local Halfords where the chap who usually MOTs all my cars had a root through his toolbox and came up with exactly what I needed (That's another pint I owe you ...).
I then discovered that despite measuring two lengths of drop-link at the show, and thinking I had got the longer V8/rubber bumper items (10 5/16" pivot pin centre to pivot pin centre, thanks Graham), I actually ended up with the shorter CB items (8 3/4"). Only discovered this as part of an email thread with someone else, who had the longer ones and needed the shorter! Sadly he was in America so a swap was out of the question. Rather than buy another pair I decided to try 'cutting and shutting' them to extend them (as I had with the rear shackles on the roadster) by the required 1 1/2" or so. Looking round the garage I found a couple of front suspension bottom trunnion bolts that were the correct (0.5") diameter and did the necessary cutting and welding. Two coats of Hammerite smooth on them and the bottom plates and they were ready to go on.
I was quite surprised to find the U-bolts and the nuts and bolts holding the top brackets to the chassis all came undone quite easily as they had not been touched in my ownership, likewise the replacements went on straight-forwardly, the whole job only taking a couple of hours. TIP: The only thing to be aware of is that the two bolts holding each damper to the chassis rail are different in length by about 1/4", which could cause you some head-scratching if you get them mixed up and the two shorter ones on the same side. At some point the forward bolt was recessed into the chassis rail to give more clearance for tyres, possibly for the wider tyres on GT and V8, the shorter bolt goes in this position.
Took the car for a test drive and immediately noticed that on 'normal' surfaces the ride seemed exactly the same but over humps and dips there was no bounce, just a more appropriate firmness without harshness. The standard lever-arms have a two-stage valve that gives relatively mild damping with short movements and harder damping with larger movements, something I have never seen attributed to telescopics of any type. I was deliberately taking the car over as many speed humps as I could find, and going at them progressively harder, when I actually broke one of the welds. It was my fault, when doing the first one I became aware that I was feeding the wire too quickly, which tends to form bobbles of weld on the surfaces of the two pieces being joined rather than fusing them together. No matter, 1/2 hour to take the broken drop-link off, clean up the joint and re-weld, but this time I slipped the spacer tube from the aforementioned bottom bolt (exactly the right internal diameter) over the shaft first, then welded the shaft, then positioned the spacer tube so it covered both welds, and applied more weld between spacer and shaft. Repainted, refitted a couple of days later, and so far so good.
Measurements: A huge variation 'on the road', as it were:
|Axle Type||Wheel Type||Length||Rear Track||Front Track||Note|
|Banjo||Wire||44.5"||49.25" (1250mm)||49.25" (1250mm)||1|
|Disc||46.25"||49.25" (1250mm)||49" (1244mm)||1|
|Rostyle (late)||48.5"||49.75" (1264mm)||48.5" (1247mm)||3|
|Rostyle on V8||48.5"||1252mm||1254mm||5|
|72 spoke wires||47"||1250mm||1220mm||7|
|60 spoke wires||47"||1256mm||-||8|
In the meantime I've done a measurement between wheel mounting surfaces using my tracking gauge, which comes out at 1320mm.
More information on wheel sizes and offsets/insets here, and on converting from stud wheels to centre-lock here.
May 2017: Following a comment on the MGOC forum I learnt that there have been two types of steering arm and track-rod end. What the Workshop Manual describes as 'early production cars' had a washer under the nut securing the TRE to the steering arm. Later cars had a narrower hole in the arm, the TRE pin was longer, and the nut is deeper. Originally there was a washer fitted under the nut, the later items have no washer. But the later TREs can be fitted to the early arms, just leave the washer out. The change must have been pretty early as there is only one RHD and one LHD part number for chrome bumper TREs and one (per side) for steering arms in my Parts Catalogues. The catalogue does list five part numbers though:
Dust covers: Damaged dust covers are apparently an MOT failure, and are available separately, but like so many parts these days - rubber in particular - fail very quickly. Someone on one of the fora claimed he had silicone rubber and they are much better but didn't give a source at the time. Googling revealed only one source - an eBay seller in Bulgaria, but the size quoted is much bigger than quoted elsewhere for non-silicone rubber for the MGB and I couldn't find them elsewhere in his 'shop'. Subsequently the poster came back with a link to the correct (but see below) size 13-31-23, from said Bulgarian source.
Finding one of the covers on my RB V8 slightly damaged with the larger retaining spring distorted I took the dust cover off to check the sizing, and find it significantly different: The pin is 11.6mm diameter, the groove in the socket is 30.33 dia, and the depth between the socket groove and the start of the straight section of the pin is 16.6mm. The existing dust cover is very similar to those measurements for the pin and socket groove, and the depth is 18.8mm. So although the two diameters of the 13-31-23 are quite close the depth is quite a bit more, and the excess material would end up being crushed and maybe not lasting very long. The closest the supplier has is 12-31-21 in 'high quality rubber' but clicking on that displays an error page, and it also looks to be a completely different shape. The next closest is 12-31-22 with the same shape as the existing ones, but is described as 'polyurethane', and priced in American dollars. I am awaiting a response from the supplier. Update: As with so many people these days he seemed unable of answering several questions asked in one email, saying all types were available. Googling showed up other sources but 'universal', and rubber, so I ordered a pair of the poly ones and will see how I get on. Retaining springs not available, but by disconnecting the TRE from the steering arm I was able to remove the cover and retainer (flat, not round wire as with the smaller retainer), 'straighten' the retainer and refit with one of the replacement covers. Some say they use cable-ties, but even the small ones are quite a bit bigger than the springs. Fine on track-rod gaiters, but on these I'm not so sure.
12 months later still there and no signs of deterioration.
A tip when disconnecting the track-rod ends from the steering arms. The nut is usually a Nyloc, and the effect of this is that once the taper is broken turning the nut just turns the pin with it unless you lock the taper again, as otherwise the stud just turns the ball in its joint. And if using a screw-type splitter you really need to have a nut on several threads to avoid damaging the end of the stud. The tip is before cracking the taper remove the Nyloc nut, then put a plain nut on until the end of the stud is close to the face of the nut, then use the splitter. As long as the threads are good the plain nut will be much easier to remove once the taper is broken. For replacement the same problem occurs, so screw the plain nut up tight to lock the taper, then replace with the Nyloc nut.
If changing track rod ends and they are basically the same length alignment marks and counting turns will probably get you close enough to drive straight (hopefully!) to an alignment centre, which should be done as there are bound to be dimensional differences between old and new track rod ends. However changing Bee's track-rod ends I found the new ones were quite a bit longer than the old, so no point. I measured the difference as best I could at 6mm, then screwed the lock-nuts back towards the gaiters until there was a 6mm gap to the ends of the old track-rod ends, and removed them.
The old ones were surprisingly bad given they were only advisories, the worst had lost a large part of its rubber boot, the ball was sloppy in its joint and rusty. The other one had a split boot and was rusty inside, but the ball wasn't as loose. I then screwed the new ones on right up to the lock-nuts. Not happy that I had got the tracking close enough for driving to the alignment place I decided to make an alignment gauge. Having (hopefully) got the tracking close enough for a test drive it was immediately noticeable how smooth the steering was, I had recently been aware of some vibration through the wheel, which wasn't consistent so I didn't think it was wheel balance. Also quieter, as if I had subconsciously noted some rattling, both must have been coming from the worn UJ as well as track-rod ends. I suppose it is a case of not noticing gradual changes in sound and feel over a long time, whereas we should all be aware of sudden changes and either know what they are (as in this case) or investigate them - Nory's "Listen to your car, it is talking to you".
Just after replacing Bee's I find that Vee's need doing as well, as a result of investigating a clonk when applying and releasing the brakes, which led me to discover a clonk as I turned the steering wheel back and fore with the road wheels on the ground, which felt like it was the track-rod end but could be the rack! But this time the offside at least looks heavily corroded. I buy two more track-rod ends plus lock-nuts as it looks I might have to use an angle-grinder on both. I don't have a spanner that fits, and my mini-Stilsons isn't giving me enough leverage as well as chewing up the nut, so a trip to Halfords with a new nut gets me a 22mm which is a pretty close fit. That gets the nut turning on the track-rod, but the track-rod is stuck fast in the track-rod end. My Stilsons grip the track-rod to some extent, and a large ring-spanner over the end of the handle gives me more leverage, but being round bar eventually it just slips, even having applied Halfords 'shock and oh' releasing fluid ('shock' from the freezing spray as well as the penetrating fluid, 'oh' from the 'oh bugger' when it doesn't make any difference). So nothing for it but to run the angle-grinder along the length of the track-rod end until the tips of the threads just start to appear. Get the Stilsons on the track-rod again, hoping the heat from the angle-grinding might have done the trick, with more freezer spray on the exposed threads, but still no go. So this time I put the Stilsons on the end of the track-rod end, pin still in the steering arm, in such a way that it is trying to peel it open, and finally hear a 'crack'. After that it comes off relatively easily, only took a couple of hours... New and old look to be the same lengths, so count the turns to remove (21) and fit the new one (with copper-grease!). I decide to leave the old nut on, screwed back a bit, plus a new one, thinking that in future the two nuts locked together will give me more purchase to turn the track-rod.
When I come to do the second one I don't have much time but put the spanner on the locknut just to see what happens and it moves straight-away. Not only that it is screwing the track-rod out of the track-rod end. So crack the taper to the steering arm, unscrew (18 turns), and screw the new one on. This one already has copper-grease on it, I'd forgotten I had already dealt with that one some years ago when replacing a gaiter. Shows just how effective the grease is, and second nut on the other side obviously not required. This one takes me 10 minutes start to finish! All I have to do now is check and adjust the tracking with my gauge. Well, I say 'all', but having gone from king-pins to track-rod ends and noticing a broken bump-rubber on the way, this time I noticed the A-arms on the left side weren't being held centrally on the bushes on the wishbone pivot, but were both as far back as they could go, the front one up against the face of the pivot and the rear one against the retaining washer. Annoying as I replaced A-arms and bushes a few years ago and they are the correct V8 ones. In theory this might have altered the suspension geometry, which could account for a very slight drift to the left on a flat surface, which implies a difference in castor angle between sides. But the direction the A-arms have moved is rearwards, which would have reduced the castor angle that side, which in theory should cause a drift to the right. So something else to investigate further. Used the alignment gauge again, the kit at my local tyre place should fit the V8 wheels OK as a double-check. But just like Bee it was immediately noticeable how much quieter and smoother the steering had become. After finally getting the wheels balanced correctly I was left with an occasional tremor over some surfaces, which I put down to the slight wear that I know exists in the rack, and the free-play in the column. On a 70 miles run there was absolutely nothing - excellent result.
Front Track Adjustment:
As well as describing measuring side-slip or scrub the Celica manual has a detailed description of how to measure the physical amount of toe. Basically you mark the middle of tread, in line with the centre of the axle, on the front or the back of the tyre, and measure the distance between the two marks, which is most easily done with two pointers on a connecting bar resting on the ground. Then roll the car half a revolution, so the marks on the tyres are now on the other side but back in line with the axle centre-line again, and again measure the distance between the two marks. If you carefully move your pointers from the first (reference) position to the second (comparison) position, and line up one pointer with its mark, you can directly measure the total toe between the other mark and its pointer. If you take the reference measurement at the back then roll the car forward to make the comparison, or vice-versa, so the marks aren't scrubbed off on the ground. If adjustment is required this method obviously needs you to move the gauge between the back and the front of the tyres several times, making small adjustments to the pointers each time, and being careful not to knock the pointers when moving from the reference side to the comparison side, in addition to rolling the car back and fore several times (which applies to both methods). The side-slip method will certainly be easier, but at a cost of typically £75 as opposed to perhaps nothing if you have a long enough broom-handle and some thin rod, considerably more expensive for something that may only be used once per year at most.
Having recently had a major clear-out of garage and shed I didn't really have the makings without butchering a garden tool or two, so for a few quid I bought some square tubing, threaded rod and nuts from B&Q. I measured the distance between the centre of the treads on each wheel, and this gave me the nominal spacing of the pointers. I also measured the ZS, which is quite a bit wider, and made the bar just long enough to take the pointers at this spacing, in case I ever needed to do that car as well. I drilled hole through the tubing (at the MGB spacing) to take the threaded rod, then overdrilled the bottom hole to allow a cap-nut to pass through which would be on the bottom of each rod. A butterfly nut further up the thread, above the tubing, clamps the rod in position. The rod rises vertically from the tubing and is then bent forwards to meet the mark on the tyre, it's overall length being such that the pointer touches the centre-line of the axle. I subsequently noticed that Moss have a similar gauge at about £50 so quite a bit cheaper than a Trakrite, but not as cheap as mine! However the instructions on the ordering page simply to measure between the outer sidewalls at the front of the tyre, then compare that with the backs. That would require the tyres to be perfectly mounted on the wheels, with no run-out. At the very least the car should be rolled back and fore half a turn so you are comparing the same point on the sidewalls, as I am doing with the centre of the tread.
Subsequently took the car to my local tyre place for a tracking check to find their stuff would not fit over/round the spinners, also my next local place. The fronts could be turned so that with the ears at an angle the laser unit fitted round them, but at the back it is a single central vertical bar and even the body of the spinner sticks out too far for that. Good job I got them (hopefully) close with my home-made gauge, looks like I have a 20 mile drive to the next nearest place with kit that should cope with them. One week later... Some nice weather at long last so a trip through the countryside to a place with screw-in adapters that hold the gizmos further out from the wheel hence clearing the spinner. Tracking is a shade under 2mm toe in, so given that the spec calls for 1.5 to 2.3mm I call that a result! Even more of a result is that checking is free, only adjustment costs!!
Front Crossmember November 2018
The mounting pads also changed for the later versions. Originally four AHH6205 for the uppers with a collar round the bolt hole projecting down into the crossmember, and four AHH6206 for the lowers which were flat. On rubber bumper cars the front lower pads were replaced with collared pads as there is now space for the collar to project up into the crossmember as well as the upper ones projecting down. The rears are unchanged. For that reason it would appear that all V8s would have lipped pads upper and lower at the front as they had the rubber bumper crossmember throughout, but this isn't shown in the Parts Catalogue or on suppliers websites. The Leyland Parts Catalogue for 1977 and later gives the amended quantities, but whether the change only dated from that point, or whether it was on all rubber bumpers and V8s and simply missed out of the earlier catalogue isn't known. Only Moss Europe (AHH6205SPKC for CB and AHH6205SPKR for RB) and British Parts Northwest (AHH6205/6P for CB and AHH6205/6LP for RB) seem to give a logically correct change point for the quantities with their poly kits.
According to Clausager V8 front hubs were fitted to 4-cylinder cars from the 1977 model year on. However this doesn't tie-up with front track information in the Workshop Manual and measurements on my V8. The manual states that from 1977 the rear track was 49.75" (1264mm) and the front 48.5" (1247mm), which was when Rostyles with less offset were fitted, i.e. 17mm narrower. But on my V8 with the same axle and apparently the same hubs the front track is 2mm more than the rear. More info on axles and track here, and on wheels and offsets here.
Stud wheel grease cap:
Centre-lock grease cap:
The stud thread is 1/4" UNF, so a nut welded onto the end of a tube or bar, with some means of levering it out once it is screwed in will do the trick. I thought about a couple of lengths of bar pivoted together, but I've got enough volume and weight of tools as it is. So I opted for a length of tubing about 4" long, with a nut welded to one end. A slot drilled in one side to insert the blade of a largish screwdriver, and away we go.
Screw the tube on to the stud until the slot is just about level with the end of the hub, insert screwdriver, and lever. If the slot is too deep in the hub the angle of the screwdriver will tend to try and push the cap to one side rather than levering it off, ditto if the slot isn't in far enough, close to a right-angle will be fine. The cap is pushed in about 3/4" or more so once the cap has started to move you will probably need to remove the screwdriver, screw the tube onto the stud a few more turns, then lever again. For replacement you can either leave the tube on the stud and tap the open end of the tube, or any one of a number of other methods. There is a distinct change in sound from a dull 'thock' to a sharp 'clink' when the cap is fully on.
November 2016: A fora contributor reports that his new grease caps were way too small, thinking they had to be hammered to expand into the hub (like the disc-type engine block core plugs). They don't - early ones may have been fairly loose fitting with a spring to retain them, but the Parts Catalogue and all those I've seen at suppliers and found via Google images are plain and are a light interference fit in the hub. Although my splined tubes have an ID of about 1.87", and grease caps have an OD of 1.845" to 1.85" (being simply pressed sheet they are not precision) the poster's splined tube was more like 2" ID i.e. non-standard. He's found some 50mm trailer grease caps, but they don't have the threaded stud on the end so even if he can get them in he may not get them out again! Neither do they have the flange, which means if he can get them down the splined tubes he stands a chance of getting them in the hub. It also begs the question of what the OD of his splined tube is, and hence the ID of the splined hub of the wheel. If they are standard then the walls of his splined tubes are significantly thinner than standard, with all that implies. If they are larger then he must have non-standard wheels as well.
