FIG 9:1 Components of the steering gearbox, with assembled view top left
9:3 Servicing steering wheel and column
9:4 Removing and installing steering gear
9:5 Servicing steering gearbox
9:6 Removing and installing tie-rods
9:7 Removing and installing steering damper
9:8 Wheel alignment and toe-in
The layout of the steering gear can be seen in FIG 8:1, making due allowance for the fact that the illustration shows the front axle of a lefthand drive car. The components of the steering gearbox are shown in FIG 9:1.
Worm 23 is carried on ballbearings in the box 15, its splined end being connected to a flexible joint which, in turn, is connected to the steering column and steering wheel. Rocker shaft 7 runs in bushes in the box and carries a peg on its arm and a drop arm 2 on splines at its lower end. The peg engages the worm groove, so that rotation of the worm by the steering wheel causes the peg and arm to move in an arc, the partial rotation of shaft 7 leading to an angular movement of the drop arm. As this arm is connected by tie rods to the steering arms on the stub axles, steering movements are thus transmitted to the front wheels.
A telescopic damper 11 is connected between the drop arm and a clip round the lower axle tube to damp out excessive liveliness in the steering.
Check steering angles and toe-in every 3000 miles and check all nuts, bolts and other fastenings for security every 6000 miles. Particulars of toe-in adjustments will be found in Section 9:8.
Every 1500 miles, grease the kingpins. The method is outlined in Section 8:2 of the Front Suspension chapter. Grease the tie-rod joints every 3000 miles. The rods may be identified in FIG 8:1 of the same chapter. In each case use a multi-purpose, lithium-based grease such as Retinax A.
Every 6000 miles, check the level of lubricant in the steering gearbox. It should come up to the bottom of the filler hole. Top-up, if required, with Hypoid oil SAE.90. The filler plug is readily accessible if the coverplate in the floor of the luggage compartment is removed. It is over the steering gearbox and is secured by four screws.
Removing steering wheel:
1 Disconnect battery. Remove horn button by prising out, or on later models, by turning anticlockwise. Strong pressure on the three lugs on the outer ring will be needed.
2 Remove horn contact pin. Use a socket wrench to remove the steering wheel nut. Draw off steering wheel, taking care of the spring and retaining ring for the column bearing.
Key to Fig 9:1
1 Steering box assembly
2 Drop arm
3 Cover
4 Adjusting screw
5 Locknut
6 Filler plug
7 Rocker shaft
8 Thrust pin
9 Tapered peg and roller bearing
10 Thrust washer
11 Spring
12 Thrust washers
13 Castle nut
14 Oil seal
15 Steering box
16 Dowel
17 Clamp
18 Lockplate
19 Seal
20 Bush
21 Top ballrace
22 Ball cage
23 Steering worm
24 Ball cage
25 Bottom ballrace
26 Spacer
27 Adjusting shims
28 End plate
Installing steering wheel:
Proceed in the reverse order, fitting the spring and retaining ring to the wheel hub and then fitting the wheel with the central spoke pointing downwards. The wheels must be in the straight-ahead position. There must be a lockwasher under the securing nut. Check that flasher switch works correctly.
Removing steering column:
1 Disconnect battery. From floor of front luggage compartment, remove cover over steering gearbox (four screws).
2 The flexible coupling between the steering column and the gearbox is secured by clamping bolts. Release the upper clamp from the column (see FIG 9:3).
3 Slacken steering wheel nut, turn wheel until column disengages from coupling and withdraw wheel and column from outer column tube.
Check steering column. It must not be out-of-true by more than 2mm (.08 inch). Check the bearing in the outer column. This is packed with special grease and no maintenance is required.
Installing steering column:
Use the reverse procedure to dismantling, fitting a new lockplate to the bolt in the coupling clamp. Make sure the coupling is engaged when wheels and steering wheel are correctly aligned.
Removing outer column:
1 Remove steering wheel. Disconnect cables from sockets. Unscrew nuts from mounting below instrument panel.
2 Turn outer column slightly to release it from the rubber mounting.
The top bearing is shown in FIG 9:2. If it needs renewal, remove the inner column as described in the preceding instructions and then push out the bearing from below. Renew rubber mounting if it has deteriorated.
Installing outer column:
Check that inner column turns freely in bearing. Insert the tube so that the steering column projects 23.5 + .50 mm (.925 + .020 inch) above the face of the bearing as shown in the illustration. Connect the cables so that the colours match.
