power steering LAND ROVER DEFENDER 1996 Owner's Manual

57STEERING
4
FAULT DIAGNOSIS Symptom:-
Fluid leaks from steering box seals.
CAUTION: The steering wheel must not be
held on full lock for more than 30 seconds
in one minute, as this may overheat the
fluid and cause damage to the oil seals.
1.Check fluid level
See Repair, Power Steering
Fluid Reservoir
.
Check fluid pressure
See Power Steering
System - Test
.
2.Is pressure high?
YES - Renew pump
See Repair, Power
steering Pump
.
If oil seal leaks persist after renewing the pump
See Overhaul, Power Steering Box.
NO -
See Overhaul, Power Steering Box.
Symptom:-
Insufficient power assistance - castor return
action normal.
1.Are tyres correct type and pressure?
NO -
See GENERAL SPECIFICATION DATA,
Information, Wheels and Tyres
.
YES - Continue.
2.Is fluid level correct?
NO - Check fluid level
See Repair, Power
Steering Fluid Reservoir
.
YES - Check system for air locks
See Repair,
Power Steering System - Bleed
.
3.Is pressure correct?
NO - Check fluid pressure
See Power Steering
System - Test
.
If pressure is not correct after bleeding the
system, renew pump
See Repair, Power
Steering Pump
.
YES -
See Overhaul, Power Steering Box.Symptom:-
Steering heavy - stiff, poor castor return action.
1.Are tyres correct type and pressure?
NO -
See INTRODUCTION, Information,
Wheels and Tyres
.
YES - Check universal joints for seizure and
correct alignment
See Repair, Lower Steering
Shaft and Universal Joints
.
Check power steering box adjustments
See
Overhaul, Power Steering Box
.
2.Is the power assistance satisfactory?
NO - See fault symptomInsufficient
assistance, (castor return action normal).
YES - Disconnect drag link from drop arm and
check steering column and box for stiffness
See
Repair, Drag Link and Drag Link Ends
.
3.Is the steering stiff with the drag link
disconnected?
NO - Check steering ball joints for seizure and
axle swivels lubrication and resistance
See
Repair, Drag Link and Drag Link Ends
,See
FRONT AXLE AND FINAL DRIVE, Overhaul,
Front Stub Axle, Constant Velocity Joint and
Swivel Pin Housing
.
YES - Disconnect the lower steering shaft and
check the column and box for stiffness
See
Repair, Lower Steering Shaft and Universal
Joints
.
4.Is the steering column stiff to turn when
disconnected from the box?
NO - Remove and overhaul box
See Overhaul,
Power Steering Box
.
YES - Adjust steering column
See Stiff
Steering Checklist
.

STEERING
5
FAULT DIAGNOSIS REV: 05/99 Symptom :-
Steering excessively light/sensitive. Excessive
freeplay at steering wheel.
1.Are steering box adjustments correct?
NO -
See Adjustment, Power Steering Box.
WARNING: Adjustments of steering box
should not be required while in warranty
period. If box is within warranty, it must be
returned to manufacturer. No attempt must be
made to introduce backlash.
YES - Suspect worn panhard rod or radius arm
bushes. Check condition of ball joints and the
lower steering column shaft universal joints for
wear
See Repair, Lower Steering Shaft and
Universal Joints
.
Symptom :-
Steering vibration, road wheel shimmy - wobble.
Vibration through the steering linkage powerful
enough to induce high frequency oscillation of the
steering wheel, is generally caused by out of balance
road wheels. However there are a number of other
possible causes of this symptom which if severe, may
be described as shimmy or wobble. Regardless of the
terminology used by the owner/driver to describe the
symptoms, the following diagnostic checks should be
carried out in the order presented.
1.Check the tyres and balance of the road wheels
See GENERAL SPECIFICATION DATA,
Information, Wheels and Tyres
,See
WHEELS AND TYRES, Fault diagnosis, Fault
- Symptoms See WHEELS AND TYRES,
Repair, Wheel Balancing .