Front Wheel Bearings
Front Bearing End-float
How do I set end-float?
Why end-float? Updated August 2011
The Factory Manual is quite clear on the need for a particular end-float i.e. 'free play' of 0.002" to 0.004" (2 to 4 thou) to be present with the type of roller bearings used in the MGB. Anyone who tells you to apply a pre-load of 11-15lb ft (i.e. the opposite of end-float) or whatever is wrong. That may be correct for other applications, but not for the MGB. Some say that you don't need shims in the front hubs, some even say you don't even need the spacer. Others say that the act of clamping the inner races, shims and spacer between the hub nut and the base of the axle spindle significantly increases its strength. I can certainly imagine that without shims or spacer the inner race could spin on the axle wrecking it, so personally I prefer to keep things as they came out of the factory.
As to why it's needed, consider the following: The brake disc gets very hot, that is attached to the hub, and when that gets hot it expands along the line of the stub-axle as well as radially, and this longitudinal expansion moves the outer running surfaces of the two bearings further apart. The stub axle should always be cooler than the hub, so won't expand as much, so the inner running surfaces of the two bearings aren't moved apart as much as the outers. If you look at a cross-section of the hub assembly you will see that the outer running surfaces are effectively between the inner running surfaces, and with the differential expansion each outer will be pushed closer to its inner, reducing the gap for the roller. With no running clearance when cold (let alone if there is 'pre-load'), despite the fact that tapered roller bearings are good at taking axial load as well as radial, this will squeeze the roller between the two running surfaces pushing grease out of the bearing and generating significant heat in the bearing itself, both of which will eventually result in premature failure of the bearing. With the correct end-float set when cold, differential expansion will be taken up by the end-float, so protecting the grease film and bearing surfaces.
How do I set end-float? Updated May 2015
It is advisable to have a selection of spare shims to hand before starting the job. There is a base 0.030" (BTB656) then for fine adjustment there are three sizes - .003" (ATB4240), .005" (ATB4241) and .010" (ATB4242). 50 to 55 thou total thickness seems to be the norm, and in the absence of a dial gauge additional shims will be required as below.
|You will see from this that as well as the base 0.030" shim you will need 4 of the 0.003", and 2 each of the 0.005" and 0.010" to make up any combination from 45 to 60 thou. There will almost certainly be some shims in the hub already, but if you make sure you have these as spares before you start you should be fine.|
July 2015: Front Bearing Replacement - by Michael Beswick (with additional comments)
Back home and on the ramp a quick spin of the wheel confirmed it was no better but no worse. The usual suspects all show a bearing kit (inner, outer bearing, oil seal) at about the same price as a single bearing. Being suspicious I wondered about quality. I bought both and was none the wiser- Timken and Toyo were the brand names in the B&G kit.
The car has wire wheels which means that most of the work is carried out down a 4" long tube.....
First off is to remove the brake caliper and tie it up out of the way. Next is removing the grease cap: mine has a threaded stud in the centre so I was able to use a 1 1/4 UNF bolt with a nut just on the end to screw on to the stud. (A second nut acted as a locknut). Out it pulled. Thankfully the split pin was put in a way to make it's unbending and removal easy (see later). Castellated nut size is 1 1/8 AF. Quick tap on the disc edge and the hub pulls free. On a stud-wheel hub the tabbed washer and outer bearing rollers will probably fall out at this point. Note the oil seal collar which will probably remain on the stub axle shaft. (Once when changing a hub I omitted this part-everything wobbled about a bit....)
On the wire-wheel hub the outer bearing rollers and tabbed washer are likely to be rolling about inside the hub "tube": the distance piece inside the hub. Levering the oil seal out allows the inner bearing rollers to be removed and then the distance piece. You now have the hub with only the two outer races (tapered collars) that the rollers run on. These need to be drifted out. There are convenient recesses (two at 180 degrees to each other for each race) that allow a long punch to be used against the larger back face of the races. Once these are out it is worth cleaning the whole internal "tube" out.
Inserting the new races is more difficult with a wire wheel hub because the outer race is down the 4" tube. A 1 5/16" socket fitted nicely on the (narrow) face of the race - an extension allowed it to be driven home - well nearly. The extension had the usual spring loaded ball bearing to ensure it remained in the socket. This allowed a certain amount of play which negated the "bang" of the hammer. It should be possible to compensate for this, but as I have a mate with an independent garage I went there. They had the correct tool which is very similar: a stepped disc in Aluminium with a central hole and a shaft with a shoulder that fitted in the hole in the disc. Then a big hammer and in it went. The race for the outer bearing is much easier as it is much more accessible, it would need a very large socket so I'd suggest a punch would do it fine - better still if it is ali (or brass, and I have used the old outer race to spread the 'point' load of the hammer round a significant portion of the edge of the new race, tapping alternately on opposite sides. Be absolutely sure you insert the outer races the correct way round i.e. wider face on the inside. Get this wrong and you probably won't be able to drift it out again as the recesses are not deep enough).
March 2019: It's important to get the races fully seated. The book says to do this by tightening the hub nut with no shims fitted, but there are a couple of ways to be sure. First is that there is a subtle change in tone when drifting the races in and they 'bottom', second is by inspecting the seats from the other side of the hub, looking for a shadow (not seated), and thirdly from the outside looking for the slightly reduced diameter of the hub at the top of the race.
As usually suggested I went for fitting the whole lot "dry" to get the end float correct. This requires the oil seal to be left off (advisable on wire-wheel hubs as otherwise the shims have to be repeatedly removed and replaced down the tube which is a pain). I fitted the inner race, distance piece and the 30 thou shim on to the shaft, and offered up the hub. However you need to be able to hold the hub horizontal with one hand whilst jiggling the outer bearing on to the shaft. A mole wrench clamped loosely (so adjustable) at the top of the disc to the back plate allowed two hands - actually fingers - to insert the bearing. Jiggle the tabbed washer on and tighten to 40 ft lbs + next slot in the castellation nut. It jammed solid..... (NB: when first fitting the hub with new bearings you leave out the shims and tighten to 40 ft lb to fully seat the outer races of both inner and outer bearings).
So remove nut, washer, and ease the hub off. The inner bearing, distance piece, shim remained on the shaft, so I added 21 thou - a guess (Brown & Gammons recommend a starting value of 50-55 i.e. the 30 plus 20-25) - of shims and repeated the operation. Bingo - just the right amount of 'tonk' as described by John Twist. (For those not familiar with the 'tonk' unit of end-float measurement see this setting procedure.) I have used a dial gauge but frankly it was more bother than it was worth.
Undo the lot and grease the bearings in the prescribed manner. I read a Moss Motors document but found I got as much in the hole for the shaft as I did in the race itself. A finger worked as well. Next fit the oil seal having first put in the distance piece. Then it all got a bit more difficult (with the wire-wheel hub, a stud-wheel hub is much easier). Without the oil seal and with the inner bearing on the shaft the shims could be added easily: once the oil seal is in place and the distance piece is flopping about in the "gap", the shims have to be added after the hub has been fitted to the axle shaft (i.e. down the 4" tube), hence the need for the mole wrench to keep it square. I tried all manner of ways to trickle the shims on to the shaft but they get caught on the threads or the shoulder. Eventually I decided to use grease as stiction and fit them to the bearing. I was able to use my finger to line up the bearing square on the and of the shaft and tickle it in. Fitted the tabbed washer and nut....and it jammed solid.
By now there was grease in the system and I had fitted the oil seal so I just kept going (4 attempts) till I got it right. On my axle shaft there was only a single hole for the split pin - not a second at right angles, so I had to use the top end of the torque range to get it to line up. When inserting the split pin do so in a way that the longer leg is facing towards you, and then PULL it a little towards you. It is much easier to push it straight for later removal than trying to get a hook round the back!
So how would I do it next time? Broadly the same: theoretically grease should not compromise the end float, so I am blaming fitter error. However once the oil seal has been fitted trapping the distance piece, fitting shims becomes much more difficult, so I would still use the stiction method-after all grease in there by then.
Front Bump/rebound rubbers Added September 2010
When fitting the new bracket and spacer get the long bolts up through the bottom part, the spacer and the cross-member first, and fit the spring washers and nuts. Partially tighten those, and only then tap the bracket with a hammer and/or use a pointed drift to line up the top holes for the short bolts, fit them and their spring-washers and nuts, then fully tighten everything. Daub new spacer and bolts, and the inside of the rubbers bracket, in Waxoyl before fitting!
Front Spring Replacement
The first thing to say is that spring compressors are not required. Support the front of the car safely e.g. with axle stands under the chassis rails and/or front crossmember. Place a jack under the spring-pan and raise the axle until the upper damper arms are just clear of both the rebound rubbers.
Most seem to agree thus far, but opinions differ as to whether the four bolts that secure the spring-pan to the lower A-arms should be removed next and just the spring-pan lowered to free the spring, or whether the lower trunnion bolt should be removed disconnecting the A-arms from the swivel axle, and the A-arms and spring pan complete lowered to free the spring.
Having tried both ways I would only ever recommend the latter method, for the following reasons:
Secondly, it is my experience that the tapered ARB drop-link pin (all bar 74 to 76 RB roadsters) seizes in the spring-pan, and the two have to be removed together for them to be parted on the bench. If this happens you have no option but to use my preferred method.
Removing the lower fulcrum pivot bolt (through the swivel axle trunnion and outer end of the A-arms) is a single operation and allows you to lower the spring pan on the jack while it is still held securely, until all spring tension is released. With the jack out of the way you push the pan down a bit more with one hand and simply lift the spring out with the other. That done, you can tackle the spring-pan to A-arm bolts in complete safety.
This method also allows you to inspect the thrust-washers on the pivot bolt, and reverse or replace them if grooved which can silence clonks when applying the brakes.
Another more recent option has been to remove just two of the spring-pan bolts, and slacken the other two, then allow the spring pan top pivot down on the A-arms. But the A-arms are not parallel so the pan is going to bind between the arms unless the slackened bolts are very slack. This will almost certainly have to be the inner bolts given that the ARB drop-link pin seizes in the spring-pan. Also if removing the spring is anything to do with working on the A-arms, replacing the inner bushes, or any of the pivot pin components, the pivot pin will have to be removed anyway so you might as well do it up front. With the rear two bolts through the spring-pan and A-arm removed, and where fitted the drop-link detached from the ARB, both A-arms can be removed, the front one complete with spring-pan and drop-link.
I did use this method to reassemble with new CB roadster springs which have a long free height and I couldn't push the A-arms down far enough to insert the spring. But then I had to move the jack from the middle of the spring-pan to the very outer edge before I could compress the new spring enough to get the fulcrum bolt fitted. Leaving the A-arm to spring-pan bolts slack also helps with refitting the pivot bolt through the arms and the trunnion, if the holes are offset you can't get the bolt through the second A-arm hole. If none of the spring-pan bolts have been loosened the ends of the A-arms should still be in line.
Some have said that just letting the suspension hang down on the rebound rubbers takes enough tension out of the spring to be able to remove the pivot bolt or the spring-pan bolts safely, which could be the case with the shorter and harder front springs, but until you have done it once you won't know, and you don't want to find out the painful way that it isn't the case!
In the time-honoured phrase - "reassembly is the reverse of removal" - that is, push down the A-arms complete with spring-pan, insert spring, jack spring-pan and pivot swivel-axle until the lower bolt can be inserted. The only thing to watch is that the grease seal, thrust washer and seal support are all present and correct on reassembly.
Another tip when buying new springs of any type is to insist on a pair with the same free height! The pair my supplier put on the counter for Vee differed by nearly 1/4". He got a matched pair without quibble, but said "it won't make any difference". At first I thought he meant that the free height made no difference to the loaded height which is obviously wrong, but once fitted although the loaded height had been the same with the old springs with the new, even after a shakedown run, there was a 1/2" difference. So maybe he meant "it doesn't matter what the free height is, the loaded heights will probably be different anyway!". Also the free heights were quite a bit higher than spec, so if you are able go for the shortest.
Update September 2007 Another tip is that when sliding the A-arms down off the trunnion, as soon as the hole in the trunnion is cleared refit the bolt and nut and this will stop the grease seals etc. falling off and the bolt/nut getting dirty/lost. But I digress. Many moons ago for various reasons I fitted CB GT front springs to the roadster as they are stiffer, but with a lower free height, which gives much the same ride height. At the time they gave much the same ride height with less roll and dive under braking, but since then they have settled and for some time I haven't been able to get the hydraulic jack under the rear edge of the cross-member, and the A-arms and track-rods were both angled upwards (outer ends relative to inner) which didn't seem to me to be correct. So I decided to replace them with new originals, and in doing so found that I needed to employ a combination of the two methods above. The CB GT springs have a free height of 9.32" (and the used ones were a little less than this anyway) and pushing down on the A-arms/spring pan with the lower fulcrum pin removed was all I needed to do to get the old spring out. However the correct springs have a free height of 10.2" (and in fact the new ones were a little taller than that) and I could not push the arms down far enough to get the new spring located in the groove in the spring pan. So I removed the inner spring pan bolts altogether, and with the outer bolts slackened (actually only the bolt as I couldn't get at the anti-roll bar drop-link nut easily) the pan pivoted downwards with a bit of pressure and in went the spring. I then jacked up under the inner edge of the pan, and with a bit more levering got the holes aligned and the bolts back in. This is still a much safer method than complete removal of the four spring pan bolts as the pan and hence the spring is still securely retained by the outer two bolts (or bolt and anti-roll bar drop-link pin). So far so good, but when I jacked up under the spring pan I found I couldn't compress the new springs enough to get the holes in the fulcrum and A-arms aligned, I had to jack under the far outer edge of the pan to be able to do it. Not only that, but when on the ground a quick measurement showed that the front ride height had leapt up from 14" to 16" and looked ridiculous!
Not being a believer in springs 'settling' soon after installation, nevertheless a tour round some of the speed-hump ridden streets of Solihull and some bumpy country lanes for an hour settled them to 15.375" at the front both sides, with 14.125" at the rear also both sides. Better, but still a little high at the front, but it will probably settle more over time. I think the initial settling is due to the front springs only sitting in the spring-pan and cross-member, and so not fully seated until they have been worked up and down a bit. In contrast the rear springs are positively located by bolts and I'd expect very little initial settling. The A-arms and track rods are now angled slightly downwards (click thumbnail), and I now have 6.625" clearance under the front cross-member as opposed to about 5.5" previously.
Update October 2007
Update October 2009
Measured Bee's ride height as 14.75" right front, 14.625" left front, and 14.25" for both rears. Vee's are 14.5" right front, 14.625" left front, 15.375" right rear, and 15.6875" left rear.
I've been becoming increasingly aware of a clonk when applying and releasing the brakes in Vee, even gently, and feeling something through the pedal, although nothing came up on the MOT. Getting the spring pans up on axle stands i.e. wheels off the ground I couldn't find anything loose on the steering arms, track-rod ends, calipers, dampers, A-arms, wheel bearings, trunnions or king-pin bushes except that when I levered the tyre up and down the swivel axle was moving up and down on the king-pin, approaching a millimetre, and accompanied by a clonk. "Ah-ha", I thought, "King-pin thrust washers and shims". However I couldn't and still can't see how this would occur under braking - the weight of the car is already on the thrust washers, braking is only going to add to that, and braking is putting a rotational force on the king-pin bushes and not vertical (subsequently found to be worn lower trunnion thrust washers, on B as well). Nevertheless as the Workshop Manual quotes
.008" to .013" (.20 to .32mm) corrected February 2018 following comments from Gary Roberts 0.002" (0.05 mm) they need attention. The Leyland Workshop Manual is a little confusing as it refers to 'swivel axle end-play of 0.02 in.' in section K4, and 'swivel pin end-float between 0.08 and 0.013 in.' in section K6. However whilst both K4 and K6 refer to Assembling and Replacing, K6 is referring to the lower pivot/fulcrum. So rather than para 2 of K6 referring to 'swivel pin end-float ...', ideally it would refer to lower fulcrum/pivot pin end-float. Appropriate corrections in the vertical free play of swivel hub on swivel pin have been made below.