1 Jack up front end of car and remove lefthand front wheel. Disconnect battery.
2 Remove steering gear cover from floor of luggage compartment (four screws).
3 Detach steering damper from drop arm 2 (see FIG 9:1). The damper may be identified in FIG 8:1. Detach tie-rods from drop arm by first removing the nuts. Do not try to drive the taper pins out of the drop arm as they are very tight and the threads will be damaged. Use an extractor of the type shown in use in FIG 9:7.
4 Turn horn button anticlockwise to remove it or prise it out on early models. Remove contact pin. Turn steering fully to the right or the left (lefthand drive or righthand drive cars respectively). Release steering column from steering coupling as described under ’Removing steering column’ in Section 9:3.
5 Release steering gear from axle tube by removing clamp 17 (see FIG 9:1). Pull gear forward to remove.
Installing:
Adopt the reverse order to dismantling. When refitting the gear, make sure the dowel pin is engaged (see FIG 9:5). Use new lockplates under the clamp nuts and tighten them to a torque of 22 lb ft. Check the oil level and top-up if necessary (see Section 9:2). Check and if necessary adjust the toe-in (see Section 9:8). This operation is essential whenever the steering gear is removed and refitted.
Note that it is not considered advisable to dismantle the steering gear except in an emergency. The makers will not recognize any claims under guarantee if the seals on the coverplate are broken. Factory-conditioning is the best way to cure faults in a gearbox, but the following instructions will be found useful if the work must be carried out by the owner.
Dismantling:
1 Remove clamping bolt and pull off flexible coupling. Remove nut 13 (see FIG 9:1). Use a puller or special tool P.72 to pull off the drop arm 2.
2 Remove cover 3 (four bolts). Withdraw rocker shaft 7. Pull off washers and spring 10, 11 and 12.
3 Remove end plate 28 (four screws) and take special care of shims 27. Extract spacer ring 26. Use a soft-faced hammer to drive out worm 23 downwards. Take care not to confuse the locations of the two bearing sets 21 and 22, and 24 and 25. Always refit them exactly as they were removed. If seal 14 is to be renewed, drive it out from inside. Clean the parts and check for wear. Check seal 19 and fit of rocker shaft in bushes 20. Check ballbearing races on worm and in parts 21 and 25. Check balls and cages for cracks and other defects. Look for flats and pitting of the worm faces and the tapered peg, and test the roller bearing 9 for wear. Renew both bearings if the worm is renewed.
Servicing the steering peg:
Just above the taper is a parallel shoulder. Nip this in a vice between soft jaws. Unlock and unscrew the nut on the other end. Release the vice and use a soft-faced hammer to drive the threaded end of the peg through the arm of the rocker shaft until the peg and rollers fall out. Remove the adjusting cone. Keep the rollers and cone together in their original positions.
When reassembling, put a thick layer of ballbearing grease or vaseline on the tapered races of the peg and cone. Fit the rollers with large ends on largest diameter of cone. Place adjusting cone and rollers into recess in arm of rocker shaft, then carefully push the peg into place, squeezing it in with a pair of pliers if necessary. Fit a new locking plate end nut, but do not tighten.
Grip peg in vice as in dismantling. Slightly bend up lugs of locking plate. Tighten nut gently until a slight resistance is felt when the peg is turned. This resistance must be slightly greater when a new bearing has been fitted. Lock the nut with two opposite tags of the locking plate. If it is necessary to use the old locking plate, always break off the lugs which were originally turned up.
FIG 9:5 Alignment marks on rocker shaft and drop arm (black arrow). White arrow points to dowel which locates steering gear on axle tube
The rocker shaft:
Normal play between the shaft and bushes should be .017 to .05 mm (.0008 to .002 inch). The wear limit is .06 mm (.0024 inch). Old bushes may be pressed out and new ones fitted and a new seal pressed in.
Reassembling steering gear:
Do this in the reverse sequence to dismantling. The worm is inserted from below, together with the upper bearing, which must be packed with grease. Do the same with the lower bearing and its outer race. Refit spacer 26.
The worm must turn freely, but without play. Adjustment is made by altering the number of shims 27, as shown in FIG 9:4. Tighten the end plate bolts moderately at first to check whether the worm is immovable. If it is, do not continue to tighten, but fit more shims.
Do not use paper gaskets when making this adjustment.