2.Check the steering hydraulic damper function
See Steering Damper.
3.Check steering column universal joints for wear
and correct alignment
See Repair, Lower
Steering Shaft and Universal Joints
.4.Check steering linkage ball joints for wear,
correct alignment and security, including steering
box and tie rod
See Steering Linkage Inspect
.
5.Check all front suspension rubbers for wear.
Check all fixing torques, including radius arm
bushes, panhard rod and anti-roll bar
See
FRONT SUSPENSION, Repair, Panhard Rod
,
See FRONT SUSPENSION, Repair, Radius
Arm
,See FRONT SUSPENSION, Repair,
Anti-Roll Bar
,See FRONT SUSPENSION,
Repair, Front Shock Absorber
.
6.Fit new radius arm bushes using NTC 6781. Fit
new nuts, bolts and washers.
7.If problem persists fit damper kit STC 288 - 90,
STC 290 - 110/130 (2 off front) and STC 289 -
90, STC 291 - 110 levelled, STC 292 - 110
unlevelled, STC 293 - 130 (2 off rear). Road test
vehicle.
8.Check the power steering box adjustments and
operation
See Overhaul, Power Steering Box.
9.Check the hub bearing end floats and determine
the condition of the hub bearings as applicable
See FRONT AXLE AND FINAL DRIVE, Repair,
Front Hub Assembly
.
10.Check the resistance and condition of the
swivels
See FRONT AXLE AND FINAL DRIVE,
Description and operation, Description
.
If problem is not diagnosed: Repeat checks
starting at 1.
11.Carry out a full steering geometry check
See
GENERAL SPECIFICATION DATA,
Information, Steering
.

57STEERING
8
FAULT DIAGNOSIS 4. DIRECTIONAL STABILITY
From 1. GENERAL STEERING:
1.Is directional stability concern when vehicle is
towing?
YES - Check towing/vehicle loading parameters
in Owner's Handbook.
NO - go to 3.
2.Is problem resolved?
YES - end
NO - continue.
3.Check condition of rear trailing link/chassis
bushes.
4.Is problem resolved?
YES - end
NO - continue.
5.Check condition of front and rear shock
absorbers. If necessary, change units in pairs,
side to side.
6.Is problem resolved?
YES - end
NO - continue.
7.Check steering damper
See Steering Damper
.
8.Is problem resolved?
YES - end
NO - continue.
9.Check wheel balance
10.Is problem resolved?
YES - end
NO - contact local technical office.POWER STEERING FLUID LEAKS
1.Is fluid level correct?
YES - go to 3.
NO - Refill or drain to correct level. Bleed
system, check for leaks
See Repair, Power
Steering System - Bleed.
2.Is problem resolved?
YES - end
NO - continue.
3.Are hoses or joints leaking? Check on full lock
with engine at 2000 rev/min.
YES - loosen and retorque joints.
NO - go to 6.
4.Does leak remain?
YES - change PAS pipe.
NO - end.
5.Does leak remain?
YES - suspect seal in component. Check and
replace as necessary.
NO - end.
6.Is oil escaping from filler cap?
YES - bleed system
See Repair, Power
Steering System - Bleed.
NO - go to 8.
7.Is oil still escaping from filler cap?
YES - go back to 1.
NO - end.
8.Is oil leaking from PAS pump?
YES - go to 10.
NO - continue.
9.Is oil leaking from PAS box?
YES - go to 10.
NO - end.
10.Clean unit, add tracer dye to system. Retest
11.Is oil still leaking?
YES - establish leak point. Repair or replace unit
as necessary.
NO - end.

STEERING
9
FAULT DIAGNOSIS POWER STEERING SYSTEM - EXCESSIVE NOISE
1.Is fluid level correct?
YES - go to 3.
NO - Refill or drain to correct level. Bleed
system, check for leaks
See Repair, Power
Steering System - Bleed
.