The Workshop Manual shows three washers but only labels two of them - a thrust washer and a floating thrust washer (shim) .052" to .057" i.e. .055" nominal. The Parts Catalogue also shows three washers, but just as part of a king-pin repair kit and not as separately identified parts. The MGOC site shows the main thrust washer ATC4264 but not the shims, saying the shims are only available as part of a repair kit that includes the king-pin. Googling ATC4264 displayed Quinton-Hazell, Brown & Gammons, MGOC and Moss Europe hits. B&G didn't list any other parts, QH listed shims with the main thrust washer but didn't say what axle it was for, MGOC listed the shims as separately available although only for the MGC, but Moss listed the shims indicating they are suitable for both the B and C! The shims are in three different sizes ATC4261 (.052" to .057" i.e. .055" nominal), ATC4262 (.060" nominal) and ATC4263 (.065" nominal) which are selected to obtain the required end-float, the main phosphor bronze thrust washer being sandwiched between two of the shims. But with 0.005" tolerance in each of the three sizes, one could go though an awful lot of them to get the required 0.002" maximum end-play. So off goes my order to Moss for two sets of washers and shims, as well as the bump/rebound stop which I had noticed had lost its bump rubber on the left-hand side. While placing the order online I noticed a checkbox by each item something to do with back-ordering. It was only afterwards I wondered if some or all of the items were out of stock, which is a possibility for things like the shims, much less so for the bump/rebound stop, I would have thought. But in the event they all arrived two days later.
So up goes the front of the car (cross-member on axle stands) and off comes the right-hand wheel. It seems to me that just undoing the big nut on the end of the king-pin will allow the trunnion to come off and reveal the thrust washers and shims, the pin through the trunnion and damper arms is obviously clear of it. However the rubber bushes around that pin fit into a notch in the king-pin, so really the damper arms need to be disconnected from the trunnion and the bushes removed before the trunnion can be removed from the king-pin. And when doing that you will probably need to slacken the clamping bolt that goes through the damper arms. Jack under the spring-pan so the damper arms just lift off the rebound rubbers to take the tension off the trunnion, damper arms and pin before trying to remove the pin. Having replaced dampers and a swivel axle at various times, if I hadn't had that pin and the bushes out beforehand they were seized solid and I had to cut through the pin both sides before I could part them, removing the damper arms clamp bolt and wedging the arms apart meant you can do this without damaging either arms or trunnion. So if you haven't had yours apart before you might like to lay in a repair kit or two (bushes, pin and nut) beforehand.
Both top link repair kits I have purchased in the past have been supplied with a Nyloc nut instead of the original castellated nut and split-pin, even though the pin does have the split pin hole. These nuts have been way too deep, so much so that the threads of the pin weren't engaging with the nylon insert and so totally inadequate. If you use a Nyloc at least three threads of the pin are supposed to be exposed, but I wouldn't even trust that as this one pin is all that is holding the top of the wheel up. Fortunately I had suitable castellated nuts I could use instead, and split-pins. At the time of writing MGOC (item 73) say they are supplying Nylocs with this kit, and Leacy say (and show) they supply castellated, so guess which one gets my order.
Even then the trunnion could be stuck on the king-pin, so with the nut on the king-pin slackened clear of the top of the trunnion but short of the top of the king-pin, lower the jack from under the spring-pan, and tap the end of the king-pin. Mine are rounded at the top so there was no chance of damaging the ends of the threads, and it came free. Before completely removing the nut jack under the spring-pan again to stop the king-pin and trunnion flying apart. Also have a length of cord available so that when it does come off you can tie up the hub e.g. to the bump/rebound bracket or anti-roll bar drop link to stop it hanging on the brake hose.
With the trunnion lifted off the end of the king-pin you can retrieve the thick phosphor bronze thrust washer sandwiched between two thinner steel shims. It's now a case of juggling shims, refitting the trunnion and retightening the king-pin nut and checking play. If you have a castellated nut it makes sense here to drop a spacer over the king-pin before fitting the nut so you only have to tighten it a few turns, instead of winding it on and off an inch or more. It's even more important with a Nyloc nut, or you will have to replace that as well, with the number of times you are likely to have to fit and remove it wearing the nylon insert out. If you can't find a spacer that keeps the nylon insert clear of the threads when the nut is tightened, try and find a plain nut instead. To check end-float with each combination as well as fitting the trunnion to the king-pin I slotted the pin back through the trunnion and the damper arms and fitted the nut a few turns (the damper arms with trunnion can be lifted up far enough to clear the top of the kin-pin), lowered the jack under the spring-pan so the tension of the spring was pulling the trunnion down, then lifting and lowering the hub and swivel axle reveals the play. Remember to jack under the spring pan again each time before removing the king-pin nut to try another combination.
And this is where the problems started. The Moss shims came in three bags, two to a bag, with the bags labelled with the three different sizes. The shims were all stamped with a sizing number, and I had two each of three numbers 6 (or 9), 7 and 8 - all so far so good. But when I started juggling shims it wasn't making any difference, which didn't make sense. So I started measuring everything - new washer and shims as well as the old (the old shims had no visible markings) and discovered that my six new shims which were supposed to be two each of three different sizes, were actually five thin shims and one thick! Added to that the new thrust washers were actually thinner than the old ones, at 0.179" as opposed to 0.184", and the old shims were 0.054" and 0.064" i.e. one thin and one thick, and apparently unworn! I suppose the thin one could originally have been a thick or middle one, worn down to exactly the thickness of a thin one, but I find that unlikely. Also I suppose it could have been the top of the swivel axle or the bottom of the trunnion, that bear on the shims, that had worn instead. I tried various combinations, including the new thinner thrust washer plus three thin shims (too thick), but the only combination that came anywhere near was my one new thick shim in place of the original thin shim, i.e. the original (thicker) thrust washer plus two thick shims. This left it with no detectable end-float at all, but the steering did turn freely, and a test-drive did show it self-centres even at the lowest speeds, so in theory is a possibility (but shouldn't be used as some end-float must be present and the suspension unloaded to allow grease to get through the upper trunnion). It's difficult to measure the end-float without a dial gauge, and about the only thing you can do is use a 0.0015" feeler gauge (the thinnest in my set) to check it goes in and leaves virtually no further movement of swivel axle on swivel pin, to get the required 0.002" maximum. As mentioned above with 0.005" tolerance in each thrust washer it's not easy to get the maximum 0.002". The only other combination with the washers I had gave a lot more than a quarter of a millimetre as judged by eye. So a phone call to Moss, who say send them back. Fair enough, but simply picking others out of the same bins isn't necessarily going to be any better. They said they would measure the replacements (really!?) and make sure I got two of each, we shall see. In the event I kept two of the thin ones and the one thick one, just returning three thin ones, hoping to get two medium and a thick back. In the event about a week later I get the correct ones, plus an automatic refund of my return postage, which is pretty good. I swapped one of the thicks for a medium on this first side, but when juggling the other side found only the original combination (a thick and a medium) gave any end-float, so I ended up leaving those in.
When you have found the right combination remove the king-pin nut for the last time (and its spacer if used), lift off the trunnion and grease the thrust washer and shims by applying grease directly to them at this stage, not from the grease nipple. Refit the trunnion and king-pin nut (but don't tighten it yet), and insert the trunnion bushes into the trunnion. Lubricate the bushes with a suitable lubricant e.g. Waxoyl to make fitting easier. The bushes have to be wedged into the trunnion before you will get them in between the damper arms, even if the damper arms are wedged apart with an old screwdriver between the bosses of the cross-bolt. Use a plain nut and bolt and large washers of a suitable size through the bushes and the trunnion, to squeeze the bushes in to the trunnion. Even so they are unlikely to push straight in between the arms of the damper, I had to turn the trunnion a bit to get one bush started, then a paint-scraper as a sort of ramp to squeeze the other one in while I pushed on the trunnion. Again Waxoyl on the faces of the bushes (and inside the steel sleeves to prevent rusting to the pin in future) and the damper arms makes this easier.
Make sure you get the trunnion the right way round, the vertical king-pin is INBOARD of the horizontal trunnion pin, not the other way round as is shown in the Workshop Manual and Parts Catalogue exploded drawings!! However the assembled drawing in the Leyland manual is correct, as are both drawings in Haynes. This MGOC catalogue exploded drawing is also incorrect, but the photos of the assembled units are correct. The Moss exploded drawing is also correct.
Peer though the damper arm, tapping it up or down and the trunnion in or out to get the holes aligned on the side the pin is inserted from, then insert the pin, again lubricating it e.g. with Waxoyl. The pin goes in from the front on the right-hand side so the cut-away on the special head engages with the raised portion on the damper arm (from the rear on the left as the dampers are not handed). Once the main body of the pin has started going through the first bush in the trunnion, peer in from the other side and tap and align that as well, until you can tap the pin all the way through. Fit the nut tightening to 40 ft lb, and the split-pin. Tighten the damper wishbone cross-bolt (wedge removed) to 28 ft lb.
With the top link assembled you can finally tighten the king-pin nut to 60 ft lb. Leaving it loose until now allows the trunnion to take up the correct position and be twisted on the king-pin so the holes in the damper arms will line up with the holes in the bushes. Grease the king-pin as normal i.e. from all three nipples using a grease gun until clean grease oozes out of the joints, and wipe off the excess.
And the result? Just the pigging same! However when pushing the car back and fore to work it across the garage to give me more room for the second side I could hear a clonk as I started turning the tyre on the floor. Getting the Navigator to keep doing that while I looked and felt underneath showed no relative movement between track-rod end and steering arm, or up and down or back and fore movement of the track-rod, but I could definitely feel the clonk in them more than in anything else anywhere round the suspension or rack. Wheel off and there is some very slight up and down free-play in the body of the track-rod end relative to the steering arm, and with them parted the pin is flopping about all over the place, so it looks like new track-rod ends for Vee as well.
Lubrication March 2014
As far as routine maintenance goes it's just a matter of unloading the suspension - supporting the body safely with the wheels hanging down - so that grease can work its way round all the bearing surfaces. If it's loaded then it isn't going to get to the surfaces that are passing the weight of the car through to the wheels. You can also work the steering from lock to lock after the initial lubrication, then add a bit more. I always remove the wheels as it gives better access from the sides. Wipe the ends of the grease nipples to avoid pumping dirt in. The fitting on the end of my grease-gun needs to be dead in line with the nipple, or grease escapes rather than going in. Pump till it comes out from under the upper trunnion, and from past the seals each end of the lower trunnion, and wipe off the excess.
Originally there were only two nipples per side - one at the top of the swivel axle and one at the bottom of the king-pin. But this led to inadequate lubrication at the bottom of the swivel axle so a third nipple was added here. On the right-hand side both swivel axle nipples point forwards, but on the left the lower one points backwards for some unfathomable reason. The one in the kingpin screws upwards, and should be an angled nipple (UHN 445) to make connecting a grease-gun easier if the car is on axle stands. It's a bit hit and miss as to where this points, and if not ideal you can slacken it a little to get the gun on without loosing too much grease from the threads, retightening it afterwards.
Between the upper and lower king-pin bushes there are two 'dust excluder' tubes, a spring and two seals. The tubes fit inside each other and the spring keeps them and the seals pressed against the upper and lower parts of the swivel axle to retain the grease (more than keeping dust out) which surrounds the king-pin. If you find grease oozing out below the upper bush or above the lower then this 'retainer' has failed in some way. As long as grease comes out above the upper bush and below the lower then lubrication is fine, just wipe this 'excess' off, unless more is coming out there than the bushes!
Both the swivel axle nipples are straight, but they should be of different lengths. Although they are usually shown as the same size in the drawings a short one (UHN 400) goes in the top and a long one (549229) goes in the lower position. This is because immediately above the lower one the casting bulges out, which means that you can't remove or tighten it with a socket, you have to use a small open-ended spanner. The long nipple has the hex outboard, so can be removed and tightened with a socket. The upper nipple is on a flat surface so a short one can be accessed with a socket. Update March 2019: It occurred to me that the bulge may only be on the front, so checked both sides on Vee (who was more accessible) and sure enough a socket fits the lower rear-facing one on the near-side easily. So check the off-side ... and the same socket fits that just as easily! All I can think is that the incorrect nipple on Bee had a larger hex which was why it needed a spanner. End of Update
For some reason Bee had three angled nipples on the right-hand side, which made it awkward to get a grease gun on even on full lock, and as I say above unless it is dead in line grease leaks out from the fitting on the end of the gun. After many years cussing this, I finally got round to getting the proper nipples. Because of the bulge in the casting I couldn't even unscrew the lower angled nipple. But they are usually in two parts, with a short straight piece screwed into an angled piece. So I had to remove the outer part before I could unscrew the body. With two straights, greasing that side now is a doddle.
August 2018: I've seen mention that angled nipples (UHN445) on the bottom foul something when trying to screw them in. 'A pan' was mentioned but I think they must mean the disc backplate as the A-arms and especially the spring pan are miles away. Even so mine clears the backplate, so theirs must have a longer angled section than mine. The two-part angled as above wouldn't have the problem if fitted in two stages. Depending on how the two threads start the nipple might tighten facing the backplate, or something else that prevents you getting a grease gun on. In which case partially unscrew it to suit, then tighten it again afterwards. You shouldn't get much grease escaping just a quarter-turn slackened.
Update August 2010:A tip when disconnecting the track-rod ends from the steering arms. The nut is usually a Nyloc, and the effect of this is that once the taper is broken you can't turn the nut on the thread without locking the taper again, as the stud just turns in the ball-joint. And if using a screw-type splitter you really need to have a nut on several threads if you are to avoid damaging the end of the stud. The tip is to remove the Nyloc nut, then put a plain nut on until the end of the stud is close to the face of the nut, before using the splitter. As long as the threads are good the plain nut will be much easier to remove once the taper is broken. For replacement the same problem occurs, so screw the plain nut up tight to lock the taper, then replace with the Nyloc nut.
But I digress. Make alignment marks on the tie rod and track rod end. Slacken the lock-nut and count how many turns are needed to separate the track rod end from the tie rod. Change the gaiters then screw the tie rod and track rod end back together the same number of turns it took to part them, finishing with marks aligned, assembling with copper grease to aid future removal/adjustment. Fasten the tie or clamp on the smaller end of the gaiter, but not so tight that the tie rod can't be turned without twisting up the gaiter during future tracking adjustment. If changing both gaiters fasten the tie on one big end but leave the other off for the moment and use an oil gun to inject 1/3rd pt (0.4 US pt, 0.2 litre) of the same oil as is used in the rear axle i.e. EP 80W/90 GL-5 or equivalent into the big end. Hold the bottom of the gaiter up against the rack housing while you inject the oil using a small oil gun in the top, periodically moving the rack slowly from lock to lock to distribute the oil.
Update Autumn 2005: If you put your hand over the top of the big end of the gaiter with the thumb down one side and forefinger down the other you should be able to squeeze and stretch the gaiter such that the bottom half is stretched into the groove of the rack to make a reasonable seal while you are injecting oil, and stretch the top half so that you make a small loop, or at least an area of lessened tension, to allow you to insert the nozzle of the oil gun. However if the shape or size or your oil gun prevents its insertion you could try this tip sent to me by Michael Beswick: "I found a 8" piece of windscreen washer tube, cut one end at a shallow angle to make a bit of a point. The other end I put in boiling water before forcing it over the pointy end of a biro. I left it for a while and the result was a small funnel shape that the nose of my oil can fitted into neatly. I released the clip on the gaiter, put the tube in at the top of the gaiter and managed to get it all over the metal fitting. Tightened the clip to just nip the whole assembly. Inserted oil can in the funnel end of the tube (it was quite soft so the oil can spout fitted reasonably tightly) and hey presto! A little care is needed or the tube blows off the spout. Remove oil can and carefully pull out the tube (which can be kept in the right plane)." Finally, fasten the remaining big end tie or clamp.
You should be spot-on, but unless you know your tracking was right before there is no harm in getting it checked, and you know you will be able to slacken and adjust everything before it all seizes up again.
Rear Bump Rubbers, Pedestals and U-bolts January 2011
Pedestals and U-bolts
Bump Rubbers: AHH9158 for all cars. Just seen a top tip on the MG Enthusiasts BBS from Fletcher Milmore on how to fit new Bump Rubbers, which really appeals to my love of lateral ideas. The hole in the rubber is quite a bit smaller than the peg they are supposed to fit over and people often complain what a chore it is. Fletcher's method is:
Pedestals and U-bolts: October 2016
The pedestal situation is a little confused. The Leyland Parts Catalogue lists nothing for the banjo axle, AHH7335 for tube axle 4-cylinder cars and RB V8s, and BHH1030 for CB V8s (although suppliers indicate this is NLA). Moss Europe and Brown & Gammons to name but two say AHH6053 for banjo and AHH7335 for all tube-type i.e. both 4-cylinder and V8, CB and RB. The CB V8 item in the Leyland catalogue is drawn taller, but as there was only one bump rubber for all cars it seems odd that the CB V8 would have used a taller pedestal than anything else. One V8 Register post says "so for your C/B car you will need the shorter pedestal" but when you look at AHH7335 you couldn't get anything shorter. Only one bump-rubber (AHH 9158) is listed in the various sources for all cars. The Leyland Parts Catalogue specifies U-bolt AHH6452 for the banjo axle. For the tube/Salisbury axle it specifies AHC109, changing to AHH7333 at roadster No. 386795, however the suppliers specify AHC109 for all tube axles.