Fit the drop arm with marks coincident as shown in FIG 9:5. Tighten nut to a torque of 112 lb ft and fit a new splitpin. Put .25 litres (.44 pint) of Hypoid SAE.90 oil in the gearbox.
Adjustment:
This must be made with great care. The pressure point in the straight-ahead position must be, if anything, a little too loose rather than too tight. In the central position, free play at the rim of the steering wheel should be 10 mm (.40 inch). The explanation of the pressure point is that the worm is so shaped that if the tapered peg is engaged without play in the centre of the steering range, a deflection of the wheels of 3 deg. or more in either direction will increase the clearance so that there is actual play. Thus, the gear may be adjusted accurately at the pressure point with no danger of the peg binding at some other point in its travel.
To carry out the adjustment with the gear out of the car, set the marks on the worm shaft and the box in line. This will be the central steering position. To ensure that the position is correct, turn the shaft fully in one direction and then turn it back one turn and line up the marks. Slacken the locknut and turn the adjusting screw until a slight resistance to turning can be felt (see FIG 9:6).
If a torque measuring device is available set it to 4.34 to 6.08 lb inch. In effect, this is equivalent to mounting a lever at rightangles to the worm shaft and putting a weight of one lb at a distance of 4.34 to 6.08 inch from the centre of the shaft. The pressure point must not be noticeable when the car is under way, and any attempt to eliminate steering shocks by increasing the pressure is not permitted.
If the adjustment is made with the steering gear assembled in the car, disconnect the steering damper and the tie-rods from the drop arm. Turn the adjusting screw until a slight resistance is felt when turning the steering wheel through the central position.
It is essential when carrying out adjustments to the steering gear to ensure that the toe-in is correct (see Section 9:8).
When the steering gear is ready for refitting, refer to Section 9:4 for details of the procedure.
Removing:
1 Jack up car and remove front wheels. Remove split-pins and nuts on tie-rod joint pins.
2 Press out pins with special tool VW.266F or any similar commercial device. Do not attempt to drive the tapered pins out of the steering arms by hammering on the threads. FIG 9:7 shows the tool in operation.
3 When the tie rod joints are parted from the steering gear drop arm and steering arms, the rods may be taken away for examination.
Check the rods for damage or deformation. Renew bent rods. Do not try to straighten. Check the joints for wear. This is always greatest where the ballpin and the joint have been in the straight-ahead position, and any flats which form will make for erratic steering. Renew faulty joints or else renew complete tie-rods. Joints with ballpins which have damaged threads must not be reused.
Check grease nipples and renew those which are damaged or clogged. Fit angled nipples to the inner tie-rod joints.
Installing:
Fit in the reverse order to dismantling. The bend in the short tie-rod must be adjacent to the drop arm. Fit new splitpins to the ballpin castle nuts. Apply the grease gun to the nipples and check the toe-in according to the instructions in Section 9:8.
Removing:
Jack up car, remove front wheels. Remove splitpins from castle nuts at each end of damper. Location of damper is shown in FIG 8:1 in the preceding chapter. Remove castle nuts and lift damper away.
Check damper for steady resistance to opening and closing. Erratic performance calls for renewal. Check rubber bushes and renew if worn or deteriorated. Check condition of retaining clip on axle tube.
Installing:
Refer to FIG 9:8 and make sure that the retaining clip is correctly positioned with respect to the central bracket between the axle tubes. Fit the damper and tighten the castle nuts until they contact the rubber bushes. This will ensure freedom from wear and rattles. Fit new splitpins to nuts.
Accurate measurement of steering angles is the province of a service station equipped with an optical device. It is possible for an owner to carry out adjustment for correcting toe-in.
Steering angles:
These are shown as three diagrams in FIG 9:9.
Camber:
This is angle A in the lefthand view. It is determined by the angle which the stub axle makes to the horizontal. Inclination of the kingpin (angle B) is the angle which the kingpin makes to the vertical. Incorrect camber may be due to wrong radius arm adjustment or broken torsion bars giving rise to body tilt.
Castor:
This is shown in the central diagram as angle B. Castor action is determined by the rearward displacement of the stub axle relative to the kingpin (distance A) and the castor angle of the kingpin. The angle is affected by body tilt and may also be affected if measurements are taken with the front of the car heavily loaded. If the castor angle is not within the prescribed limits, check the inclination of the front axle tubes (angle C). If there is no error at this point, remove and check the suspension arms and stub axles separately.
