1996 LAND ROVER DEFENDER engine

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.

57STEERING
6
REPAIR POWER STEERING SYSTEM - BLEED
Service repair no - 57.15.02
1.Check that fluid level is at maximum level
See
MAINTENANCE , Under bonnet maintenance.
2.Run engine to normal operating temperature.
3.Recheck reservoir fluid level, top up if necessary
NOTE: During operations 4 to 6, maintain
maximum fluid level in reservoir. Do not
increase engine speed or move steering
wheel.
4.With engine at idle speed, slacken bleed screw.
When fluid seeps past bleed screw retighten
screw.
5.Check fluid level.
6.Clean away fluid around bleed screw.
7.Check hose connections, pump and steering box
for fluid leaks by holding steering on full lock in
both directions.
CAUTION: Do not maintain this pressure
for more than 30 seconds in any one
minute to avoid overheating fluid and
possibly damaging seals.
8.Carry out road test.POWER STEERING FLUID RESERVOIR
Service repair no - 57.15.08
Remove
1.Position drain tin beneath reservoir.
2.Slacken mounting bracket clamp bolt and raise
reservoir to gain access to feed and return hose
retaining clips.
3.Slacken clips, disconnect hoses from reservoir,
allow fluid to drain.
4.Remove reservoir.
CAUTION: Plug connections to prevent
ingress of dirt.
CAUTION: Discard fluid drained from
system. Do not allow fluid to contact
paintwork, if spilled, remove fluid and
clean area with warm water.
Refit
5.Position reservoir, connect feed and return
hoses and tighten clips to
3 Nm (2 lbf/ft).
6.Fit reservoir in clamp, tighten clamp bolt.
7.Fill reservoir between upper mark and end of
dipstick with power steering fluid
See
MAINTENANCE , Under bonnet maintenance
.
8.Bleed power steering system
See Power
steering system - bleed
.

STEERING
7
REPAIR POWER STEERING PUMP
Service repair no - 57.20.14
Remove
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
.
1.Disconnect battery.
2.Remove viscous fan unit
See COOLING
SYSTEM, Repair, Viscous coupling and fan
.
3.Restrain steering pump pulley, slacken but do
not remove 3 bolts securing pulley.
4.Remove drive belt
See ELECTRICAL, Repair,
Auxiliary drive belt
.
5.Remove bolts and remove pulley.
6.Position suitable container beneath steering
pump.
7.Slacken retaining clip and disconnect return
hose from steering pump.
8.Disconnect high pressure pipe from steering
pump.
9.Allow steering fluid to drain into container.
CAUTION: Plug all connections to prevent
ingress of dirt.
10.Remove 4 bolts securing steering pump bracket
to engine auxiliary mounting bracket.
11.Remove pump and bracket assembly.
12.Remove 3 bolts and detach mounting bracket
from pump.
Refit
13.Fit mounting bracket to replacement steering
pump. Tighten bolts to
9 Nm (7 lbf/ft).
14.Fit pump and bracket to auxiliary mounting
bracket. Tighten bolts to
35 Nm (26 lbf/ft).
15.Connect high pressure feed pipe to steering
pump and tighten to
20 Nm (15 lbf/ft).
16.Connect return hose to steering pump. Tighten
retaining clip to
3 Nm (2 lbf/ft).
17.Position pulley to steering pump, coat threads of
bolts with Loctite 242; fit but do not fully tighten
bolts.
18.Fit drive belt
See ELECTRICAL, Repair,
Auxiliary drive belt
.
19.Restrain steering pump pulley, tighten bolts to
10
Nm (7lbf/ft).
20.Fit viscous fan unitSee COOLING SYSTEM,
Repair, Viscous coupling and fan
.
21.Bleed power steering system
See Power
steering system - bleed
.
POWER STEERING PUMP DRIVE BELT
Service repair no - 57.20.02
NOTE: For details of drive belt remove and
refit
See ELECTRICAL, Repair, Auxiliary
drive belt
.