The only thing you can say for sure is that both types are specifically shaped to fit the axle casing - tapered in the case of the banjo axle and parallel in the case of the tube-type/Salisbury axle.
These rot over time, and collapse if your suspension is anything like mine and bottoms over bumps when touring fully laden. If they crumble away altogether you may find the lever-arm damper ends-up limiting axle travel, which won't do it any good at all. I could see one of Bee's had holes and become partially crushed, so ordered a pair (AHH7335 at about a fiver each so not expensive) the next time I was ordering some other stuff. Before starting check the rebound straps also need to be in good condition, and get some in if they are in poor condition. However they have their own issues!
Support the rear of the car securely on axle stands by the rear spring front hangers, so the axle can hang down and give you more working space above. Take the road wheel off.
Jack under the spring to raise it an inch or so. Undo the U-bolt nuts working round all four bit by bit, rather than fully removing each in turn. With the spring supported and raised a bit you should be able to pull the damper plate down off the U-bolts and push it out of the way, also remove the bottom spring retaining plate below the rubber pad (which can remain in place if sound). The U-bolts may need to be tapped up a little to get the two plates off. Check the pads and replace if required.
Tap the bottom of the U-bolts gently bit by bit up to the bottom of the upper spring retaining plate, and wiggle the bolts complete with pedestal out of the plate and off the axle.
With the pedestal upright swivel the U-bolts through 90 degrees i.e. horizontally instead of vertically as fitted so a straight part is under the pedestal pad, then you should be able to pull them all the way out. If the pedestal has collapsed you may need to exert some force to remove the U-bolts from it by levering the pedestal pad away from the curved section that goes round the axle. If the U-bolts show any thinning from corrosion they should be replaced as well.
Protect the new pedestal as required. Feed the U-bolts in sideways under the pedestal pad - with chrome bumper pedestals you may well need to lever the pad away from the curved part even on new pedestals to get the end of the U-bolt past the pad without damaging the threads - then turn to point downwards.
Fit the assembly onto the axle from above. You may find you have to 'spring' the ends of the U-bolts in a little to get them through the upper spring plate. If you can get one end through, put a nut on a couple of threads to retain it while you are pressing the other end in. Without this you may find that as the second end goes in the first pops out again.
With all four ends in, tap downwards past the spring so the pedestal is sitting on top of the axle.
Fit the lower spring locating plate over the end of the U-bolts, again putting a nut on a couple of threads to retain one end while pressing the other end in. The damper plate should fit straight on.
Fit and tighten all four nuts bit by bit working round each in turn once they start to compress the rubber, checking the pedestal is level on the axle i.e. has equal clearance from its lower edge to the guides on the axle. There is no torque for these nuts as typically they will be Nylocs, so you will just have to use your skill and experience to know when to stop. With new rubber pads you may well have to retighten two or three times as they settle. If you find you have rear-end steering as you accelerate and decelerate, then they are loose. Also if you see orange staining where the axle butts up against the upper spring locating plate they are loose.
It is purely the leaf springs that locate the rear axle in the car, nothing else. Just in case you wondered how much it moves around under acceleration and cornering forces, have a look at this Healey video which has much the same leaf spring and lever arm damper arrangement: https://www.youtube.com/watch?v=tN-4LLAKlpw. Note that the movement is nothing to do with the lever-arm dampers, telescopics would make little if any difference. You would need a multi-link system to positively locate it against rotation about the half-shafts and sideways movement.
Leaf Spring Lubrication Once I started using the V8 in mainly dry weather the rear springs started squeaking quite badly, which had the Navigator complaining. I didn't want to spray oil on them as I was concerned for the rubber bushes at each end, particularly the front bush which is a lot more difficult to change than the rear bushes, so decided to use Waxoyl which doesn't harm rubber. Waxoyl is also much less likely to get washed out from between the springs when Vee does get wet, like on organised runs!
I actually painted it on semi-congealed rather than as a liquid suitable for spraying, then used a hot air gun to melt it whereupon most of it was absorbed into the gaps between leaves and interleaving and little dripped off. At first it didn't seem to have made much difference, but then over a bit of driving it seems to have 'worked in' and they have definitely become much quieter and now I can't say that I notice them at all and neither has the Navigator commented recently. It would have been much easier to apply with the springs removed from the car and laying on their sides, but a much bigger job overall of course.
In response to a question on a Bulletin Board I mentioned this but another contributor said he didn't like Waxoyl because it dried out. In my experience whilst it does 'dry' in that the white spirit that makes it liquid evaporates it leaves behind the waxy stuff which if you rub it between your finger tips is still slippery i.e. does still lubricate, and as I say is much less likely to get washed out than oil or even grease. And being drier it will pick up less dirt and grit.
Update August 2007: Having broken a rear spring on this year's Snowdon Run before I replaced them I laid the new springs on their sides, painted on some dollops of Waxoyl, then used a heat gun to melt it into the crevices between springs and interleaving. When they were 'dry' I could pick them up by the eyes and it was a cleaner job than I was expecting to fit them while coated. Incidentally, this is the third set of springs I have bought from three separate suppliers and fitted to two different cars - one chrome one rubber, including stiffer rubber bumper roadster springs to the chrome bumper roadster, and I have never had any trouble getting the shackles, damper drop-links or rebound rubbers attached, or in getting the shackles to point downwards. The weight of the body was more than enough to compress the springs before the body lifted off the axle stands in all cases.
Rear spring mounting June 2016It's well known that rubber bumper cars higher ride height is obtained by a modified crossmember at the front and lowered spring mounting points at the rear, and this applies to both 4-cylinder cars and V8s. Also that the V8 chrome bumper was the first to use the modified crossmember as it needed more ground clearance for the exhaust than the 4-cylinder. But what about the rear springs on chrome bumper V8s? Over the years I've seen arguments as to whether the rear mounting points on these cars were lowered or not, and I've been intrigued as to the answer. At a recent MG run I had the opportunity to find out as there were not one but two chrome bumper V8s. When parked up at the finish I happened to see the cars, no owners in attendance to ask, so I took some surreptitious pictures.
The results were quite interesting: Both 4-cylinder and V8 rubber bumper cars have lowered front and rear mounting points consisting of a deeper front bracket and the holes for the rear shackle pins being below the centre-line of the chassis rail, but the chrome bumper V8 only has deeper front brackets, the rear points are through the chassis rail just like the 4-cylinder car. Even so the front brackets are different between chrome and rubber bumper V8 - the rubber bumper part looks deeper than the chrome bumper, and has a reinforcing piece. Whilst British Motor Heritage lists rear spring front hangers, it only differentiates between chrome bumper and rubber bumper, V8 is not mentioned, ditto Brown & Gammons and Moss Europe which quote the BMH part numbers.
Rear spring replacement November 2010: June 2016: I've just become aware of a news item posted in 2015 on the West Cheshire MG Club website (scroll to the bottom) saying that BMH guarantees correctly specced springs made by GB Springs. However I can find no reference to them on the BMH website. But GB Springs on their website do list what looks like the full range for the MGB at least, plus for other models and marques.
On fitting the new springs one point that did differ on the rubber bumper V8 compared to the CB roadster (both CB roadster and RB roadster springs on this car) is that on the V8 I only had to lift the springs up by hand and I could insert the shackles. On the roadster I can remember the new springs being too short, and had to jack under the spring to slide the rear eye back along the chassis rail until I could get the shackle inserted. One problem I had with the V8 that I hadn't had with the roadster with either new red poly bushes at one time and new rubber another, is that the latest bushes have a significantly thicker flange than before, which meant that even without the lock-washers I couldn't get the nuts started. I had to squeeze the sides of the shackle together with a small sash cramp to compress the bushes before I could get the washers on and the nuts started. Other than that everything was straightforward, the only complication on the V8 being the Hopkinson anti-roll bar. To get the bracket of this located on the U-bolts I had to jack under the spring until the bracket was just below the end of the U-bolts, then slowly lower it whilst locating the bracket holes over the threaded ends, until enough thread was sticking through to get the nuts started. Both the front eye bolts and the shackle nuts are done up until they suddenly come tight as the front hanger butts up against the bush sleeve, and the shackle pins have shoulders which the closing plate clamps down onto. How tight to do the U-bolt nuts is always an awkward question - I've never seen a torque figure given, so how tight do you go? Having done this job several times now it seems to me that as you start to compress the flat rubber bushes either side of the spring the nuts get stiffer quite gradually, then they seem to get quite a bit stiffer quite quickly. This is about the point I stop, but they need checking again after a short shakedown drive, and again several hundred miles later (checking the front eye bolt and the shackle nuts as well this time). During my shakedown drive I noticed some creaking coming from the right-hand side, on my return I could tighten this side quite a bit more (possibly as I did that side a couple of days prior to the left-hand side) and on a second run the creaking had disappeared. One thing that did not change was the rear ride-height.
One thing I did which I usually do when re-fitting MGB components, to ensure easy removal in the future, is to coat the front bolt and bush and the rear shackle pins and bushes and the rear chassis holes with Waxoyl. Before fitting I had also laid the springs down on one side, painted a decent layer of Waxoyl on, then ran my heat-gun up and down to completely melt it into the joints between springs and interleaving. When that had solidified I turned them over and treated the other side. Not even that messy when picking them up to fit to the car, and that is what latex gloves are for.
So I have now bought three different types of spring, from three different suppliers, over a period of years, and fitted them to two different cars, and never had the 'too-hard/arched' problem that so many complain about. Am I just lucky? Or is everyone that gets this problem buying from dodgy suppliers? Or are they simply not installing them correctly? I wish I knew.
July 2010: A pal's MGB fails its MOT with a broken rear spring.
For security I drove the front of the car up onto ramps, with the front of the car pointing down the slight slope on my drive. The rear was supported on axle stands just in front of the front eye, with pieces of wood inserted into the flanges of the bracket between the floor reinforcement section an the axle stand. If one end is on its wheels and you are pulling an pushing at things it's very easy to tip stands over, particularly if its the front on the ground and the rear in the air, even with chocks.
One bump-stop pedestal had completely rotted away, and the other was hanging on by a thread, so replacements needed for those as well as the front eye bolts. Reassembled everything with Waxoyl, turning to a clear liquid on what was a very warm day. As on the V8 with the front eyes mounted the rear shackles lined up with the chassis rail holes without compressing the spring, neither did the shackles lock under the chassis rail when I jacked up under the spring to fit the U-bolts and bottom plate. Again the U-bolts and plates were the biggest fiddle, getting them lined up, and getting the 'bump' in the top plate lined up with the hole in the bottom of the axle spring-pad. The factory anti-roll bar makes this slightly more difficult as you can't move the axle fore and aft directly, you have to rotate the whole axle to move the spring mounting pad into position over the spring. The second side is even worse as with the first side fitted you can't even do that, and a firm push from a foot on the brake drum was needed. One thing I noticed is that the new front bolts are only just long enough, and that is with the old nuts and lock-washers. Nylocs were supplied with the bolts but to be honest I don't think they were long enough to get the requisite minimum three threads clear, as it was the end of the bolt was just shy of the end of the nut. Other than that (well, there are only the shackles left!) it all went back together inside the hour, and that includes wheels on and tools etc, put back in the garage.
Herb Adler tackles the same problem.
Spring and rebound strap appearance with normal loads
Currently there seems to be a real spate of problems (but see this), and people in the UK are beginning to complain of the same thing. You should be able to fit the rebound straps by jacking each spring up under the body - without any extra weight in the boot - before the body starts lifting off its supports. On UK-sourced springs I have done this without difficulty, even putting the harder rubber-bumper springs on a chrome-bumper car. Similarly people have asked how to get the shackles pointing to the rear instead of the front. Again it is a matter of spring hardness - the correct springs should be almost flat with just the weight of the unladen body, and as they take the weight of the body and start to flatten they will move backwards. If the weight of the car is on its wheels, even unladen, and they aren't pointing slightly backwards, the springs you have are simply too hard or over-arched for your car. However it occurs to me that all the work I have done has been on a chrome-bumper car. With the lower shackle mounting position relative to the chassis rails of rubber-bumper cars it is possible that these can lock in the fully forward position unless levered downwards while jacking slightly higher. However once the rebound straps are fitted this shouldn't occur again. Updated August 2007: Since writing this I've had to replace the rear springs on the V8. Having now bought three sets of springs from three different suppliers and fitted them to two different cars I have never had any problems using simply the weight of the body to compress the springs enough to attach shackles, damper drop-links and rebound rubbers, and this includes fitting harder RB roadster springs to a CB roadster. Nor have I had any problems with the shackle 'locking up' in a forward position on either CB or RB car. See Rear Spring Replacement.
My problem has been the opposite - ride-height too low and grounding over 'sleeping policemen' and rough ground particularly when laden (we use the car frequently for holidays with a comprehensive tool kit and trolley-jack as well as luggage). I had tried and removed rubber-bumper roadster springs as part of another exercise which raised the ride height just fine, but being harder they gave a very unpleasant choppy rise over some surfaces. In July 2003 I modified some shackles by 'cutting and shutting' to give about an inch extra height at the rear, as described below in 'Extended Shackles'.
Ride Heights round the World
Note: It may seem obvious but the static ride height of a car depends on how much weight is on the suspension. Take the engine, gearbox and seats out for example and you remove a good quarter of the weight. The body will rise on the springs, probably to the limit of the rebound rubbers at the front and the rebound rubbers at the rear. On both my RB V8 and CB roadster this results in there being very close to 17.5" from the centre of the hubs to the bottom of the trim strips, front and rear.
|| 63 roadster || 14.25 || 14 || 13 3/4 || 13.375 || Rob van der Linden, Cambridgeshire || Original springs, 60k
|| 64 Roadster || 13.75 || 13.5 || 15.375 || 14.5 || Mike Jones, Malaga, Spain || All new springs and bushings. First two sets of rears from MGOC were 2" too high, 3rd set MGOC got from British Springs.
|| 66 Roadster || 14.5 || 14.25 || 14.25 || 14 || Bud || 66 Roadster(?) || 12.75 || 12.75 || 15 || 15 || Max Heim || Original Fronts, new rears, 175R-14 tyres.
|| 67 GT || 14.5 || 14.5 || 14.25 || 14.25 || Barrie Parkinson || Rebuilt front end with V8 bushings, stock springs. Rear all new plastic bushings and fibreglass springs. No bumpers, alloy head, no spare, 1 battery.
|| 68 GT || 13.625 || 14 || 15.5 || 15.5 || BobMunch, Boise || 68 GT || 14.25 || 14 || 13.625 || 13.625 || John Hubbard, Huntsville, Alabama || The fronts are up from 13.625 following a front-end rebuild. The wishbones and pivots were badly worn, see John's pics
|| 69 Roadster || 14 || 13.75 || 14.75 || 15 || Tony Elphick, Wagga Wagga, Aus || Standard. Rears reset 15 months ago, fronts new
|| 69 Roadster || 14.5 || 15 || 13.5 || 14.25 || Miguel Clemente || 50k miles, all original except for front bushes.
|| 70 Roadster || 13.875 || 13.975 || 14.25 || 14.5 || Joe Lucas, Winipeg, Canada || Stock all around except for new bushings front & back. Spare tire on board, single 12 volt battery in place.
|| 70 Roadster || 13.875 || 13.875 || 14 || 14 || Peter Baker, UK || Heritage shell 20k, spare tire on board, single 12 volt battery in place.
|| 71 GT || 14 || 14 || 13.75 || 14 || Bill, Montana || Front springs new, rears original with new bushes and pads. 200k+miles
|| 71 GT || 13.5 || 13.375 || 14.375 || 14.5 || Bob Wilson || Fronts (red) 3k, rears (original?) 113k?
|| 72 Roadster || 12.8 || 12.8 || 10.24 || 10.24 || Richard Thompson || These seem very low but are off Richards own site and converted from cm at 2.54cm to the inch.
|| 72 Roadster || 14.875 || 14.875 || 14.75 || 14.75 || Iain MacKintosh || 72 Roadster || 13.125 || 13 || 14 || 14 || Stan, Bucks, UK || 68k, fronts look original, rears have been replaced but look flat
|| 73 Roadster || 14.5 || 14.5 || 14.25 || 14.5 || Paul Hunt, Solihull, UK || Original fronts (120k+miles?), new rears (20kmiles), new rear bushes
|| 73 Roadster || 14.25 || 14 || 15.125 || 15.125 || Paul Hunt, Solihull, UK || RB Roadster front and rear, red poly bushes at rear, 10k miles
|| 73 Roadster || 15 || 14 || 15.375 || 14.313 || Ken Earnhardt, USA || All worn suspension parts replaced. New rears fitted.
|| 73 Roadster || 14.875 || 14.5 || 14.875 || 15 || Ken Earnhardt, USA || New fronts fitted to the above, at which time the RH rear was found to be too high, the spring having a greater arch. LH and RH rears swapped over. Updated figures after a little settling, 165SR-15 tyres in use.