2.Is problem resolved?
YES - end
NO - continue.
3.Is pressure hose from pump to box touching
body in a hard foul condition?
YES - route hose away from body.
NO - go to 5.
4.Does noise remain?
YES - continue.
NO - end.
5.Is noise a whistle or hiss on full lock?
YES - noise is not a fault unless excessive.
Compare with other vehicles
NO - go to 8.
6.Is noise excessive?
YES - continue.
NO - end.
7.Change steering box and/or pump.
8.Is noise a squeal on full lock?
YES - check drive belt tension and remove belt if
necessary
See ELECTRICAL, Repair,
Auxiliary drive Belt
.
NO - go to 10.
9.Does squeal remain?
YES - drive belt contaminated, change belt.
NO - end.
10.Is noise a continuous moan?
YES - bleed PAS system
See Repair, Power
Steering System - Bleed
.
NO - go to 13.
11.Does moan remain?
YES - do figure 8 manoeuvres.
NO - end.
12.Does moan remain?
YES - continue
NO - end.13.Is noise an intermittent "grunt"?
YES -
See Power Steering System - Grunt.
NO - continue.
14.Is it a clunking noise?
YES - check drive belt tension and renew belt if
necessary
See ELECTRICAL, Repair,
Auxiliary drive Belt
.
NO - contact local technical office.
15.Does noise remain?
YES - Suspect suspension or drive train.
NO - end.
POWER STEERING SYSTEM - GRUNT
Steering box grunts intermittently when turning
from lock to lock:
1.Is fluid level correct?
YES - go to 3.
NO - refill or drain to correct level. Bleed system,
check for leaks
See Repair, Power Steering
System - Bleed
.
2.Does grunt remain?
YES - continue
NO - end.
3.Is correct low pressure hose, steering box to
reservoir, fitted?
YES - go to 5.
NO - Fit correct hose.
4.Does grunt remain?
YES - continue
NO - end.
5.Purge box by doing figure 8 manoeuvres e.g. on
car park, followed by 10 minutes normal road
use.
6.Does grunt remain?
YES - Contact local technical office
NO - end.

STEERING
11
FAULT DIAGNOSIS STIFF STEERING CHECKLIST
NOTE: Having completed visual checks
and steering assessment and confirmed
that vehicle steering load is incorrect carry
out the following procedure in order shown.
Steering wheel 'torque to turn' loads
1.Raise vehicle so both front wheels free.
2.With engine off, centralise steering wheel, and
remove steering wheel decal. Using torque
wrench on column nut, check torque required to
turn the steering wheel one turn in each
direction.
3.Record readings obtained in each direction.
Reading should be
4.40 Nm (3.5 lbf/ft).
NOTE: If figures are in excess of that
specified carry out steering box tie bar
reset below. If figures are as specified
See
Visual Check and Basic Adjustments
.
Steering box tie bar reset
1.Loosen the tie bar fixings one complete turn.
2.Drive vehicle carefully a short distance (within
the dealership) applying full lock in both
directions in order to settle steering components.
Drive vehicle over speed bumps and include
harsh braking if possible.
WARNING: Do not drive on public
highway.
3.Near end of operation 2. ensure vehicle is driven
in a straight line on level ground and halted.
4.Tighten panhard rod mounting arm nut to
110
Nm (81 lbf/ft).
5.Tighten the 2 fixings, tie bar to steering box, to
81 Nm (60 lbf/ft).
6.Recheck steering wheel torque to turn. If torque
reading is still greater than specified, carry out
steering shaft universal joint lubrication.Lower steering shaft universal joint lubrication
1.Check lower steering shaft is correctly phased
See Repair, Lower Steering Shaft and
Universal Joints
.
2.Lubricate universal joints with an anti-seizure
type penetrating spray. Work the joints to ensure
full penetration of the spray by driving vehicle
and steering from lock to lock.
3.If steering stiffness still persists carry out swivel
pin preload setting.
