Energy-absorbing Steering Column

The loose plate at the bottom of the column, shown as part of the assembly in parts lists. The rubber seal is more or less the same size and shape but is separately quoted. Other people have a rubber sleeve that fits over the end of the column outer, inside the flange.

The lower bush, plastic 'washer', spring, steel washer, and circlip that secure the bottom half of the shaft into the column, the sheared 'pins' having allowed the lower part of the shaft to be pushed out of the column.

The plastic sleeve over the collapsible 'mesh' part of the column.

Stubs of plastic shear 'pin' remaining in the holes of the outer/lower part of the shaft ...

... removed

Location of ignition switch securing screw (arrowed)

Screw slackened and switch removed

Inner circlip (A) retaining my bearing in the housing (BHH1596), and outer circlip (B) retaining the shaft in the bearing. Although removing A allowed the shaft and bearing to move up and down inside the housing I still couldn't withdraw the upper shaft. From John's description this was possibly because the bearing was catching on the pop-rivets.

The (apparently superfluous) circlip behind John's bearing on the new, earlier (BHH1596) column. The circlip on his later (BHH1856) was sitting in front of the bearing (as is mine on an earlier column). As far as he could see the slots are the same on both. John says there is a shoulder on the shaft which should stop the bearing going down too far on the shaft, or the shaft being pulled up through the bearing. So with the bearing sandwiched between the two shoulders and the two circlips, there should be no possibility of the shaft moving relative to the outer, and hence no chance of putting stress on the shear pins. (John Bilham)

The earlier column BHH1596 with the bearing housing having the same OD for all its exposed length, the separate column switches clamp onto this.

The later column BHH1856 with the reduced diameter section for the later one-piece switch assembly to slot onto. (John Bilham)

John's dismantled housing: A shoulder inside the housing positions the bearing, then a shim, and finally the large circlip to secure the bearing to the housing. The bearing is interesting - it is rubber-coated, except for a small section which is copper (arrowed). Speculation is that is to provide an earth from the column outer (bolted to the body) to the upper part of the shaft, as the injected plastic shear may prevent an adequate electrical connection to the lower shaft (which should have an earth via the UJ, rack and crossmember and chassis rails). However this is the 77 and later column, with the horn button on a stalk which sends 12v to the horns, so a column earth is not required. It is required on the earlier rubber bumper column, but I and others have had problems getting a satisfactory earth to the horn button, so if there it doesn't work very well. (John Bilham)

Remains of the injection moulded plastic in the upper half of the shaft ...

... and the 'waisted' section it sits in.

Repaired shaft

The 'steps' in the shaft, the washer kept getting caught on the bigger one when I tried compressing the spring.

Box plug spanner neatly fits over the narrowest part of the shaft, and inside the spring and washer, so nullifying the effect of the first, large, step. The smaller step wasn't a problem.

'Keyhole' in plate cut to be slightly bigger than the circlip ...

... but still smaller than the washer it has to press against.

String wound up by a tommy-bar (from the same box plug spanner!) to pull on the plate and compress the spring ...

... the box plug spanner can then be removed ...

... and the circlip fitted!

Plate (A), seal (B) and alignment gauge attached to column before refitting. Subsequently I chose to attach the plate and seal to the toe-board first, then push the alignment gauge (screw removed) on the end of the shaft through them.

Moss Europe showing the plate (A) below the seal (B), which would mean the bolts tightening onto the rubber seal. It should be the other way round, to sandwich the seal between the plate and the toe-board. B2 is the portion of the seal that protrudes through the plate. Moss show the seal and plate separately here as item 33 (seal: CB AHA8270, RB BHH1856RBR (NCA) and plate BHH1856BKT)

Column aligned.

Align the tip of the gauge with the centre of the joint, then the hole in the gauge that lines up with the clamp bolt hole is the one to use.

Measurement several times and as careful as I can has shown that the each half of the gauge is a couple of mm shorter from screw to tip than the UJ is from bolt to spider centre, making about 5mm for the two. An orange pencil in the UJ bolt hole is lined up with the gauge screw ...

... but the tip is short of the centre of the spider, shown by the concentric rings. This is slightly concerning as this column shaft can't slide up and down inside the outer, the outer has to be bolted to the body brackets to give the correct distance between the cut-outs in the two shafts. In the event, I can get the clamp bolts in the UJ and the rack bolts back into the cross-member brackets, so all was well.

Note the column shaft has a notch for the UJ clamp bolt meaning the UJ can be attached to it in only one rotational position ...

... and the rack shaft is the same! This means that you can only correct steering wheel alignment by a combination of the position of the wheel on the shaft and the relative positions of the track-rod ends on the track-rods. By comparison the roadster rack shaft is grooved all the way round, meaning that the nearest rack/UJ spline can be used to correct steering wheel alignment as well as the others.