|| 73 GT || 13.5 || 13.5 || 14 || 14 || Paul Tegler || 73 Roadster || 14.25 || 14.5 || 13.875 || 14 || Richard Smith, USA || New Victoria British rears c1994, original fronts. Rears originally too high and at the limit of rebound straps, settled since. 185/70 x 14 tyres rub slightly on left-hand rear wing.
|| 73 GT || 14.75 || 14.75 || 14 || 13.5 || Kerry Schofield || 78k recently rebuilt by MG specialist
|| 73 GT || 15 || 15 || 15 || 14.25 || Kerry Schofield || MGOC parabolics at the rear with GAZ dampers. At the front I have had Frontline castor wedges fitted and no other change. (4th Feb 2017)
|| 74 GT || 14.25 || 14 || 14.25 || 14.25 || Steve Cioffi, Everett, Ma || Original springs, all new bushings and mountings
|| 74 CB V8 || 15.5 || 15.25 || 15.25 || 14.75 || Gordon, UK || LHR bush collapsed, replacement pending, possible mods
|| 75 Roadster(?) || 15.5 || 15.5 || 16.125 || 16.125 || Bob Hacker, Vancouver, Washington || Stock springs, V8 bushes
|| 75 GT V8 || 14.5 || 14.625 || 15.125 || 14 || Paul Hunt, Solihull, UK || Original, LHD sag on a RHD!
|| 75 GT V8 || 14.5 || 14.625 || 15.375 || 15.6875 || Paul Hunt, Solihull, UK || New fronts and rears, 5k
|| 75 GT V8 || 14.5 || 14.75 || 15.125 || 15.25 || Colin, UK || Pretty standard apart from Koni dampers, springs probably original, 77k
|| 75 Roadster || 15.5 || 15.5 || 16.5 || 16.5 || Dave Tetlow, Bucks UK || CB & V8 conversion, CB springs, still trying to reduce ride height
|| 75 Roadster || 13 || 13 || 13.75 || 13.75 || Dave Tetlow, Bucks UK || As above, but now with 1" shortened V8 front springs, reverse-eye rear springs. Standard dampers with uprated valves, 15" MGC wheels with 185-65 tyres.
|| 75 Roadster || 13.3 || 13.6 || 15 || 15 || John Tampkins || CB conversion, MGOC lowered front springs, chrome bumper (100lb/in) parabolics at the rear with all the shims above the springs.
|| 76 Roadster || 14.625 || 14.5625 || 15.625 || 15.5625 || Barry Kindig, Escondido, CA || New springs all round, 1.25" lowering blocks at rear, 185R70 14 tyres
|| 76 Roadster || 13.25 || 13.25 || 14 || 14 || John Leader, Austin, TX || Lowered fronts from BritTex, 2 1/2" lowered rears from Moss. Pirelli P6000 205/55 15 on Minilite. 28psi front, 31psi rear.
|| 76 || 14 || 14 || 14.5 || 14.5 || Mark Garret, UK || Lowered fronts, lowered parabolics on rear (all plates on top of springs), Spax all round.
|| 77 Roadster || 15.25 || 15.125 || 15.625 || 15.75 || John, Brisbane Australia || 78 Roadster || 14.56 || 14.96 || 14.96 || 15.55 || Peter Bird || 79 Roadster || 14.5 || 14.5 || 15 || 15 || Martyn Harvey, Ontario Canada || V8 conversion, early GT fronts, de-arched GT rears.
|| 79 Roadster || 14.25 || 14.25 || 15 || 15 || Mike Cook || V8 conversion, late GT fronts, lowering blocks on original rears, 79k miles.
|| 79 Roadster || 14.75 || 15 || 15.75 || 15.125 || Lars-Erik Kallstrom || Front: Moss Road uprated springs AHT21, V8 bushes, 500 miles. Rears standard, 70k miles.
|| 80 GT || 15.875 || 15.875 || 15.875 || 15.875 || Ray Swadling || Standard springs with poly bushes all round, 800 miles.
By-the-way. The V8 always had a higher ride height to compensate for its reduced ground clearance. At the front this was achieved by using a special cross-member, which eventually became the cross-member on all rubber-bumper cars, and at the rear by using lowered spring mounting points. Clausager states that the V8 ride height was not altered with the introduction of rubber bumpers. My rubber bumper V8 has lowered front and rear hangers for the rear springs, but I have it on good authority from Kelvin Dodd that a chrome bumper V8 he has seen definitely only had the lowered front hangers, the rear hangers were standard. Subsequently confirmed on two CB V8s I was able to inspect. If the rear hangers were altered for rubber bumper V8s, i.e. to make them the same as rubber bumper four-cylinder cars, then there would have been a change in V8 ride height. The rebound straps didn't change on the V8 with rubber bumpers which implies axle travel was the same, and the 4-cylinder cars adopted the V8 straps for rubber bumpers which implies they got the same suspension travel. However 4-cylinder cars seem to have used the same bump rubber pedestal all through, whereas the V8 originally had it's own pedestal for chrome bumper which changed to the 4-cylinder item for rubber bumpers, which implies a change in suspension travel between V8 chrome and rubber bumpers. Likewise the 4-cylinder seems to have kept the same damper drop link all through, whereas the V8 changed between chrome and rubber bumpers, both being different to the 4-cylinder item. V8 springs were always different and changed between chrome and rubber bumpers.
Converting RB to CB. Added January 2008
A number of factors to consider here:
In July 2003 I decided I had to do something about it. I did have rubber bumper roadster springs on for a while (part of another exercise) and whilst these gave me the extra height they were also harder and gave a choppy and unpleasant ride over some surfaces and eventually the proper springs went back on. I considered re-arching these springs but felt that would be a bit hit and miss. The alternative was longer shackles. I was surprised to find that rubber bumper and chrome bumper cars used the same shackles. Seeing as how the front eye is only about an inch or so lower, but the car is 1 1/2" higher, the extra must come from extra spring hardness and/or arching and this does seem to be the case on my RB V8. I did find some adjustable shackles but they are very expensive, more than I was prepared to spend. A few enquiries elicited no other sources of longer shackles, other than paying an engineering shop to produce some, or modifying standard ones myself.
The very expensive adjustable shackles mentioned above have three pairs of holes for the bottom pin, which is just a long bolt going through both plates. The originals have the pins pressed into splined holes in the shackle plate and the pins have a double shoulder at the threaded end, the smaller of which fits into the hole in the closing plate. This keeps the threads away from the side of the hole so protecting them, but more importantly makes the tightened shackle a rigid parallelogram, aiding spring and hence axle location. Plain bolts will allow the rectangle of the closed shackle to be distorted into a rhomboid during cornering, which will give more lateral movement of the spring and hence the axle. Over time this will tend to make the holes in the plates oval and wear grooves in the bolts so weakening them. There is also the issue of tightening the shackles. Even when the original shackle is tightened to 30 lb.ft. the bushes are only lightly nipped and there is clearance for the spring eye to pivot on them. But without some form of spacer tube a plain bolt is going to tighten the shackles onto the bushes and spring eye, restricting movement, and probably damaging the bushes in a short time.
I decided to modify some myself. But rather than cut up and weld a piece into my existing ones I bought two pairs of the standard items and used those. This was for two reasons - I wanted a 'proper' set to go back to if I needed to, and I wanted only one weld in each rather than two. In the event it was an easy enough job and if I were doing it again I would extend the existing pair with two welds and a piece of flat bar and save myself £40.
The first job was to decide how long - the distance between the centres of the shackle pins - I wanted them to be. The standard items are 2.5", I wanted about an extra inch as measured between the hub centre and the bottom of the chrome strip, and given the various angles and lengths of parts I reckoned on about 1.25" longer at the shackle, i.e. 3.75" in total. I didn't want to guess and get it wrong but be a bit more scientific, so I made up two wooden blocks to go between the spring eyes and the chassis rails, shackles removed, then added and removed further wooden 'shims' until I got my 1" extra between hub and trim. This was a bit of a fiddle, jacking and lowering the spring and axle, but fortunately I got it right on the second go. I then measured the distance between the centres of the holes in the chassis rail and spring eye, and it turned out to be 3.75". Oh well, at least I knew it was going to be right.
At this point a word about removing the springs. I say 'removing' but I didn't actually remove them altogether, the front bolt was all that was left so the following process is good for complete removal too:
By putting wooden blocks between the spring rear eyes and chassis rails and varying the thickness of the blocks with shims, supporting the springs under the axle on jacks and lowering the car till the tyres just touch the ground, you can get a reasonably accurate measurement of the distance between the centre of the hub and the bottom of the trim strip as it will be in normal use. The distance between the centres of the holes on the spring and chassis rail then determines the required shackle length. With a pair of dial calipers I used the outside jaws to measure the distance between the closest part of the two holes, then used the inside jaws to measure the furthest part, halved the difference and added that to the lowest figure to get the centres.
By cutting and shutting two pairs of shackles, as I was, you then have to determine where to make the cut. I felt it best to make each half the same length, which meant half of 3.75" i.e. 1.875" from the centre of one of the pins. Careful measuring, scribing and cutting produced the pieces as shown in the picture on the left (click to enlarge). As well as the pieces from four shackles which are going to be welded together to produce two, you can also see an example of the discarded parts of each shackle. 3/75" is just inside the flat part of the shackle plates, much more and you would be cutting across the dished part (which is no big deal but it would look a bit odd when welded together), and you only have about 0.25" available anyway before you reach the pin. Don't weld half of a closing plate to half of a pin plate as I have the top ones laid out! I didn't, but only noticed I had them laid out incorrectly when viewing the picture when I came to write this account.
I wanted to grind the welds flat after fabrication, so to get maximum strength from the weld I ground both sides of each cut edge at an approximate 45% angle to make a 'V' groove each side when the pieces were put together, as shown in this picture. Not terribly clear, but you should be able to make them out.
Next came the job of welding them together. I decided to do the shackle plates before the closing plates as I considered the former easier to get aligned with reference to each other, then the closing plates can be aligned with reference to the welded shackle plate. The shackle plates need to be aligned such that the pins are parallel in two dimensions - one so that the centres of the pins are the same distance apart for the whole of their length, and the other so that the two pins are at the same angle when viewed one behind the other. Finally the two halves of the shackle plate should be as level and flat as the previous two alignment criteria allow. I opted for holding them lightly in a vice across their width, tapping first one then the other until all three criteria were met, then tightening the vice and making sure they were still correctly aligned. Because I was welding two halves of different shackles together they were of slightly different widths which meant that when one was tight in the vice the other was still loose, so I used some thick card as 'soft jaws' which deformed and gripped each half with relatively equal force. I MIG welded one side filling the 'V', checked the alignment again, then turned them over and welded the other side filling the other 'V'.
The closing plates are less critical, only having to get them flat and level, and using the completed shackle plates to ensure that the holes are at the correct centres. The welded and ground parts can be seen here.
All that remains is to fit them. With the U-bolts undone and the spring tension released you should be able to insert the shackles and bushes into the spring eye and chassis rail quite easily. Because they are longer than the originals and because the spring may be resting on the previously removed damper locating plate in its forward position, you may have to pull the rear end of the spring down a little against its tension in order to get the shackle in. You may also need a little Waxoyl or washing-up liquid on the bushes to act as a lubricant to aid insertion. Don't use oil or grease as it will rot rubber. Fit the closing plate, spring-washers and nuts. When tightening the nuts they may tighten up before the shoulder on the pin has located itself into the hole in the shackle plate, then come looser as they locate properly, before finally tightening up to 30 lb.ft.
Jack the spring up under the axle, fit the spring locating plate and damper mounting plate onto the U-bolts, and fit and tighten the U-bolt nuts. The Workshop Manual shows double-nuts which can be locked together, but Nyloc nuts seem to be fairly common these days. Some say Nyloc nuts should only be used once, but I have seen a reference in a manual that says as long as you can't turn them with your fingers they are fine to reuse. If in doubt replace them. All that remains is to jack under the axle so you can remove the body supports, lower the wheels to the ground, and measure your new ride height after a short drive to settle things. After a longer drive recheck the tightness of the shackle and U-bolt nuts. The fitted shackles can be seen here, pointing slightly to the rear, and not far off right-angles to the spring which is nearly flat.
A comparison of 'today' (February 2017) with when first modified, after some 14 years and 25k miles.
Spring Specs Updated October 2008
|Car||Free Height||Spring Dia||Free Coils||Loaded Height||Load Weight||Rate lb/in||OE Part No.|
|Pre-72 Roadster||9.9||3.238||7.5||7||1030||348||AHH 6451|
|Pre-72 GT||9.1||3.28||7.2||6.6||1193||480||AHH 5789|
|72-on CB GT||9.32||n/a||7.2||6.84||1193||480||BHH 1077|
|73-on Roadster||10.2||n/a||9||7.44||1030||373||BHH 1225|
|RB GT||10.2||n/a||9||7.44||1030||373||BHH 1225|
|V8 (all)||9.32||n/a||7.2||6.84||1193||480||BHH 1077|
1. Information from Clausager, Factory WorkShop Manual, Factory Parts Catalogue, Special Tuning Manual, and Haynes.
2. The 73-on Roadster, CB and RB, and RB GT all had the same front springs as indicated above.
3. 'Loaded Height' is at the specified 'Load Weight' i.e. partially compressed. The difference between the free height and loaded height is the deflection, or the working load divided by the rate.
4. Clausager refers to the 1972 change as a 1/2" increase to all models to prevent excessive settling on export models when lashed down on ships decks for long periods, however the workshop manual shows a change of about 1/4" at that time.
5. Clausager makes reference to what he calls a 'Part number change only' in November 1972. However the Workshop Manual has three sets of specs for the CB roadster - I have assumed (maybe wrongly) that the third set is in fact the November 72 set that Clausager mentions. I have called these '1973 Roadster'. Dave Wood states he received a recall notice for his 72B later that year for a spring change to raise the height by 1/4" to meet minimum headlight heights which would seem to concur with the workshop manual. The Parts manual only has two part numbers covering the change early in 72, not the change in November 72.
|Car||Leaves||Interleaving||Width||Gauge||Load (flat)||Rate lb/in||Deflection in||OE Part No.
to May 63
|5 + bottom plate||None||1 3/4"||0.2187in||400lb||99||4.04||AHH 6453|
May 63 on
|5 + bottom plate||1/2 2/3 3/4||1 3/4"||email@example.com,|
|CB GT||6 + bottom plate||1/2 2/3||1 1/4"||firstname.lastname@example.org,|
to Sep 75
|6 + bottom plate||1/2 2/3||1 3/4"||email@example.com,|
||RB GT||6 + bottom plate||1/2 2/3||1 3/4"||firstname.lastname@example.org,|
Sep 75 on
|5 + bottom plate||n/a||n/a||n/a||n/a||n/a||n/a||BHH 1779
||CB V8||6 + bottom plate||1/2, 2/3, 3/4, 4/5||1 3/4"||email@example.com",|
||RB V8||6 + bottom plate||1/2, 2/3, 3/4, 4/5||1 3/4"||firstname.lastname@example.org",|
(lowered AHH 7346)
1. Information from Clausager, Factory WorkShop Manual, Factory Parts Catalogue, Special Tuning Manual, and Haynes.
2. Although the roadster originally is described as having five leaves and a bottom plate ('six leaves' elsewhere) and the GT is described as having six leaves and a bottom plate ('seven leaves' elsewhere) both the 63-on CB roadster and various GT springs are described as having 3 leaves of each thickness. This seems contradictory, and the roadster did get shorter U-bolts when it reverted to the previous number of leaves in September 1975.
3. These springs are listed - without prices - by GB Springs as 'Heritage Car Springs', with some variations from the original part numbers. Some of these seem to be where the spec was changed for a particular model, only the later spec is now supplied, for example only one CB roadster spring is listed whereas until May 1963 a different spring was used. Also they don't list a CB GT spring but it was the same one used for early RB roadsters i.e. AHC 31.
Unloaded Rear Spring Dimensions
|A||eye centre to eye centre||41 1/4"|
|B||inverted height from floor to top of top spring||8 5/8"|
|C||front eye centre to pin top centre||19 1/8"|
See also the picture on the right of the table.
Remember these are relatively new rubber-bumper roadster springs, but all others should be close. If your dimension A is significantly less and B is significantly more then over-arching is the problem. If the dimensions are close but you still cannot compress them enough during installation, or the resultant ride-height is much too high, then the leaves are much too hard. In either case get your money back and source them from a reputable supplier in the UK.
Update January 2013: By now it's probably best to leave off the 'in the UK' as people here are getting duff springs as well. But Mark Bates in the US had the 'submissive monkey' stance, the rebound rubbers were pulled taut and snapped while parked. He removed them and found that dimension B - the arch - was fully an inch and a half more than mine. He purchased another set from The B Hive in America and they do have very similar unloaded dimensions to mine.
