57STEERING
2
REPAIR
13.Disconnect 3 switch multi-plugs.
14.Slacken clamp screw on top of switch cluster
and withdraw switch assembly.
15.Note position of harness leads on back of starter
switch and disconnect lucars. If fitted, remove
alarm system passive coil from switch
See
ELECTRICAL, Repair, Vehicle immobilisation
and alarm system
.
16.Using a punch or stud extractor remove 2 shear
bolts securing switch to column.
17.Remove switch and collect 2 plain washers
between switch and clamp.
18.Remove brake pedal box
See BRAKES,
Repair, Brake pedal
.
19.Remove bolt securing tie-bar to steering column,
behind instrument panel.
20.Remove 2 bolts securing column lower support
to mounting bracket.
21.Remove bolts securing two halves of top clamp
and bolts that secure top half of clamp to
bulkhead.
22.Remove clamp and rubber packing.
23.Remove 2 bolts securing column main support
bracket to bulkhead.
24.Remove steering column and main support
bracket from vehicle.
STEERING
3
REPAIR REV: 05/99
NOTE: The steering column is a non
serviceable component and can only be
serviced as a complete assembly.
25.Fit main support bracket and padding to steering
column and manoeuvre column into position in
vehicle.
26.Loosely secure main support bracket and
harness bracket to bulkhead.
27.Loosely fit clamp and rubber packing strip to
column.
28.Loosely secure lower end of column to lower
support bracket.
29.Loosely secure clamp bracket to main support
bracket.
30.Working inside vehicle cab, fit tie-bar to column
bracket and secure with single bolt to
22 Nm (16
lbf/ft).
31.Finally, tighten main support bracket, clamp
bracket, upper clamp, and lower support bracket
nuts and bolts. (M6 bolts
9 Nm (6 lbf/ft),M8
bolts
22 Nm (16 lbf/ft).
32.Fit brake pedal boxSee BRAKES, Repair,
Brake pedal
.
33.Fit steering lock/switch in position and rotate
steering column inner shaft to line up slot with
switch plunger.
34.Secure lock to column with clamp and shear
bolts. Evenly tighten bolts but do not shear them.
35.Temporarily fit steering wheel and operate
switch and lock mechanism several times to
ensure it functions correctly.
36.Fully tighten switch retaining bolts until heads
shear.
37.Connect electrical leads to rear of switch. Fit
alarm system passive coil, if applicable.
See
ELECTRICAL, Repair, Vehicle immobilisation
and alarm system
.
38.Fit switch assembly on steering column and
tighten clamping screw.
39.Connect switch assembly multi-plugs and
electrical leads to main harness.
40.Offer up instrument panel, connect speedometer
cable, multi-plugs and electrical leads to main
harness. If applicable, fit vehicle alarm system
connections.
See ELECTRICAL, Repair,
Vehicle immobilisation and alarm system
.
41.Secure panel with 4 screws.
42.Locate top half of nacelle in position and fit to
switch gaiters/grommets.43.Fit lower half of nacelle and loosely tighten fixing
screws.
44.Ensure switch gaiters/grommets are correctly
located and fully tighten fixings.
45.Turn indicator cancelling ring so that slots are
vertical and lug with arrow points to the left, in
direction of indicator switch.
46.Fit steering wheel with finisher attachment lug at
bottom, ensuring that indicator cancelling forks
locate in cancelling ring slots.
47.Secure wheel with nut and new shake-proof
washer. Tighten to
43 Nm (32 lbf/ft).
48.Fit steering wheel decal.
49.If necessary, fit new universal joints to support.
Note that long joint is fitted to short length of
shaft and short joint to long end. Joints can only
be fitted one way to shaft.
50.With steering lock engaged and road wheels in
straight ahead position, align reassembly marks,
and fit collapsible shaft assembly with long leg of
shaft to steering box. Fit pinch bolts and tighten
to
25 Nm (18 lbf/ft).
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.
FRONT SUSPENSION
3
REPAIR REV: 05/99 Refit
11.Assemble shock absorber components.
12.Position shock absorber, complete with bracket
and secure with 4 fixings.
13.Secure shock absorber lower fixing.
14.Fit road wheel, remove chassis stands and jack.
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)
FRONT ROAD SPRING
Service repair no - 60.20.11.
Remove
1.Remove front shock absorber
See Front
shock absorber
.
CAUTION: Avoid over stretching brake
hoses. If necessary, loosen hose
connector locknuts to allow hoses to
follow axle.
2.Lower axle sufficient to free road spring.
3.Withdraw road spring.
4.Withdraw shock absorber bracket securing ring.
Refit
5.Fit shock absorber bracket retaining ring. Retain
in position with a nut.
6.Position road spring and raise axle.
7.Remove nut retaining securing ring.
8.Fit front shock absorber
See Front shock
absorber
.
REAR SUSPENSION
1
REPAIR REV: 05/99 REAR ROAD SPRING
Service repair no - 64.20.01.
Remove
1.Loosen rear road wheel retaining nuts.
2.Support chassis on stands and remove wheels.
3.Support rear axle weight with jack.
4.Disconnect shock absorbers at one end.
5.Position coil spring compressor correctly on road
spring.
6.Compress spring evenly to facilitate removal.
7.Lower axle to free road spring from upper seat.
CAUTION: Avoid lowering axle further than
rear brake flexible hose will allow.
8.Remove spring retainer plate.
9.Withdraw road spring.
