1. Remove the front floor covering from inside the car.
2. Remove the through-bolt securing the steering column upper support bracket at the parcel shelf. Mark the position of the clamp on the column outer tube to facilitate alignment on reassembly. On later models a shear-bolt is used at the upper support bracket and a saw cut will have to be made in the bolt to enable it to be removed using a screwdriver. The right-hand cowl will first have to be removed from the column to gain access to the bolt.
3. Remove the pinch bolt securing the lower end of the steering column to the steering unit pinion shaft, then pull the column assembly upwards to disengage it from the pinion shaft.
4. Still inside the car, remove the four self-locking nuts securing the rack 'U' bolts to the toe-board.
5. Inside the engine compartment, remove the air cleaner assembly from the carburettor. Also disconnect the exhaust pipe from the exhaust manifold.
6. Disconnect the engine steady rod from the cylinder block and move the rod out of the way. On later models, note that the engine earth strap is also secured by the steady rod bolt.
7. Remove the two bolts securing the sub-frame towers to the body crossmember at the engine compartment bulkhead.
8. Jack up the front of the car and support on stands positioned under the edge of the floor panel at the front jacking points. Use wooden blocks between the stands and the floor panel. Remove both front wheels.
9. On models with 'dry' suspension, disconnect the shock absorbers from the mounting pins on the suspension upper arms.
10. Disconnect both track rod ends from their respective steering arms, using a suitable joint separator tool.
11. Disconnect the exhaust pipe from the support bracket on the final drive unit housing.
12. On models with remote-control gearchange, detach the gearchange extension housing rear mounting from the floor panel. On later models with the single-rod type remote change, remove the through-bolt securing the gearchange housing to its mounting bracket and free the housing from the bracket. It may be necessary to lever the housing over to enable the through-bolt to be removed.
13. Support the sub-frame with a jack and wooden batten positioned across the car so that it locates on the underside of the sub-frame at the lower suspension arm pivot points.
14. Slacken, but do not remove, the centre-bolts securing the sub-frame front mountings to the body. These are accessible through the apertures in the front panel below the bumper.
15. Remove the four bolts and nuts securing the subframe rear mountings.
16. Release the jack under the sub-frame and allow the rear of the sub-frame to drop until a gap of about 3/4 in (20 mm) is present between the top of the sub-frame turrets and the valance aperture ('A'in illustration). Use a wedge if required, to force the sub-frame downwards to obtain sufficient clearance.
17. Extract the 'U' bolts and plastic anti-friction strips (when fitted) from between the steering unit housing and the sub-frame.
18. Move the rack downwards and turn it to bring the pinion vertical to clear the aperture. Carefully manoeuvre the unit out from between the sub-frame and the body on the driver's side. Note the sealing ring fitted at the pinion housing on the unit.
Installation Install the steering unit in the reverse order of removing, but pay special attention to the following points:
a) Ensure that the sealing ring is in position at the pinion housing before installing the steering unit.
b) Where fitted, use new plastic anti-friction strips at the 'U' bolts, if required.
c) When installing the rack, initially tighten the rack 'U' bolts only lightly so that the pinion can be aligned with the column assembly.
d) On Mk I models, position the steering column assembly in the car and engage the split portion of the column clamp with the marked spline on the steering unit pinion shaft. Push the assembly down onto the pinion shaft until the pinch bolt can be easily inserted. On RHD models, the clamp must be positioned with the bolt axis below the column and parallel to the rack axis . On LHD models, the bolt axis must be above the column at an angle of 160 to the rack housing. Tighten the pinch bolt.
e) On later models, set, the steering gear in the straight ahead position with the locator pin .
Remove the rubber grommet from the floor panel on the opposite side to the steering column, then remove the plastic plug from the rack housing and insert a 1/4 in (6 mm) dowel or drill shank into the hole. Traverse the rack slowly until the pin engages fully in the rack shaft to lock the steering in the central position. Position the column assembly in the car, with the steering wheel spokes positioned symmetrically, and engage the column clamp on the pinion shaft splines.
Remove the centralising pin and turn the steering from lock to lock. Now push the column assembly down onto the shaft until the pinch bolt can be easily inserted, then tighten the pinch bolt. Refit the plug in the rack housing and the grommet in the floor panel.
f) With the rack 'U' bolts still slack, offer up the column upper support clip to the clamp plate at the parcel shelf. The clip should be able to engage the clamp plate without any sideways strain to align the two. Should any sideways strain be necessary, slacken the screws securing the clamp plate to the parcel shelf, align the clip into the clamp plate and fit the through-bolt. Where a shear-bolt was fitted, use a new shear-bolt. Retighten the clamp plate to parcel shelf screws, then tighten the column clip bolt. On models with the shear-bolt, tighten the bolt until the head of the bolt shears off.
g) Tighten the rack 'U' bolts progressively a half-turn at a time until secure. Ensure that the thread on each 'U' bolt protrudes equally through each nut.
h) When installation is completed, have the front wheel toe setting checked as detailed previously.
Adjustment Two adjustments of the steering gear are possible; the rack support yoke clearance adjustment, and the pinion bearing pre-load adjustment. Both these adjustments are effected by varying the thickness of a shim pack under a cover plate. The steering gear must be removed from the car to carry out either of these adjustments.
Accurate measurement is essential to ensure correct adjustment of the unit, and it is therefore recommended that this be left to a specialist or other suitably experienced personnel as the adjustment can have great bearing on the life and efficiency (and safety) of the unit.
Overhaul In most cases of wear or damage to the steering unit, it will probably be more economical and convenient to exchange the complete assembly for a new or reconditioned unit rather than attempt to repair it.
The most common points of wear are at the rack support bush, the gear teeth on the rack and pinion, the pinion shaft bearings and the track rod ball joints at the ends of the rack.
Wear at the rack bush, at the opposite end of the rack housing from the pinion, will allow excessive movement of the rack at that end. Damaged or worn gear teeth on the rack or pinion will make the steering noisy or stiff in use. Excessive side movement at the pinion shaft indicates worn bearings. If either of the track rods fails to stay in any set position, this is a sure sign that the rack end ball joints are worn.
If the track rods are difficult to move or are noisy when moved, this indicates damage caused through lack of lubricant in the rack.