See also Front and Rear Suspension Considerations from Doug Jackson's British Automotive site.
Types: Updated September 2013 According to Clausager four different types of column and wheel hub splines were used over the years, and are not interchangeable. However he gives the four types as 62 to 67, 67 to 69, 70 to 76, and 77 on - model years where appropriate. The Parts Catalogue doesn't entirely bear that out, but it has its own gap in the information. There are two sections for 4-cylinder columns and wheels - one described as 'Not North America or V8' and the other as 'North America collapsible type'. However Clausager states that the North American collapsible type wasn't used until the Mk2 of 1967, which if correct and because there are no parts listed for North America before it got the collapsible column, indicates that all models used the same types for the Mk1, and that is what I have assumed. The Parts Catalogue is also quite clear that the same spoked wheel and columns were used in non-North American markets until the start of the 1970 model year. So whilst North America used one type for the Mk1, and another type until the start of the 1970 model year, other markets used the same type from the start of production to the start of the 1970 model year.
Originally the column was solid i.e. non-collapsible and did not have a steering lock and ignition switch. RHD and LHD for all markets used the same components which consisted of a separate inner and outer. Various non-North American countries got steering locks at different times between 1962 and late 69, and hence had different inners and outers, which also differed between RHD and LHD. These used wire-spoke wheel AHH 9284 which was used until 1970. In 1967 North America got a collapsible column for the Mk2, with what Clausager describes as 'an easily defeatable' steering lock. Still with the wire-spoked wheel, although this wheel has a different part number AHH 9825, implying it was different to the non-North American parts. To my way of thinking this makes all markets for the Mk1, and non-North American to the start of the 1970 model year using the first variant, and North America Mk2 to the start of the 1970 model year using the second variant.
In 1970 non-North American inners and outers changed. There were still locking and non-locking variants, and hence RHD and LHD locking variants. North America got a different column with improved, side-entry lock. From 1st January 1971 the UK required a steering lock, so a column with a front-entry lock was fitted to cars for all markets except North America. For the 1972 model year in non-North American markets the column changed to a collapsible assembly rather than separate tubes and shafts. The wheel for all markets had alloy spokes with five holes in each from 70 to 72, changing to slots for the 73 model year, but only a few months later the slots were changed to depressions. V8s had the side-entry lock on the full energy-absorbing column, and the wheel with depressions for the whole of production. From the start of rubber bumper production all cars regardless of market got the full energy-absorbing column (crushable outer as well as collapsing shaft) with side entry lock. The components then remained unchanged until the end of the 76 model year. As the wheels and columns have different change points, and the Parts Catalogue indicates the wheels were common to all markets, V8 and 4-cylinder, they must have been compatible, so this is the third variant - 1970 to 1976. I've been able to compare a 73 roadster and a 75 V8, and whilst the wheels fit on each others splines the taper seems to be slightly different, even though the change-points indicate they should be the same. With the 'right' wheel pushing the wheel down onto the taper locks it, whereas with the 'wrong' wheel even pushed down it wobbles from side to side very slightly, which is probably because the V8/RB column is almost 6mm wider. 1975 Jubilee GTs may have had an all-black wheel with a gold MG horn-push logo. Other cars built during the 1975 Jubilee year had the metal-finish spokes with the gold logo.
For the 77 model year the column and wheel (now with four rubber-covered spokes) changed, again common to all markets, giving the fourth variant - 1977 on. However this is more to do with completely different arrangements for cancelling the indicators and sounding the horn, the splines and threads appear to be the same. The MG logo was originally dark grey, then silver as standard. UK 1980 LE models had the standard wheel but with a red MG logo. North American Limited Edition models of 79 and 80 had a wheel similar to the 70 to 72 but with three holes instead of five.
I have found the following list concerning North American cars which agrees with the change-points above:
||62-67 ||3/4" by 48||11/16" X 27 TPI||1 5/16" or 34mm
||68-69 ||5/8" by 36||9/16" X 27 TPI||1 1/16" or 27mm (to be confirmed)
||70-76 ||11/16" by 36||9/16" X 18 TPI||1 1/16" or 27mm
||77-80 ||11/16" by 36||9/16" X 18 TPI||1 1/16" or 27mm
Interestingly the 'collapsible' columns before the full energy-absorbing allow the shaft to move freely up and down within the inner. So in any frontal impact an unbelted occupant could push the wheel forwards, collapsing the inner and crushing the switchgear, allowing more travel before hitting something solid but little energy absorption i.e. deceleration. If the collision is so severe as to move the rack rearwards the steering wheel and inner shaft would actually move towards the occupant, possibly allowing even a belted driver to hit it, although that would collapse the inner shaft. The later full energy-absorbing columns are different in that the inner cannot move in and out of the outer. An unbelted driver will probably suffer greater injury from this type of column as the wheel cannot be pushed forwards until there is sufficient force (from the driver!) to deform the structure the column is bolted to. If the rack moves backwards then the inner will shear with very little force, and no energy absorption as before. It's only if the toe-board comes back far enough to hit the bottom of the column outer that the mesh construction of the outer will do its energy-absorbing stuff, and prevent the wheel moving towards the driver. But it's difficult to see how that could happen, except possibly in a V8 where the engine moves backwards. If the impact is severe enough to deform the toe-board, even with a V8, it's difficult to see how the energy absorbing column is going to make much difference to the injuries of the driver, given that this 130kph/75G impact of an MGB with a solid concrete wall resulted in no intrusion into the cabin.
Failing that you may have to drop the steering column by undoing the three column to dash bolts - not the three toe-board bolts. If you do that, be very sure to note where any packing is present between column and dash, as that is part of column UJ alignment. Be sure not to let the column 'hang', only lower it enough to get at the screws, then temporarily refit it to support its weight.
The toe-board bolts just clamp a plate and rubber seal to the toe board, with a sliding fit to the column, they are not clamping that end of the column in position. Normally one would expect the seal to be pressing on the column with equal force all the way round, which will help keep that end of the column in the correct position when the upper part is disconnected or slackened. But just in case it is pressing on one side more than another, e.g. if those bolts were tightened before the column was fully aligned, it might be an idea to slacken and retighten those first to even out any forces, and only then undo the column to dash bolts.
On Vee the position of the column is such that the right-hand screw is shrouded more than the left-hand, so it's possible that just by slackening the column to dash bolts, you may be able to slide the column first one way then the other for the best access to each in turn. Note the positioning first, and put it back to that when you finish. If in doubt you may need to check the alignment of the steering column UJ.
Steering Lock: December 2014
See also Ignition Switch
What lies inside
|May 62 - Aug 68||101-152454||Germany, Finland (Oct 67), Austria (Jan 68)||13H4180||27H6237||Use BMK2259||Spades on switch
||Aug 68 - Dec 70||152455-231338||Above plus France (Sep 69)||13H4862||27H6237||Use BMK2259||Spades on switch
||Dec 70 - Feb 72||230617-275645||Not North America or Sweden||BHA5709||Use BMK2259||Combined lock and switch
||Feb 72 - Sep 74||275646-361000||As above||BHA5215||37H7708||Use BMK2259||Spades on switch
||May 62 - Sep 74||101-361000||As above||BMK2259||37H5934||Spades on switch
||Sep 74 - end||360301-on||As above||BHM7056||BHA5398||Note 1||Lock with switch, multi-plug
||V8||18G8905||Note 2||Lock with switch, bullets
||May 62 - Aug 68||101-152454||Sweden||13H4180||27H6237||BMK2259||Spades on switch
||Aug 68 - Dec 70||152455-231338||As above||13H4862||27H6237||BMK2259||Spades on switch
||Nov 67 - Sep 69||138401-187840||North America||BHA4715||37H4114||Lock and switch NLA
||Sep 69 - Aug 71||187211-258000||North America, Sweden (Dec 70)||BHA5050||BHA5056||Alternatives||Lock and switch NLA
||Aug 71 - Aug 72||258001-296000||As above||18G8906||Combined lock and switch
||Sep 69 - Aug 71||187211-258000||As above||18G8901||BHA5070||Lock and switch NLA
||Aug 71 - Aug 72||258001-296000||As above||18G8905||BHA5070||Lock with switch, bullets
||Aug 72 - Aug 73||294251-324942||As above||18G8984||BHA5128||Bullets on wires
||Aug 73 - Aug 73||324943-325855||As above||18G9064||BHA5288||Lock and switch NLA
||Aug 73 - Aug 73||325856-328800||As above||18G9118||BHA5288||Lock with switch, multi-plug
||Aug 73 - Jun 76||328110-410000||As above||18G9119||BHA5292||Multi-plug
||Jun 76 - end||410001-on||As above||18G9119||BHA5069||Multi-plug
Note 1a: Lock is now BHM7144 complete with switch. This is the North American lock and switch with extra grey and purple/pink wires, the original may have the grey but not the purple/pink. The remaining four wires should connect directly to the same colour wires in the main harness, but double-check before plugging in. The grey and purple/pink should not have corresponding wires in the other half of the UK multi-plug.
Note 1b: Switch no longer available, use BHA5292. Again this is the North American version as above.
Note 2: Prices for replacement lock with switch for the V8 varies from £31 to £120! If only the switch has failed it may be worth trying BHA5292 as they can be had for little more than a tenner, and if it fits it saves having to cut off the lock which cannot be done by drilling up from below like it can with the earlier side-entry locks. You would need to cut off the multi-plug, discard the grey and purple/pink wires, and solder bullets to the remaining brown, white/green, white and white/red wires.
Lock replacement: Note this process is only suitable for chrome-bumper 4-cylinder cars as the thread end of the bolt can be accessed from below. On V8 and rubber bumper cars the lock covers this and the bolts have to be removed from the head end.
When Bee came to me there was only one ignition key so I had a spare cut from that. It worked, but over the years as the lock has worn on the rare times I use it I have found that it is very difficult to turn the lock all the way back and remove the key as normal. This earlier 'front-entry' lock needs a twist-push-twist-pull to turn the accessories off and remove the key, but this key wouldn't do that, it would come out too soon. As well as leaving the ignition switch then capable of being operated with a screwdriver, I cannot get the 'good' key in, so have to persevere with the 'spare' key - which fortunately does go back in, wiggling and turning gently until finally the lock does fully return, the key comes out as it should, and the 'good' key then works again. OK, so don't use the spare key, and get another one cut and hope that would work. Well the 'good' key is itself a copy and not original to the car or even of the same type, so what with that and 40 years of use on the original lock I decided to replace the lock now rather than wait until it properly jams, which is almost bound to be at an inconvenient time. Vee has a side-entry lock with a push-button release.
The original lock is quoted as being BHA 5215 (chrome bumper Feb 72 on), with BMK 2259 being a universal replacement for that and others. Googling BHA5215 showed loads of suppliers, ranging in price from £59 to (gulp) £107. The good news was that I wanted to get mine from Leacy's as part of a shopping list it was worth going to collect and they were the cheapest. The bad news was they were out of stock! As the Irish shopkeeper said, "Well when we don't have them in stock ours are cheap too". So I looked up BMK2259 at Leacy's, the good news being they were in stock, the bad news being they were (even bigger gulp) £154! So I rang them, and apparently those part numbers include the ignition switch, and it was the switches that were unavailable for the BHA 5215 version. They have the bare locks listed separately as BHA5215X, but only on their stock system, not on the website. So he looked up those, the good news was they had them in stock, and the even better news was that minus the switch they are only £43!
These locks have special shear-bolts clamping them to the column. They may still have the heads attached which will seem odd. Many years ago I queried the fact that on my Mum's new Mini they still had the heads, and shouldn't they have sheared off when being tightened? Apparently not, they are supposed to shear if anyone attempts to undo them. However the heads were missing from Bee's. I was thinking that I would have to remove the steering column as I didn't want to use an angle-grinder in the cabin. But having a look I could see that the bolts are angled downwards and to the drivers side of the car, so conveniently placed for drilling along the length of the threaded part. Furthermore the shanks of the bolts stopped about 1/4" short of the hole they were in, which makes a useful drill guide, so drill in-situ it was. However! The first thing I had done was to test both keys operated the new lock and the bolt smoothly, don't want to wreck the old lock then find the new one doesn't work.
I needed to move the indicator stalk sub-harness out of the way, and unplugging it from the main harness seemed easier than removing the cowl and the switch from the column. However the black rubber moulded plugs and sockets stick together quite well and it was difficult to get a good grip on both halves. Then I had the idea of using external circlip pliers to lever the two halves apart, which took about one second!
Lock replacement:With that out of the way I decided to remove the switch from the back of the old lock, so that vibration etc. from drilling didn't damage it. There is a small screw going downwards at an angle from the drivers side, through the body of the lock and into the switch. A little fiddly to get at, I used a hex drive screwdriver point in a very small ratchet. It's small, don't lose it. With that out I eased the rubber boot off the lock and the switch came away. I then offered up the switch to the new lock - there is a key and key-way that has to be aligned - and checked that with the battery cut-off switch back on the accessories, ignition and cranking all worked. Again you wouldn't want to complete the installation to find it didn't.
I decided to use a 4 or 5mm drill to start with, even though the threaded hole is about 6 or 7mm, as a smaller drill goes through easier, then its hole acts as a guide for the larger drill. Drilled first one screw then the other with the small then the large drills until going by the depth I reckoned I was just past the join of the two halves that were clamped around the column. By now the lock was moving back and fore slightly round the column, tried levering against the column tube with a pry-bar, but not too hard. Drilled some more until I was sure the large drill was fully past the join, levered again and it fell off. It really didn't take me much more than an hour. I had managed to drill right up the middle of one bolt, and only slightly off to one side of the other. Note that this can only be done with the earlier front-entry locks mounted lower down the column, not the later side entry accessed through the cowl as the bolts are in line with the lock instead of being at right-angles to it.
Nothing more to do except position the new lock - which is a Lowe and Fletcher just like the original - onto the column, and do up the bolts no more than finger-tight as again I didn't want to complete the installation i.e. fully tighten them until I was sure everything worked. The clamp part has an offset hole, which seems to go to one end of the lock.
Fitted the switch into the back of the lock and inserted the screw ... and the switch came back out again. Had a couple of goes, but it still wouldn't go into the matching hole in the switch body, and I was beginning to think that the alignment was wrong. But with the screw going in partly from above with all the wiring there it wasn't that easy to hold the switch into the lock with one hand while positioning and turning the screw with the other. So I slackened the lock clamp bolts sufficiently for the lock to hang down which put the screw at a much more convenient horizontal angle, and it went straight in. Again tested the operation of the switch with both keys and all was well, so repositioned the lock and did the bolts up finger tight again. This time I turned the column, keys out, so that the bolt engaged and locked the steering, then waggling the wheel to take the load off the bolt check the keys retracted it, again all good. So final tightening of the bolts, and find the bolt heads are 13mm. They are also at an angle, so whilst one is easily accessible from below, the other is virtually on top of the column. Fortunately I have a set of swivel-head combination metric ratchet-ring spanners, and the 13mm one does the job. Not enough leverage to shear the top one, which I wouldn't attempt with the ratchet ring anyway, and although I could get a standard socket on the lower one I just do them up 'tight' but not too tight. I'll leave them like that for the time being to check all is well, with a view to increasing the tightness later on.
What lies inside: Someone on the MGOC forum mentioned recently that when their key barrel fell out of the lock they drove it for some time using a screwdriver to turn the innards. It struck me that with a steering lock that might have compromised the locking mechanism, and you wouldn't want it to engage when driving along! I'd (of course) still got the faulty lock I replaced as above, and as it wasn't going to be any use for anything else decided to investigate how it worked.
The bottom line is that the barrel assembly turns a plastic cam, which as well as turning the ignition switch proper also lifts the lock out of engagement. So even with no barrel the cam has disengaged the lock once the ignition is on, and although there is no longer a spring detent to prevent the switch coming back by itself, if it does so hopefully it will cut the ignition before the lock engages! Still not a good idea to drive without a barrel though, as it is part of the barrel that positively prevents the lock coming back into engagement until you have withdrawn they key, as described here.
Getting in is tricky. There seems to be a 'lid' over the innards, with a couple of dimples that looked like they might have been filled with something to hold it in place. The metal is very soft so easily drilled, and eventually the lid levered off, leaving a side piece inside the lock. It was only afterwards that I discovered a tiny-tapered pin in the side of the lock that was actually what was holding the lid in place. That needed to be drilled out as well, but as the pin is hard and the metal around it soft eventually I had drilled round it and could pull it out with pliers, and the remaining part of the lid came out.
At that point the barrel assembly was moving slightly in the lock body, I couldn't see what was holding it in (the key was inserted), and eventually 'persuaded' it out by tapping with a cold chisel and hammer on a suitable projection. That came out, leaving two plastic components inside - a blue one carrying the metal locking peg that engages with a slot in the column shaft, and a white cam that operates the switch as well as lifting the blue part with the locking peg out of engagement with the steering column as the key is inserted and turned.