10.Collect spring seat.
Refit
11.Position spring seat on axle location.
12.Fit road spring into chassis location and, using a
turning motion, fit to spring seat.
13.Fit spring retainer plate. Tighten bolts to
14 Nm
(10 lbf/ft).
14.Secure shock absorber. Tighten fixing to37 Nm
(27 lbf/ft).
15.Fit road wheels, remove chassis stands and
jack. 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)
REAR SHOCK ABSORBER
Service repair no - 64.30.02.
Remove
1.Loosen road wheel retaining nuts.
2.Support chassis on stands. Remove road wheel
and support rear axle weight with jack.
3.Remove fixings and withdraw shock absorber
from axle bracket.
4.Remove upper fixings.
5.Withdraw shock absorber.
6.If required, remove mounting bracket
7.If required, remove mounting rubbers.
Refit
8.Position shock absorber and fit upper fixings.
9.Secure shock absorber with lower fixings to axle
bracket. Tighten upper and lower fixings to
37
Nm (27 lbf/ft).
10.Fit road wheels, remove chassis stands and
jack. 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)
BRAKES
1
DESCRIPTION AND OPERATION DESCRIPTION
The mechanical components of the hydraulic braking
system consists of four piston caliper disc brakes at
the front and two piston caliper disc brakes at the rear.
Vented front brake discs are fitted as standard on
110/130 models, while 90 models have solid discs.
However, on 90 models with a heavy duty chassis,
vented front discs may also be fitted.A cable controlled parking brake operates a single
drum brake mounted on the output shaft of the
transfer gearbox and is completely independent of the
main braking system.
The basic hydraulic system involves 2 separate and
independent primary and secondary circuits which
permits a degree of braking should a fault occur in
one of the circuits. The primary circuit operates the
rear brake calipers and the secondary circuit the front
brake calipers.
Master cylinder components
1.Secondary plunger
2.Secondary spring
3.Recuperation seal4.Primary spring
5.Recuperation seal
6.Primary plunger
70BRAKES
2
DESCRIPTION AND OPERATION REV: 05/99 OPERATION
Master cylinder
A tandem master cylinder, which is assisted by a light
weight, short, compact servo, is fed by a divided fluid
reservoir. The rear section supplies fluid for the
primary circuit and the front section the secondary
circuit.
When the brakes are off, the fluid can move
unrestricted between the dual line system and the
separate reservoirs in the fluid supply tank.
When the footbrake is applied, the primary plunger
assembly moves up the cylinder bore and the
pressure created acts in conjunction with the primary
spring to overcome the secondary springs, thus
moving the secondary plunger assembly up the bore.
At the same time initial movement of both plungers
takes the recuperating seals past the cut-off holes in
the cylinder chambers 'A' and 'C',see J6321, and
applies pressure to the fliud in those chambers, which
is directed to the respective circuits.
The fluid in chambers 'B' and 'D'is unaffected by
movement of the plungers and can move unrestricted
between the separate chambers and respective
reservoirs in the fluid supply tank, both before and
during brake application. When the brakes are
released, the plunger assemblies, aided by the return
springs are retracted faster than the fluid; this creates
a depression between the fluid in chambers 'A' and
'C'and the recuperation seals.
The recuperation seals momentarily collapse allowing
fluid in chambers 'B' and 'D'to flow through the holes
in the plungers, over the collapsed seals and into
chambers 'A' and 'C'respectively. The movement of
fluid from one set of chambers to the other, is
compensated for by fluid from the separate reservoirs
in the supply tank moving through the feed holes in
the cylinder. Conversely, the final return movement of
the plunger assemblies causes the extra fluid in
chambers 'A' and 'C'to move through the cut off holes
into the fluid reservoir.The servo unit provides controlled power assistance
to to the brake pedal when pressure is applied. Power
is obtained from a vacuum pump located on the RH
side of the engine cylinder block. The vacuum is
applied to both sides of a flexing diaphragm, and by
admitting atmosheric pressure to the rear diaphragm,
assistance is obtained. The servo unit is mounted
between the brake pedal and master cylinder and is
linked to these by push rods. Should a vacuum failure
occur, the two push rods will act as a single rod
allowing the brakes to function in the normal way,
although more effort will be required to operate the
brake pedal.
Hydraulic system
A brake fluid loss switch is fitted to the master cylinder
reservoir filler cap. The switch is wired to a warning
light on the vehicle fascia and will illuminate as a bulb
check when the ignition is switched on and
extinguishes when the engine is running and the
handbrake is released. A hydraulic failure in the
system will result in fluid loss, causing the warning
light to illuminate.
On 90 models a pressure reducing valve (PRV), fitted
to the RH bulkhead in the engine compartment,
maintains the braking balance, see J6322. Pressure
to the rear calipers is regulated by the PRV, this valve
is of the failure by-pass type, allowing full system
pressure to the rear brake calipers in the event of a
front (secondary) circuit failure.
NOTE: In some countries, a pressure
reducing valve may be fitted to 110 models
to conform to legal requirements.
BRAKES
3
DESCRIPTION AND OPERATION
90 Models
110/130 Models
Hydraulic system
A- Primary circuit
B- Secondary circuit
C- Pressure reducing valve (PRV)1.LH rear brake caliper
2.T connector
3.RH rear brake caliper
4.Brake servo
5.Master cylinder and reservoir
6.LH front brake caliper
7.RH front brake caliper