Swivel pin preload setting
1.The swivel pin preload setting must be checked
and set
See FRONT AXLE AND FINAL DRIVE,
Overhaul, Front Stub Axle, Constant Velocity
Joint and Swivel Pin Housing
.
Note that a pull load of 1.16 - 1.46 kg is required
after the axle shaft and swivel housing seal have
been removed.
Steering box adjustment
1.Check steering box adjustment
See
Adjustment, Power Steering Box
.
Steering damper check
1.Check condition of steering damper
See
Steering Damper
.

57STEERING
12
FAULT DIAGNOSISREV: 05/99 VISUAL CHECK AND BASIC ADJUSTMENTS
NOTE: It is important that the following
instructions are carried out in the
sequence shown and the results recorded.
1.Road springs - check that road springs are
correctly seated and are to correct specification
for vehicle. For spring specification
See
GENERAL SPECIFICATION DATA,
Information, Road Spring Data
.
2.Ride height - measure trim height from wheel
centre to wheelarch eyebrow. Record results on
data sheet.
3.Check/top up power steering fluid
See Repair,
Power Steering Fluid Reservoir
.
4.Check tension and condition of drive belt
See
ELECTRICAL, Repair, Auxiliary drive belt
.
5.Track rod/drag link - check condition of track rod,
drag link and ball joints
See Repair, Drag Link
and Drag Link Ends
.
If either component is damaged, check operation
of steering damper and steering box for
smoothness. Replace all damaged or worn
components that impair the operation of the
steering system.
6.Suspension bushes - examine all steering and
suspension bushes for signs of wear and
deterioration. Also check all fixings for torque
relaxation. Tighten to correct torque value
See
FRONT SUSPENSION, Specifications, torque,
Torque Values
.
7.Oil leaks - check front and rear axle hubs for
leak and repair as necessary.
8.Brake system - check brake system for leaks,
pipe condition, pad wear/contamination, disc
wear/condition.
9.Hub end float - check movement in the hubs by
rocking the wheels.
10.Check front wheel alignment. Vehicles displaying
a tendency to veer more than considered
allowable, it is permissible to set the front track
to parallel.11.Having completed all the above checks and
adjustments, road test vehicle
See Road Test
Procedure
.
Attempt to reproduce the symptoms established
earlier. If symptoms still exist refer to relevant
Diagnostic Chart.
STEERING LINKAGE INSPECT
NOTE: When inspecting steering linkages
and ball joints for wear the following items
must be checked.
Steering ball joints
1.Check ball joint rubber boots for security, signs
of cracking or deterioration.
2.Check ball joint assemblies for seizure i.e. no
movement on ball joint and associated
assemblies.
3.Check for excessive wear. This will be evident
as extreme movement on track rod and steering
linkages. Renew parts as necessary
See
Repair, Track Rod and Linkage
,See Repair,
Drag Link and Drag Link Ends
.
Steering linkages
1.Check all linkages for wear, deterioration and
damage. Renew parts as necessary
See
Repair, Track Rod and Linkage
,See Repair,
Drag Link and Drag Link Ends
.

STEERING
1
ADJUSTMENT POWER STEERING BOX - ADJUST
Service repair no - 57.35.01
WARNING: Adjustments of steering box
should not be required while in warranty
period. If box is stiff or tight and within
warranty, it must be returned to manufacturer. No
attempt must be made to introduce backlash.
1.Apply park brake brake, chock wheels and Jack
up front of vehicle until wheels are clear of
ground.
2.Support chassis front on axle stands.
3.Disconnect drag link from steering drop arm.
4.Check torque to turn
See Fault diagnosis,
Stiff Steering Checklist
.
5.Centralise steering box
See Centralise
Steering Box
.
NOTE: Only check for no backlash when
steering box is in central position.
NOTE: If steering wheel is not straight, it
should be repositioned
See Repair,
Steering Wheel
.