It looked like the blue part should just push out, but the edge of the peg that engages with the column shaft had peened over very slightly which made that part wider than the close-fitting slot, and needed a bit more persuasion. After that the white cam came out as well.
That allows one so see how it is the white cam that operates both the switch and initially disengages the lock, but there is another more important aspect to keeping the lock disengaged.
There is a sliding rod on the barrel assembly that is pushed into a recess in the blue part once the key has been inserted and turned and the lock is disengaged, and keeps it disengaged irrespective of what the white cam does after that. When switching off and removing the key it's only when one has gone through the turn-push-turn-pull process on this version of the lock and the key starts coming out of the barrel that this rod is withdrawn from the blue part, and the locking peg drops onto the column shaft or into its recess with a definite click. So the barrel assembly is fundamental to keeping the lock disengaged once the ignition key has been inserted and turned. The main function of the white cam as far as the lock is concerned is just the initial disengagement, the fact it can also keeps the lock disengaged once the switch has been turned if the barrel is removed is only secondary. In fact the sliding rod holds the blue part higher than some parts of the white cam, and whilst the cam will prevent the locking peg fully engaging with the column, without the barrel it does allow it to drop slightly. So depending on how much clearance there is the peg could catch slightly on the shaft slot as the steering is turned.
Indicator/turn Switch and Cowl Positioning August 2015:
Note that even slackening these clamps may well disturb the column and rack UJ alignment, which should be checked afterwards.
With the later full energy-absorbing column the relationship between inner and outer and hence the switches, striker, horn brush, cowl and steering wheel are all fixed within the column.
Repairs: The original solid and early collapsible columns have upper and lower bushes which wear and can be an MOT failure. The later full energy-absorbing columns use a ball-bearing at the top and apparently at the bottom which don't seem to suffer from the same wear problems. As far as the UK goes columns prior to the 1972 model year use upper bush GSV1095. For the lower felt bush columns without steering lock use 17H6565, and those with the lock use 13H569. The intermediate collapsible column from 1972 until the end of chrome bumper production (but not V8s) use upper bush MGP1050P and lower bush MPB1002 which is quite challenging to replace. This has been discussed several times on the MGOC forum and pictures and descriptions, and dealing with failed shear pins, have been pulled together here. Some European markets had column locks on Mk1 cars and so had different columns. North America had different columns - with locks - from the start of Mk2 production. Only from the start of rubber bumper production did all markets get the same energy-absorbing column. The remainder of this section relates to this full energy-absorbing column.
Vee's steering wheel has always had a bit of rotational play in the column. At about 6-7mm it is a good bit less than the UK MOT limit of 13mm (and a whole lot less than the 30mm specified in my Toyota Celica manual!) but I still didn't like it, for one thing it rattles over some surfaces. As well as the rotational play the steering lock has never worked in my ownership, so I was wondering if I would be able to do anything about that. The car also had a fuel pump short before my time (as had Bee and two other cars I have worked on, all with fuses now!) so the brown and white were damaged. The white only very slightly there (much worse elsewhere) but the brown has had the bullet connector for the switch harness cut out altogether and the wires spliced together. It's had various electrical bits added before my time also connected to this splice, and when I added a horn relay I added one more to it (at least mine was brown). I'd also had an alarm installed, and the fitter soldered his wires to the 12v and indicator wires on the switch side of the multi-plugs (easier to get at) so with the repairs and additions it was all a bit of a mess round the column - another opportunity.
First job was to remove the upper UJ clamping bolt, so the column shaft can be pulled out leaving the UJ behind. It's worth mentioning here that although my roadster has just a notch on the column shaft, and a groove running all the way round the rack shaft meaning the two shafts can be reassembled in any orientation which seems to be the norm, both the V8 shafts only have notches, so the UJ can only be installed in one position on both shafts - strange, but true. Loosen the other bolt right off while there is still some support from the other shaft, but leave the bolt in position so the UJ stays on the rack shaft, and the nut on the bolt a few threads so the bolt doesn't fall out!
Steering wheel comes off with the usual method. This makes it much easier to get the two halves of the cowl off, especially as the additional screws at the bottom, handily (not!) covered by the dashboard, were removed and not refitted by a PO. This is why the book says to remove the column complete with cowl and switches, which would be right pain if all you wanted to do was adjust the horn brush! In fact the book says to remove the column complete with the steering wheel as well as the cowls and switches, which is stupid if you subsequently need to remove the wheel. Unscrewed the column switches and left them dangling. At that time I couldn't see how to remove the ignition switch from the steering lock so had to cut the splice in the brown, and the alarm wire. The other ignition switch wires are on bullets, rather than a multi-plug like the column switches.
When it came to undoing the three toe-board bolts they were only finger-tight, and when I got them all out (the top one is tricky, needing two 3/8" wobble extensions) the plate wasn't attached to the column anyway, not just loose but flopping all over the place and falling right off when I finally removed the column! The hole in the plate is quite a bit bigger than the end of the outer tube it fits over, so there is no way it can align the bottom of the column to the UJ, which some say it does, but more of that later, the upshot is that simply slackening the three toe-board bolts should be all that is required to pull the column out, and leave the plate and rubber seal in-situ - much easier than completely removing all three bolts.
When I undid the upper bolts and started trying to pull the column out I could tell the lower half of the inner was staying where it was, even though I had removed the UJ bolt. I realised I would have to lever it out from inside the engine compartment so would need to support the wheel end of the column on some cord while I did so - of course no cord within reach! So I tried to put one of the upper bolts back in but even though the column bracket is slotted it was too far back to get any bolts in. Took quite a bit of pressure pushing the column down towards the toe-board against what seemed like spring pressure to get one in. When I finally got the column out of the car I found I could pull the bottom half completely out as the shear pins (actually injection moulded plastic) had done just that - hence the rotational play.
There is a spring at the bottom of the lower half, pressing back against the lower bush in the outer, and forwards against a circlip on the inner shaft, which is effectively trying to push the shaft out of the bottom of the outer all the time. Ordinarily the shear pins mean it is pulling on the upper half of the shaft, and the upper bearing on that is pulled down into the upper end of the column, as well as being retained by another circlip. That's why I had trouble temporarily getting an upper bolt back in - I was having to compress that spring by pushing the column towards the toe-board far enough to get an upper bolt in, and it's quite a hefty spring! As to when and how the pins had sheared, I don't know.
With the column finally out there is a plastic sleeve wrapped round the lower half of the column, covering the collapsible mesh section. Glued or heat-bonded with five blobs down the edge I cut through the bonds with a sharp knife, and can now see the shaft through the mesh. With the lower half of the shaft pulled out I can see the remains of the injection moulding process in two places on the upper/inner half of the shaft, and four 'nubs' of plastic sticking out of four holes (two each side) in the lower/outer part. I also find that with the lower half of the shaft out, the free end of the upper half is free to flap about inside, and in some positions the steering lock (key out) is catching, but when held centrally it is free. So I wonder if it has been attacked by thieves before my time (apparently if you don't turn the wheel to engage the lock when you have removed the key, they can wrench the wheel round and as the locking pin drops into the hole the momentum snaps it off). But later on when I have been working on the column I find the lock engaging with both parts fitted, and has to be released with the key, so maybe the locking pin is whole but just sticky. I do find the ignition switch slathered in oil, maybe squirted in to try and get the lock working. Never use oil or grease in a lock, only graphite powder.
With the column on the bench I espy a tiny grub-screw under the switch, which when unscrewed to flush with the lock housing allows the switch to be withdrawn. If you are going to be leave the switch out for any length of time screw this back in to prevent it falling out and getting lost. One oddity with the ignition switch is that with the various work that has been done on the wiring there is black insulation tape wrapped round it, which I have to remove to expose the alarm wire soldered to the brown, and I find a purple/pink wire. Now this is only used on North American spec cars, for the anti-runon valve. So whether the car has had an American column and/or switch at some time, or whether the manufacturers use a standard tail and just cut the unused wires off (there is no spare contact on the switch for this wire) I don't know. Update: The purple/pink is standard on all switches for this type of column i.e. all RB cars but there is no corresponding wire in the harness-side of the UK multi-plug.
I don't want to cut the lock assembly off the column (the shear bolts have sheared off), so wonder if I can remove the upper half of the shaft from the outer. This may allow me to see what is happening with the column lock, and possibly free it up if it isn't broken. I espy a circlip quite deep inside top of the outer, and manage to get that out of its slot. My angled internal circlip pliers won't go in that far, but by using one leg of a straight external set to lift up one end, I can then get one leg of my angled internal pair in that, and shift the other end of the circlip with one leg of my external pair. The shaft with it's bearing can then move up and down a couple of inches, but something is stopping it coming out altogether. There is an alloy casting at the top of the tube, held on with three large pop-rivets. I'm guessing I could have drilled those out, and the casting would have come out allowing the upper bush and shaft out, but don't have any replacements that size so stop short of drilling them out. Oh well, it's not had a steering lock for my 16 years, I doubt it matters now. December 2014: It was only after replacing the steering lock on Bee that I suddenly thought that it was probably the steering lock that was holding the shaft in the outer, if I had inserted and turned the key it might have come free. However when responding to a BBS request about stripping these columns I mentioned that, but he had the same problem and didn't even have his lock fitted. end of update Incidentally, the fact that the upper part of the shaft is retained in the outer this way, means that hammering on the end of the column to free the steering wheel, especially if your knees are braced behind the wheel, means that you are highly unlikely to break the shear pins, much less collapse the column. It's more likely to be a problem at the other end if you have to hammer or lever the UJ back on if the splines are stiff, but even then there is a strong spring pressing the lower shaft downwards, the same principle as bracing your knees behind the wheel.
December 2017: John Bilham had to go through a similar process when installing PAS but was more persistent than I was. He writes:
I decided to remove 'my' bearing carrier first, so drilled the heads off the three rivets hoping to just slide it off the column. That didn't work, but on closer inspection I noticed that in addition to the large inside circlip which retains the bearing (I wasn't going to remove the bearing itself), there was another small outside one sitting on the shaft in front of the inner ring of the bearing. When I removed this the carrier and bearing slid off. Looking at the exposed shaft, there is the slot for the circlip, then a rubber oil seal, similar to that on a valve stem, that the bearing sits on, and then what looks like another slot, although it's difficult to see.
When I drilled the heads off the rivets on the other, supplied, column, the carrier moved a few mm but wouldn't slide off. This column has the large inside bearing-retaining circlip but not the outside one on the shaft. I then realised the heads had come off but the rest of the rivets had remained in place and these were obviously catching on something hidden on the column. They couldn't have been very tight because they just rotated with the drill bit, and were still long enough to almost touch the shaft. Took enough off them to allow them to fall out and the bearing casing just slid off. This revealed an outside circlip similar to mine, but this was sitting behind the bearing (which was what the remains of the rivets were snagging on) but with a similar oil seal in front of it.
Further investigation by John (more than he needed to do for installing his PAS for which I'm grateful) dismantled the bearing housing into housing, bearing, shim and circlip and revealed all, click the thumbnail.
Subsequently John writes:
But back to the repair ...
I decide to slather some Araldite under and round the two halves of the nylon insert, and inside the holes in both upper and lower sections, so that when the lower half is pushed back over the upper that, and a pin through the hole, should hold the two halves together and take out the rotation play between them. Some people have said they used a hot-glue gun to replace the nylon shear-pins, but as described above there is a strong spring trying to pull the lower half of the inner out of the bottom of the outer, but the upper half of the inner is retained by a bearing at the top of the outer, so the force of the spring is being exerted on the repair. I use a metal pin in each position, not being bothered about changing the collapsible characteristics after all these years, you do this drilling and pinning at your own risk! Note that the two halves of the shaft will fit together in two positions 180 degrees out. Oddly both my rack and column shafts have notches for the UJ bolts rather than one shaft having a notch and the other a groove all the way round, so my column and rack shafts will only connect in one position, which means if I reassemble the column shaft 180 degrees out the indicator cancelling cam will end up in the wrong position (as it would if you had a shaft with a groove, match-marked it, and reassembled to that). No big deal as it is only a friction fit on the shaft and can be slid round, but nicer to get things correct in the first place.
Leave that to set a bit and start tidying up the wiring, which basically consists of putting bullets back on the ends of the original brown wires in the harness and ignition switch tail. However as I have no less than four additional circuits that need to connect back to this brown, rather than have a veritable daisy-chain of bullet connectors I splice three of them together with one bullet (two have in-line fuses close by and the third connects to a relay with a spade also close by, so easy enough to isolate each of them for diagnostics) and use the fourth hole for the alarm wire as that goes across the car to the alarm unit in a mini-harness. Turn the power back on and check everything electrical still works, even though the switches are still dangling, and the horn button is removed with the wheel. It's while doing this I discover a thick washer on the carpet, same size as the three that are still on the upper bolts - wonder where that came from...
I then start thinking about the pesky bottom spring and circlip. As I said it is pretty hefty, and just with hand pressure I can't get it compressed far enough to get the circlip on - nowhere near. I'm thinking I'm going to have to lever it down with something, but it will have to be pretty thin as there is going to be very little room to fit the circlip in its slot. I find some flanged plates about 8" by 2" from my BT days some 30 years ago (!) which may be strong enough. I cut a hole in this plate, which just fits over the end of the part of the shaft the circlip fits into, which is narrower than the part that the spring and a washer fits over. As I've only got two hands I stand the steering wheel end of the column on a suitable block of wood, put one end of my plate under the edge of my bench, and press down on the other end of the plate with a hand. It's compressing OK, but the problem is the washer is catching on the shoulder of the shaft, and as I'm levering rather than a straight press it is proving impossible to keep this washer aligned with the larger diameter it is supposed to go over while I'm levering. Go and gaze at my various bits again, and see an old box plug spanner which looks interesting. I'm amazed to discover this just fits over the narrower part of the shaft, and also just fits inside the washer and spring, so perfect for aligning the washer with the thicker part of the shaft! So now I put the box plug spanner through my plate, put the washer and spring on the end of the box plug spanner, and slide that lot over the end of the shaft. Now levering on the plate pushes everything over the larger diameter, and I remove the box plug spanner to reveal the circlip slot - so far so good. However it's still a bit of a fiddle picking up and manoeuvring the circlip one-handed while pressing down on my lever with the other, so I devise a system of string and a tommy bar (from the same plug spanner!) to pull the plate back and compress the spring while the column is clamped in the vice, and I have two hands to fit the circlip. Easy-peasy? - er no. Of course I have forgotten that the circlip is now trapping the plate! But filing the hole in the plate out to a 'keyhole' shape slightly larger than the circlip, but still smaller most of the way round than the washer, I can now fit the circlip into its slot, and lift the plate off over it. Feel thoroughly pleased with my ingenuity, and life-long policy of never throwing anything away - "If you haven't found a use for something yet, you haven't kept it long enough". In fact I have had a major clear out of the garage recently as we are planning to move house this year, but obviously kept enough of the right bits! Finally reattach the plastic cover over the mesh section of the outer, taping it up with masking tape while the adhesive dries.
And now for the refitting and alignment! There is a small ring welded to the outer tube, which the loose plate butts up against, so I wondered if it should be attached to that, although there was no sign it had been. However that puts the plate about 1/2" away from the toe-board which obviously isn't right. And with this column unlike earlier types the inner is fixed in the outer and cannot move up and down, only rotate, so the whole column has to be able to move up and down to get the right distance from the rack shaft so the UJ bolts will fit through the cut-outs in the shafts. Although some have said this bottom plate is part of the alignment, pushing the bottom of the column into the correct position, I've come to the conclusion it is nothing more than a body seal against water, noise and fumes. Two people have confirmed that theirs is also loose and detachable (making it odd that Moss Europe at least show it as part of the column), and another has said the same and that he has a rubber bush, that slides onto the lower part of the column outer, and makes a snug fit to the hole in the plate.
August 2016: That makes more sense, and Moss Europe have a closeup of this plate and the rubber seal, where part of the seal pushes through the hole in the plate. However they show the seal having been slid onto the column first, then the plate. As there are bolts that go through the plate, seal and toe-board one would expect the seal to be sandwiched between the plate and the toe-board, i.e. the plate pushed on first, and the seal after it. When the column and rack-shaft have been correctly aligned over-size holes in the plate and/or toe-board should allow bolts to be pushed through and tightened to provide clamping, but not alignment. In practical terms it was easier to loosely bolt the plate and seal to the toe-board first, then push the end of the column through the hole, rather than slide the plate and seal onto the column, put it in position with at least one upper bolt, then try and get the plate bolts in - the top one in particular is a real fiddle but all are more difficult that way. Now the seal and plate are positioned laterally and vertically by the column, and when the plate bolts are tightened it compresses the rubber such that it expands sideways and seals to the column shaft, as well as being bolted down to the toe-board, to prevent the ingress of water.