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
1
REPAIR GENERAL BRAKE SERVICE PRACTICE
Brake fluid precautions
WARNING: Do not allow brake fluid to
come into contact with eyes or skin.
CAUTION: Brake fluid can damage
paintwork, if spilled wash off immediately
with plenty of clean water.
CAUTION: Use only correct grade of brake
fluid. If an assembly fluid is required use
ONLY brake fluid. Do NOT use mineral oil,
i.e. engine oil etc.
CAUTION: Thoroughly clean all brake
calipers, pipes and fittings before
commencing work on any part of the brake
system. Failure to do so could cause foreign
matter to enter the system and cause damage to
seals and pistons which will seriously impair the
efficiency of the brake system. To ensure the
brake system efficiency is not impaired the
following warnings must be adhered to :-
·DO NOT use any petroleum based cleaning
fluids or any proprietary fluids containing
petrol.
·DO NOT use brake fluid previously bled from
the system.
·DO NOT flush the brake system with any fluid
other than the recommended brake fluid.
The brake system should be drained and flushed
at the recommended service intervals.
Cover all electrical terminals carefully to make
absolutely certain that no fluid enters the
terminals and plugs.FLUID LEVEL CHECK/TOP UP
WARNING: Clean reservoir body and filler
cap before removing cap. Use only fluid
from a sealed container.
1.Park vehicle on level ground.
2.Check level is between 'MIN' and 'MAX' marks.
3.If level is below 'MIN' mark top up fluid level to
'MAX' mark on reservoir, using correct fluid.
See
LUBRICANTS, FLUIDS AND CAPACITIES,
Information, Recommended lubricants and
fluids
CAUTION: Do not fill reservoir above
maximum line.

70BRAKES
4
REPAIR PRESSURE REDUCING VALVE (PRV)
Service repair no - 70.25.21
Remove
1.Disconnect battery.
2.Clean area around reducing valve ports.
3.Place a container under valve to catch escaping
brake fluid.
4.Disconnect primary circuit pipe unions ñAñ
from valve.
5.Disconnect secondary circuit pipe unions ñBñ
from valve.
6.Cover pipes to prevent ingress of dirt.
7.Remove single retaining nut and bolt securing
valve to engine bulkhead.
8.Remove valve.
Refit
9.Fit valve to engine bulkhead. Tighten bolt to
15
Nm (11 lbf/ft).
10.Connect primary and secondary circuit pipes to
valve. Tighten to
16 Nm (12 lbf/ft).
11.Fill brake reservoir with recommended brake
fluid
See LUBRICANTS, FLUIDS AND
CAPACITIES, Information, Recommended
lubricants and fluids
.
12.Bleed the brake system
See Brake system
bleed
.
13.Reconnect battery and road test vehicle.SERVO NON RETURN VALVE
Service repair no - 70.50.15
Remove
1.Disconnect brake vacuum hose from servo non
return valve.
2.Carefully prise valve out with a screwdriver blade
between valve and grommet. Take care not to
exert too much pressure on the vacuum
chamber.
3.Remove rubber grommet but be careful not to
allow it to fall into the vacuum chamber.
4.Check the valve for correct operation; it should
not be possible to pass air through into the servo
in direction of arrow. Do not use compressed air.
Refit
5.Fit rubber grommet.
6.Smear ribs of the valve with Lucas Girling rubber
grease to assist assembly, and push valve fully
home.
7.Connect vacuum hose to the valve.
8.Road test vehicle.

BRAKES
5
REPAIR SERVO ASSEMBLY
Service repair no - 70.50.01
Remove
Before starting repair refer to general brake service
practice
See General Brake Service Practice.
NOTE: The non-return valve and grommet,
are the only serviceable components. In
event of failure or damage, fit a new unit.
1.Remove master cylinderSee Master cylinder.
2.Disconnect vacuum supply hose from servo unit.
3.At footwell, release 2 brake pedal return springs.
4.Disconnect leads from brake light switch at rear
of pedal box.
5.Remove blanking grommets from each side of
pedal box.
6.Remove split pin and clevis pin securing servo
push rod to brake pedal.
7.Remove 4 nuts and plain washers securing
servo to pedal box.
8.Remove servo assembly and rubber washer
from bulkhead.Refit
9.Locate servo assembly and rubber washer to
engine bulkhead and secure to pedal box.
Tighten fixings to
14 Nm (10 lbf/ft).
10.Fit brake pedal to servo push rod with clevis pin
and new split pin.
11.Fit blanking grommets to each side of pedal box.
12.At footwell, attach pedal return springs.
13.Connect vacuum hose to servo non-return valve.
14.Fit brake master cylinder to servo unit
See
Master cylinder
.