6.Adjustment is obtained by rocking the drop arm
about centre whilst an assistant slowly tightens
the steering box adjuster screw.
7.Tighten locknut when all backlash has been
removed.8.Repeat the check for backlash. If backlash exists
loosen locknut and repeat adjustment
procedure.
9.Turn steering wheel lock to lock and check no
tightness exists.
10.Ensure front wheels are aligned and in straight
ahead position.
11.Adjust drag link 924 mm between ball joint
centres.
12.Connect drag link and tighten to
40 Nm (30
lbf/ft).
13.Lower vehicle to ground level and remove
chocks.
14.Road test vehicle
See Fault diagnosis, Road
Test Procedure
.
Drag link adjust
1.RH drive vehicles - if steering wheel is to right,
drag link is too long. If steering wheel is to left
drag link is too short.
LH drive vehicles - if steering wheel is to right,
drag link is too short. If steering wheel is to left
drag link is too long.
2.Adjust drag link until steering wheel points
straight ahead when vehicle is travelling in a
straight line.
CENTRALISE STEERING BOX
Service repair no - 57.35.05
LH drive vehicle
1.Disconnect drag link from drop arm
See Repair,
Drag link and drag link ends
.
2.Turn steering wheel on full RH lock.
3.Turn steering wheel back exactly two turns.
4.Fit drag link
See Repair, Drag link and drag
link ends
.
RH drive vehicle
1.Repeat operation for LH drive vehicle but turn
steering wheel on full LH lock.

STEERING
3
ADJUSTMENT FRONT WHEEL ALIGNMENT
Service repair no - 57.65.01
Checking Toe-out dimensions
NOTE: Recognised front wheel alignment
and tracking equipment should be used
for this operation. Only the use of basic
equipment is described below. No Adjustment is
provided for castor, camber or swivel pin
inclinations.
1.Set vehicle on level ground with road wheels
positioned straight ahead.
2.Push vehicle back and forwards to settle linkage.
3.Set up the equipment to manufacturers
instructions and check alignment as advised by
equipment supplier.
4.Position trammel probes on inner face of wheel,
not the rims, if the latter are damaged.
5.Measure toe-out at horizontal centre-line of
wheels.
6.Check tightness of clamp bolt fixings. Tighten to
14 Nm (10lbf/ft).
Adjust
7.Slacken clamps at both ends of track rod.
8.Rotate track rod to increase or decrease its
effective length until correct toe-out is obtained
See GENERAL SPECIFICATION DATA,
Information, Steering
.
9.Push vehicle rearwards turning steering wheel
from side to side to settle ball joints. With road
wheels set in straight ahead position, push
vehicle forward a short distance.
10.Recheck track and adjust if necessary.
11.When alignment is correct, tap ball joints in
direction of arrows to maximum of travel, to
ensure full unrestricted movement of track rod.
12.Tighten clamp bolts to
14 Nm (10 lbf/ft).
POWER STEERING PUMP DRIVE BELT
Service repair no - 57.20.01
Adjust
NOTE: For details of drive belt adjust
procedure.
See ELECTRICAL, Repair,
Auxiliary Drive Belt

57STEERING
4
REPAIR POWER STEERING BOX
Service repair no - 57.10.01
NOTE: A chassis undertray may be fitted
on some vehicle derivatives to conform to
legal requirements. When under chassis
remove and refit procedures are required, it may
be necessary to remove the undertray
See
CHASSIS AND BODY, Repair, Front undertray
.
General precautions
·Whenever any part of system, is removed or
disconnected, utmost cleanliness must be
observed.
·Disconnected ports and hoses must be
plugged to prevent ingress of dirt. If metal
sediment is found in system, establish cause,
rectify and flush system.
·Do not start engine until reservoir is full as
pump will be damaged.
·Metric pipe fittings are used with 'O' ring pipe
ends on fittings to steering box.
·Follow normal 'O' ring replacement procedure
whenever pipes are disconnected.
·Ensure compatible metric components when
fitting replacement pipes.