Another thing concerns the alignment gauges. The book says to remove the rack, even when it is the column that is being refitted. You do have to remove the rack later on, but there is no point doing it now only to have to refit it, then remove and refit it a second time later on. If using the Moss gauges these have two tapped holes depending on which rack and column they are used for. Compare the gauge to the UJ, position the tip in line with the centre of the UJ, and see which hole in the gauge lines up with the clamp bolt hole in the UJ, and put the clamp screws in those holes. Note that each part of the Moss gauge seems to be a couple of milli-metres shorter than the rubber bumper UJ (not so the chrome bumper), so bear this in mind when doing the alignment i.e. leave a couple of mil between the points or you may not be able to get both UJ clamp bolts in right at the end (alternatively, fit the UJ first, nip up the column bolts to get the correct in and out adjustment, then pull the rack forwards to replace the UJ with the gauges and note the gap between the tips, if any. When you have corrected the column and rack shimming for horizontal and vertical alignment make sure you end up with that same in and out gap). Apart from that when refitting a column it's easier to fit the alignment gauges first, minus the screw in the column piece. Then fit the column loosely, the alignment gauge easily goes through the toe-board plate and seal, and then fit the screw to the column half of the gauge. This is a bit fiddly being recessed into the toe-board 'cup' as it is but can be done. It would be easier with a knurled bolt, or even a hex bolt, or if the screw could be pushed in to the hole a little way before the threads started. Note that the screws must screw into the bottom of the cut-out in the shafts, not onto the splined portion. My Haynes is completely wrong here, by saying the rack and column should be fitted before installing the alignment gauges. This simply cannot be done, the two have to be moved apart a couple of inches to get the gauges onto the shaft, and off again to refit the UJ. With the gauges on adjust the column position and the shims as above to get the correct alignment. However my Leyland Workshop Manual also has a major error, in that it tells you "Slacken the screw on the column point gauge and slide the gauge down until the points of both gauges are on the same plane but not overlapping". The whole point of the gauge screws with this column is that they must screw into the cut-outs in the shafts, and the whole column must be slid up and down to get the correct in and out position. Unless you do this it is highly likely that you will not be able to get the second UJ clamping bolt inserted, the cut-out in the shaft not lining up with the hole in the UJ. This isn't the case with earlier columns, where the whole inner shaft is free to slide up and down inside the outer, with those the shaft will automatically take up the correct position. I repeat, with this later energy-absorbing column you can only adjust the in and out position of the inner, and hence get the cut-out in the correct place for the UJ, by moving the whole column on its upper bolts (which is also why the toe-plate must be able to slide up and down on the column outer).
Additionally at the end of the process i.e. with the gauges replaced by the UJ, it tells you tighten the two upper bolts, then measure the gap at the third bolt, and fit shims accordingly. This makes no sense to me, as the gauge of the correct size would have to be gripped by almost the same tension as the final shims which is 12-17 ft lb as you were sliding it in and out. Better to align, fitting shims as required to the third bolt and tightening all three to get the correct alignment while the gauges are still on the shafts. More long-winded certainly, but it seems more accurate to me. The two upper column bolts do not allow the column to 'rock' on them when tightened, so unless the shimming required on the third bolt is negligible to nothing then there must be some sideways pressure on the UJ and hence the rack pinion bearing. If you shim the column to that final position, then the two shafts will not be accurately aligned. When the column and rack shafts are correctly aligned with the gauges, only then pull the rack forwards to remove the gauges, fit the UJ, and refit the rack. Unlike the column, the rack (with any shims) should always go back in the same position. Whereas if you are only fitting shims to the third column bolt and fully tightening that after the UJ is installed, you could be affecting the vertical alignment, and indeed would have to lever the bottom of the column downwards in order to get the shims inserted. This is why it makes more sense to fit the gauges before installing the column, leaving the rack where it is until the very end of the process, only then pulling the rack forwards to remove the gauges and refit the UJ. Note that if you raise the front wheels off the ground you only have to remove the four rack bolts, leaving the track-rod ends attached to the steering arms. As you pull the rack forwards a few inches to allow you to remove the gauges and fit the UJ, the wheels will simply go 'pigeon-toed' i.e. turn in towards each other.
Refit rack bolts, tighten UJ clamp bolts, refit switches. Check all the electrics again, which involves putting the key in the ignition, and immediately sense that it is now closer to the bottom of the dashboard than it was before. I now realise what that odd thick washer was - it must have been between the column and body brackets on the right-hand bolt which would space that side down a bit - buggah! To fit it now would involve realigning the column. Consult the workshop manual to find something I missed before, that there should be such a spacer on all three upper column bolts! Indeed six shown in the Leyland Parts Catalogue, but only three in online parts lists. However the manual talks in terms of "if the packing washers are mislaid" so it is probably no big deal, and I can live with it until I next have to remove rack or column. Refit the column cowls before the steering wheel as it is easier, and if the lower cowl screws (covered by the edge of the dashboard) were fitted before don't bother refitting them, they just aren't needed. If you haven't upset the positioning of the indicator cancelling cam, and it was correct to begin with (cam pointing at the switch when straight-ahead), then loosely refit the steering wheel to turn the shaft to the straight-ahead position, then refit the wheel fully. Otherwise fit it with the nut not fully tightened, take it to a quiet straight road close by (not 10 miles away!), and adjust as required. Take your socket etc. with you so as to fully tighten it before driving back, so you can take the scenic route and enjoy getting your car back on the road again. The rattle-free steering really is an improvement.
Steering Racks July 2019
Just a snippet of info as I've seen people asking how to tell the difference between CB and RB a couple of times.
Lubrication: The oil to be used is the same as in the rear axle. Early racks had what looked like a grease nipple in the upper part of the pinion housing, but this was for oil not grease - 'ten strokes of the oil gun but no more' according the Workshop Manual. The capacity is shown as 1/3rd Imperial pint, 0.19 litre, 0.39 US pint. Put too much in and you can burst a gaiter, so if none leaks out between service intervals you wouldn't want to keep pumping more in. However 'old' racks don't seem to be able to keep their oil, changing gaiters on both mine at various times I refilled and it spent the next several months dripping out again, and others have said the same. 'Empty' when I removed the gaiters, but the innards were liberally coated with oil, so I don't think it matters much as long as you keep an eye on the condition of the gaiters.
Without the oiler some talk about removing the damper cover from the pinion, but you would have to remove at least the damper and spring, or the yoke, in order to get oil in while air was coming out. Personally I've done it past the gaiter, and again there are differing opinions. It makes sense to push the nozzle of an oil can through the small end of the gaiter i.e. past the track-rod, but when I fitted new gaiters it seemed a bit tight to me and I didn't want to risk ripping it. So I used the small end, going it at the top, and cupping my thumb and fore-finger round underneath that part of the gaiter to stop it coming out again. With the requisite amount in and the tie fitted work the rack back and fore from lock to lock sloooowly to distribute the oil without bursting a gaiter or forcing it off the tube.
For some time replacement racks have been supplied 'grease filled', so no further lubrication should be necessary, and nothing should leak out.
There is a yoke aligning the rack laterally to the pinion with a small clearance, with two different methods of damping any movement within that clearance, and two methods of setting the adjustment of the clearance. Originally there was a damper and a spring inside the yoke. The cover presses down on the yoke, the yoke on the spring, the spring on the damper and the damper on the rack, and the clearance is set by shims between the cover and the body. This clearance is effectively between the rack and the yoke and is set by fitting the cover and gasket without any shims, and tightening the bolts until the rack can just be pulled back and fore through the tube. The gap between cover and body is measured, and shims to this value plus 0.5 to 3 thou fitted.
In the first cost-reduced version there is no damper. The spring sits inside the yoke, the cover presses down on the spring, the spring on the yoke and the yoke on the rack. The clearance is again set by shims as previously and now is between the yoke and the cover.
In the current version of some newly-produced racks (e.g. Moss for the MGC), and reconditioned racks for the MGB from other sources, the clearance is set by grub-screw and lock-nut in place of the usual shims. Probably easier, quicker and hence cheaper than trial fitting, measuring, removal and fitting the required shims. To obtain the same clearance as before the screw would have to be tightened until the rack just started to bind, then be backed off. The amount to be backed-off would depend on the pitch of the thread, which if it were (and I'm guessing here) a 5/16" UNF is 1.058mm or 41.65 thou, and for 3 thou is about 25 degrees, or only 7% of a turn between too tight and too loose! To my mind that needs more care than using feeler gauges and taking shims out of a box, but what do I know?
As a case in point one newly reconditioned unit had about 6mm of play between rack and pinion as supplied. On slackening the lock-nut the grub-screw could be turned with fingers, so something very wrong. On removing the cover the spring was in the recess in the top of the yoke which is fair enough. There should have been a washer on top of the spring so the end of the screw could bear down on it and compress the spring and hence position the yoke, but it was underneath. The yoke was free to move up and down, allowing the rack to move right away from the pinion and give masses of free-play in the steering. Refitting the washer with the rack installed and the housing at an angle is tricky as the washer could slip off the spring while fitting the cover. I suggested that if the spring protruded from the housing with the yoke pressing the rack against the pinion, then the screw could be removed and a rod fitted through the hole in the cover, the washer and the spring. Then when the cover was screwed down the spring would be under compresion, holding the washer up against the cover, the rod could be withdrawn and the screw fitted. If the spring didn't protrude I think the best thing would be to glue the washer to it.
The other adjustment is where the tie rods come off the ends of the rack. These are ball joints which articulate, with a sprung seat for the inner ball. The ball housing which fits over the outer ball is set such that the tie-rod needs a force of 32 to 52 pound INCHES to cause articulation. This could be measured with a spring-balance 10" out from the joint with a force of 4lb ... or a couple of kilo bags of sugar! The lock-nut is screwed up to the ball housing and has areas that are staked into grooves in the housing and the rack to lock the housing in position. These threads are rather fine, and easy to cross-thread, for example if the housing and tie-rod are removed to replace the passenger side rack support bearing or bush.
According to Clausager four different types of column and wheel hub splines were used over the years, and are not interchangeable. See here for the various change points.
As far as the wheels themselves go the first had wire spokes in three groups. For 1970 it changed to three flat spokes with five holes each, inside a steel rim, padded with dense foam, with a faux-leather covering. In 1973 the five holes (said to have trapped fingers!) were replaced by a tapered slot, but only until June 73 when the slot became simply a depression in each solid spoke, as the slots were found to trap dangly bracelets! For 1977 to the end a wheel with four plastic spokes was used, except for the North American LE of 79-80 which oddly went back to spokes with holes in again, albeit only three in a smaller diameter wheel. It seems likely that wire, original alloy with holes, alloy with slots and alloy with depressions, and finally plastic and American LE have the four different splines.
The wheel is fitted to the shaft with a splined and tapered joint and a nut (about 1 1/16" or 3/4" Whitworth on my 73 roadster and 75 V8), which together means that even if the nut comes loose the wheel should not be loose on the column, the taper must be 'broken' as well.
I've seen pullers recommended, a 2-leg works on the slotted wheel, possibly the earlier version with the holes, less so if at all - avoiding damage - on other wheels. Short of that the best way is as follows:
I've seen it claimed that this method can cause the collapsible shaft to collapse. But as far as the upper shaft of the rubber bumper (earlier for North America and applicable to all V8s) full energy-absorbing column goes, there is a top bearing that retains the upper half of the shaft in the outer, which prevents it going any further into the column, and in any case bracing the knees behind the wheel is going to counteract any downward movement, the shock of the blow releasing the taper. It's possible it could happen on the earlier collapsible column as the whole shaft is free to slide up and down in the outer, so there is an alternative method. This involves slackening the nut as before, then alternately pulling one side of the rim towards you and pushing the other side away from you, with force, as if you were trying to buckle the wheel, and repeatedly reversing. This method didn't work for me the first time I took the wheel off Bee or Vee, but it has on subsequent occasions.
November 2019: Just come across this John Twist YouTube that describes this process with just a couple of minor differences dated 2007 ... however this section has been here since February 2000, and I almost certainly had Bee's wheel off this way in 1990. Just saying.
Update August 2011:
1977 (and later) model-year cars have a special wheel boss which engages with a cancellation collar on the indicator/turn switch, see here. A non-standard wheel is likely to fail to cancel the indicators without a modification as indicated.
Steering wheel alignment January 2017 The steering wheel should very obviously be 'straight' when travelling in a straight line, and not turned to one side, and there are several ways of achieving this. There is a second aspect to this, and that is indicator cancelling. On pre-1977 cars this is done by a peg or cam attached to the steering column, which with the car travelling in a straight line should be between the cancelling fingers of the indicator switch, to get balanced cancelling each side. If it's unbalanced one side may not cancel unless the wheel has been turned more than would be normal for a typical turning. There is a third aspect on cars with a steering lock, and that is how far you have to turn the wheel from straight ahead to get the lock to engage. If you habitually make sure the lock engages you could have to turn the wheel up to 180 degrees to do so, so if you need to remove the column or rack for any other reason it might be an opportunity to correct the steering lock, reinstall the UJ appropriately, and then correct the cancelling cam (which is used on all locking columns) and steering wheel.
The first aspect can obviously be corrected by positioning the wheel on the column splines appropriately. However on Mk1 cars indicator cancelling is done by a peg screwed into the column i.e. the column should be in a specific position relative to the switch when travelling in a straight line. If it's the column that has become misaligned then simply moving the wheel will leave indicator cancelling incorrectly set even if you correct the wheel position. On those columns you are left with altering the position of the column UJ on it's respective shafts to correct the column, and hence the wheel. Mk2 cars up to 1976 have a cam that can be slid round the column into the correct position for the indicator switch. So on these cars a combination of sliding the cam round and moving the wheel will correct both problems. On 1977 and later cars with the four-spoke steering wheel the cancelling mechanism is part of the wheel itself, so moving the wheel will correct both aspects.
On cars without the full energy-absorbing column the column shaft has a notch for the UJ clamp bolt, meaning that the UJ can only fit to the column in one position. But the rack shaft has a groove all the way round, so this has to be used to correct column and steering wheel alignment on Mk1 cars. It can also be used on some later models, but on my V8, and possibly all RB cars, both column and rack shafts only have the notch, meaning the two shafts and the UJ can only be assembled in one orientation. However these cars have the sliding cam that can be used to correct the indicator cancelling position, so that and the steering wheel can be moved on the column shaft to correct the alignment.
I say 'correct' but none of the above can correct alignment to anything finer than one spline, so you could end up with a choice of having the wheel offset one way, or the other, but not dead-centre. However fine adjustment can be done at the track-rod ends. Do this by finding an area big enough to roll the car forwards in a dead straight line - going by the direction of the car and not by the angle of the steering wheel. This will leave the wheel off-centre, and we can adjust the track-rods until the wheel itself is central. For example, if the steering wheel is slightly turned to the right when travelling in a straight line, i.e. the road wheels would be turned to the left to get the steering wheel central, then we need to move the road wheels to the right to get both them and the steering wheel in the straight-ahead position. To do this unscrew the off-side track-rod from its track-rod end to push that wheel out to the right, and screw the near-side track-rod into its track-rod end by exactly the same amount to pull that wheel in. If the steering wheel is turned to the left when the car is travelling in a straight line then the process is reversed i.e. unscrew the near-side track-rod and screw in the off-side track-rod. Go by whole turns to start with, then half and quarter turns, a paint spot on each track-rod will help you keep track ... so to speak! Alternatively if you go to a decent wheel alignment place that does four-wheel tracking they will get the car pointing more or less straight, then turn the steering wheel to straight ahead and clamp it there, then adjust each track-rod to get half the overall toe-in on each wheel. However that may upset the indicator cancelling!
Another aspect of steering geometry is that strictly speaking you should have the same number of turns from straight ahead to each lock, so the turning circle size is the same in both directions. If one wheel turns in more than the other it could rub on something else on full lock. You can correct this in the same way. Determine any off-set by rotating the steering wheel fully one way and note the angle of the central spoke to the vertical, then rotate it fully the other way and again note the angle. Or you can put tape at the top of the rim when the wheel is pointing straight ahead, and note how far that is off the vertical on each lock. Ideally the angle should be the same on both locks. If it is different you can correct it by offsetting the wheel on the column so that the number of turns to each lock is the same at the steering wheel, i.e. with the wheel in the straight-ahead position the road wheels will be offset to one side or the other. Then use the above process i.e. position the road wheels so that the car would travel in a straight line and the steering wheel is offset, then adjust the track-rods to correct the steering wheel. However this would be quite a bit more complicated with the early columns with the screwed-in indicator cancelling peg, as the steering wheel would have to be offset by moving the UJ on the rack shaft, rather than moving the steering wheel on the column shaft.