by Herb Adler 5243 3409


I had just found out that the case hardening of the spider gears, in the differential, and their axle was shot.

Well....take it to a diff specialist to have the holes bored out and an oversized axle fitted. HA HA.

Can't do. To bore out the inside of the spider gears would require them to be annealed, then bored then case hardened again, around $200 each plus another $200 for the axle, plus labour. They recommended that it is cheaper to replace these items. OK go ahead. After two weeks they still can't source parts. After three phone calls I had two sources, including the guy I bought it from, so got the bits free. Two weeks later the diff eventually comes home. Now to install it. Unfortunately it still weighs 300kg and I can't lift and wriggle it into place past the battery boxes. Bugger! Now I need to drop the rear axle assembly by unbolting the fronts of the springs and disconnecting the shock absorber links. More work. Eventually get the diff back in, the rear axles are easy to fit and soon the wheels are back on, and on the ground.

Trying to get it to run, again –Fuel Pump revisited

Now back to the engine and try to get it running and tuned. Turn on the ignition and am rewarded by the steady ticking of the fuel pump. The steady ticking of the fuel pump. The steady ticking of the fuel pump. More swearing. What's wrong now? Turns out to be no suction on the pump inlet. Jack up the back of the car, take off the wheel (remember I've just put it back on!) and whip out the pump. No suction and no pressure, checked by alternately blocking the inlet and outlet, which should cause the pump to stall. Get out the workshop manual and pore over the pump details. OK there's this chamber thingy that is on the inlet side. Lets check its gasket. Off with the single bolt and the cap. There's a cork gasket in there that has seen better days. I don't have any cork gasket material, but I do have paper gasket sheet. So.. I cut out a new paper gasket and fit it, replace the cap and bolt and wonder of wonders I now have suction, but still no pressure. Back to the manual and there's another chamber, with some sort of diaphragm in it. Its the output pressure filter, to remove some of the fuel pulsing. Take it apart and reseal the diaphragm, fit a new O ring and reassemble. Also dismantle the valves and replace the valve sealing washers. Connect to the electrics and try again. I now have pressure. Whooppee! Errr ... why doesn't it start after being stalled? The neighbours ears are burning again. This time I head for my electronics bench, where I have lots of electrical type tools and instruments. Connect the pump to the bench supply and check its operation again. Still won't reliably start after stalling. Dismantle the solenoid from the pump body and give the diaphragm a turn so that the contacts toggle. Reassemble and try again. Not any different. Now I know that there's an electronic module around that replaces the whole mechanical mess. Fire up the computer and start searching on the internet ( a fantastic resource ) and find the module in the most obvious place – SU's web site. 40 quid (~$80), plus postage and who knows how long a delay. Keep looking and hope to find an Australian dealer. I didn't do any good on this, but I did find a modification that uses a transistor to massively reduce the current through the contacts, on the Queensland MG Club's web site. Hey, I've got all those bits in the junk box. Bob's your uncle and I've done the mod., pump runs well, stops and starts as it should. I decide to let it tick on the bench for a while to make sure everything is OK. After an hour or so the pump is quite warm but still ticking. Now to stall it. Bugger it won't start, again. I've had it. Go to Concourse Spares and buy an ECCO pump, $129. Its a direct replacement for the SU.

Install it, connect fuel lines and electrics and switch on. Pump does its thing, crank the engine and after a bit the engine fires and runs, and runs and runs. Beauty now to set the timing and tune the carbys.

The Carbys’ Turn

Syncing the throttles was easy with an air flow meter. Now to set the mixture. Run out of adjustment towards the lean end of the jet screw. I know that there are #5 needles in the carbs instead of FXs as specified in the book. The #5s are the rich version of the FX. So I need new needles. Off to the local carby specialists, young guy on the counter says they’ve got some, disappears and shortly returns with two needles. I double check and can make out FX on one of them, couldn’t see anything on the other (not unusual as I’m half blind in one eye and can’t see properly out of the other ). Get home and strip the carbys, extract the needles and decide to triple check the new needles before fitting and tuning, as I don’t want to fall into the trap of putting the wrong needles in thinking they are correct. Using a magnifying glass I can definitely see that one needle is marked FX, on the other, however, I can barely make out a D, obviously not an FX. To make matters worse both needles have cross hatch score marks along them. Go and check against the #5s I have, which turn out to be quite smooth. Alarm bells, has someone tried reprofiling these needles? To be sure I download the needle profile specs for both the FX and #5 needles, plus a needle profile measurement chart. After hours of labouriously measuring all three needles at the measuring stations I came to the conclusion that the so called FX and the D had been “sanded” down or reprofiled, as they were off the specs by a couple of thou. I measured the #5 to be sure that my measuring technique wasn’t to blame for the errors. My measurements came to within half a thou of spec, so my measurements were accurate enough.

Back to the carby specialists with my measurements and explained the issue. They happily took back the needles and ordered new FX ones, which arrived several days later, and were correct. Fit the new needles and try to tune the carbys once again. Still run out of adjustment at the lean end. OK I must find out where the true fuel level in the float chamber is meant to be, the turn upside down and the gap should be XX is not much help since I found values of XX from 1/8” to 7/16”. Well back onto the SU web site and submit a query, basically along the lines of I have HS4 carbys with replacement plastic floats and need to know an absolute fuel level. After two weeks I get the reply “Plastic floats are not adjustable”. Derrr……. I know that. Sent email back saying I know that; but the fuel level IS adjustable by using thicker or thinner washers under the needle valve assembly. Several days later I got the reply that the fuel should be set at 3/8” below the bridge in the carby. Hurray some useful advice. I eventually got the levels set correctly ( turns out to be the 7/16” gap).

Now to start the engine and setup those carbys. Still running rich, a bit of a head scratch, when further action is taken out of my hands – the damn thing runs out of petrol! Go find a wall to bang my head against to make it feel better. This was on the last weekend in June, so there it stands, for now.


Whilst all the above was going on I had a bit of spare time, between renovating units, social gatherings and other family obligations, to do some work on the B_B, so the following is not in chronological order.


This car is going to be a road car, for pure driving pleasure, not one to be dusted off every so often to show it off, ergo to hell with concourse standard, I am going to improve it for better driver operation and enjoyment.

Firstus:- Engine Oilus.

After the debacle with the oil filter and the obviously messy process of changing it I purchased a spin on kit and fitted it. The only difficulty in this was bending over the locking tab, once the kit was installed on the engine, practically impossible to get at, however, filter changes will be a breeze.


Fitting a radio and accessories.

Steering column, indicator switch and relay driven lights

Electric windscreen washers

Hood frame, vinyl trim and other woes

All the things I haven’t yet got around to or discovered