FIG 9:6 Turning adjusting screw to set engagement of peg in worm. Alignment marks are adjacent to hand
Toe-in:
This is shown in the top righthand diagram. It is the amount by which the front wheels are nearer together at the front than the rear, taking measurements at wheel centre height. This compensates for the amount the front of the wheels will draw apart when the car is moving. This is due to rolling resistance of the tyres and to the taking-up of slack in the steering and suspension linkage. The difference between dimension A and dimension B is the amount of toe-in. Note that although there may be toe-in when the wheels are stationary and straight-ahead, this becomes toe-out on righthand or lefthand turns (see lower righthand diagram). The amount of toe-out is called the difference angle C, and if steering and tyre wear are not to be affected, the angles on equal steering locks must be the same. Effective checking is best entrusted to a service station with suitable equipment. If it is suspected that toe-in variations during springing movements is giving rise to oversteer, it is possible that the front axle tubes or steering arms are bent.
FIG 9:8 Steering damper clip must be 140 mm (5½ inch) from the central bracket between the axle tubes
Alignment tests:
During all wheel alignment tests, it is essential that the following points are observed:
1 All moving parts of the steering and suspension assembly must have the correct amount of play and no more.
2 The suspension system must be in good condition and the radius arms must be correctly adjusted.
3 The wheels must turn freely and brakes must not bind.
4 Wheels must run true and be effectively balanced.
5 Tyres must be correctly inflated and treads must not show uneven wear.
6 Dampers must be in good working order.
FIG 9:9 Front wheel camber angle A on left. Angle B is kingpin inclination. Central view shows castor angle B, trail of stub axle A and inclination of axle tubes C.
Front wheels toe-in (top right) so that A is less than B. On bends, wheels toe-out (bottom left). A and A1 are parallel, difference between A1 and B is angle C
Although some of these will have no effect on toe-in it is recommended that all the points should be checked if perfect steering and roadholding is desired.
Adjusting toe-in:
Although it is best to give this job to experts with the necessary equipment, a reasonably accurate setting may be obtained as follows:
Let the car come to rest with the wheels in a straight-ahead position. The ground must be smooth, level and horizontal, the car must be unladen and the test conditions previously mentioned must be met.
Refer to the top righthand view in FIG 9:9 and measure distances A and B between the rims at wheel centre height from the ground. Roll the car forward for half a wheel and repeat the measurements to compensate for uneven rims. The difference between measurements A and B is the amount of toe-out or toe-in.
Dimension A must be 2 mm (.08 inch) less than dimension B. The tolerance on this is ± 1 mm (± .04 inch). To adjust, slacken the clips securing the ball joints to the tie-rods (see 2 and 17 in FIG 8:1) and turn the rods in the same direction by equal amounts until the desired result is obtained. Tighten the clips so that the ball joints are in the same plane on each rod.
Setting steering wheel spokes:
It may happen that adjustment or overhauling results in the steering wheel being out of position when the front wheels are straight-ahead. The toe-in must be correct and the steering gear and steering wheel correctly assembled as explained in Section 9:3. The steering gear must be set at the ’Pressure point’ or central position as described under ’Adjustment’ in Section 9:5. If the steering wheel is now slightly out of position, correct this by slackening the ball joint clips on the tie- rods and turning each of them the same amount in opposite directions. This will make the necessary change without affecting the toe-in. Check that the toe-in is correct after making the adjustment in case an error has crept in somewhere.
(a) Wheel wobble
1 Unbalanced wheels and tyres
2 Worn or loose steering connections
3 Incorrect wheel alignment angles
4 Excessive play in steering gear
5 Worn or slack hub bearings
6 Faulty dampers
(b) Steering wander
1 Check 2,3 and 5 in (a)
2 Smooth front tyres, pressure too high or too low
(c) Heavy steering
1 Check 3 in (a)
2 Low or uneven tyre pressures
3 Faulty steering gear adjustment
4 Lubrication neglected
5 Front suspension worn or out of alignment
6 Steering gearbox wrongly mounted
7 Faulty steering damper
8 Weak or broken torsion bars
9 Steering column bent, bearing faulty
(d) Lost motion
1 Loose steering wheel, worn splines
2 Worn ball joints and suspension system
3 Drop arm loose on shaft
4 Steering gearbox loose at mounting
5 General wear and faulty adjustment of steering gearbox
(e) Steering pulls to one side
1 Check 3 in (a) and 2 in (c)
2 One front brake binding
3 Broken or sagging rear suspension
4 Bent front axle tubes