CAUTION: After refitting steering linkage
parts follow correct procedure to ensure
that road wheels, steering box and
steering wheel are correctly positioned relative to
each other when in straight ahead condition.
NOTE: When drag link is disconnected
from steering box, travel available at
steering wheel to each full lock is not
equal.
Remove
1.Site vehicle on level surface.
2.Apply park brake, chock rear wheels, raise
vehicle and locate axle stands. Alternatively,
raise vehicle on a hoist.
3.Remove road wheel.
4.Remove panhard rod
See FRONT
SUSPENSION, Repair, Panhard rod
.
5.Disconnect steering damper from drag link.
6.Disconnect drag link from drop arm, see J6305
on opposite page, using a suitable extractor.
7.Slacken, but do not remove nut securing tie bar
to mounting arm.8.Remove 2 bolts securing tie bar to steering box
and move aside.
9.Remove filler cap from power steering fluid
reservoir.
10.Position suitable container under steering box.
11.Disconnect feed and return pipes from steering
box and drain fluid.
12.Plug open pipes and steering box ports to
prevent ingress of dirt. Refit fluid reservoir filler
cap.
13.Centralise steering
See Centralise steering
box
.
14.Remove pinch bolt securing lower shaft
universal joint to power steering box.
15.Remove 4 bolts and 2 tab washers securing
steering box to chassis side member.
16.Withdraw steering box.
17.Clean all mounting faces, unions etc. prior to
refitting.
Refit
18.Position steering box to chassis side member,
ensuring locating peg is engaged. Fit tab
washers and tighten bolts to
81 Nm (60 lbf/ft).
19.Fit pinch bolt and nut securing universal joint to
power steering box spline. Tighten to
25 Nm (18
lbf/ft).
20.Secure tie bar to mounting arm and steering box.
Tighten fixings to
81 Nm (60 lbf/ft),starting with
tie bar to mounting nut, then loosen fixings by
one complete turn.
21.Check steering box and adjust if necessary
See
Adjustment, Power steering box - adjust
.
22.Refit drag link to drop arm and tighten nut to
40
Nm (30 lbf/ft).
Fit new split pin to retaining nut.

STEERING
5
REPAIR REV: 05/99
23.Fit panhard rodSee FRONT SUSPENSION,
Repair, Panhard rod
.
24.Fit road wheels. Lower vehicle to ground and
tighten wheel nuts to correct torque:
Alloy wheels - 130 Nm (96 lbf/ft)
Steel wheels - 100 Nm (80 lbf/ft)
Heavy duty wheels - 170 Nm (125 lbf/ft)
25.Remove plugs and refit feed and return pipes to
steering box. Tighten 16mm thread to
20 Nm (15
lbf/ft),
14mm thread to15 Nm (11 lbf/ft).
26.Remove filler cap. Fill reservoir to oil level mark
on dipstick, using recommended fluid
See
LUBRICANTS, FLUIDS AND CAPACITIES,
Information, Recommended lubricants and
fluids
.
27.Bleed power steering system
See Power
steering system - bleed
.
28.Recheck fluid level and replace cap.
29.With engine running, test steering system for
leaks by holding steering in both full lock
directions.
CAUTION: Do not maintain this pressure
for more than 30 seconds in any one
minute, to avoid oil overheating and
possible seal damage.
30.Test drive vehicle: using both full lock directions,
to settle steering components. If possible, drive
vehicle over uneven ground and include harsh
braking.
WARNING: Do not test drive vehicle on
public highway.
31.Drive vehicle in a straight line on level ground
and stop.
32.Tighten tie bar to mounting nut to
110 Nm (81
lbf/ft).
33.Tighten tie bar to steering box fixings to81 Nm
(60 lbf/ft).
34.Ensure steering wheel is correctly aligned when
wheels are positioned straight ahead.
35.If necessary, reposition steering wheel
See
Steering wheel
.
36.Road test vehicle.