1996 LAND ROVER DEFENDER ventilation

REAR AXLE AND FINAL DRIVE
1
FAULT DIAGNOSIS FAULT DIAGNOSIS
Complaint - Oil leaks
An external leak of lubrication from the hub seals can
be caused by a faulty internal seal. For example, if the
seals which separate the differential from the hubs are
faulty and the vehicle is operating or parked on an
embankment, oil from the differential may flood one
hub resulting in a lack of lubrication in the differential.
When a seal is found to be leaking check the axle
ventilation system, as a blockage can cause internal
pressure to force oil past the seals.
See 'Description and Operation' for illustrations of oil
seal locations.
When investigating hub seal leaks check the grease
for dilution with oil. Also check the differential oil level,
for signs of metal particles in the oil and the condition
of internal seals.
If the vehicle is driven in deep water with defective oil
seals, water may contaminate the lubricants and raise
the differential oil level, giving a false impression that
the housing has been overfilled.
Do not assume that a high oil level in the
differential is due to over filling or, that a low level
is because of an external leak.

FRONT AXLE AND FINAL DRIVE
1
DESCRIPTION AND OPERATION DESCRIPTION
The welded steel front axle casing houses a separate
spiral bevel type differential unit, which is off-set to the
right of the vehicle centre line. The differential unit
drives the front wheels via the axle shafts and
constant velocity joints which are totally enclosed in
the spherical and swivel housings.The front wheels are pivoted on tape roller bearings at
the top and bottom of the swivel housing. The wheel
hubs on all axles are supported by two taper bearings
and driven by drive flanges which are splined to the
one piece, stub shaft/constant velocity joint.
Front axle hub and swivel housing
1.Axle casing
2.Ventilation pipe
3.Axle shaft
4.Wheel studs and hub
5.Stub axle
6.Wheel bearings
7.Inner and outer hub seals
8.Axle shaft seal
9.Hub lock plate, thrust washer and nuts
10.Brake disc
11.Drive flange
12.Shim washer and circlip13.Dust cap
14.Constant velocity joint/shaft
15.Thrust collar for CV joint
16.Roller bearing
17.Spacer
18.Circlip
19.Top and bottom swivel taper bearing
20.Top and bottom swivel pins
21.Spherical housing, seal and retainer
22.Swivel housing
23.Constant velocity shaft seal

54FRONT AXLE AND FINAL DRIVE
2
DESCRIPTION AND OPERATION Lubrication
The differential, swivel pin housing and wheel hubs
are indiviudally lubricated and separated by oil seals
(7) and (8), see J6267A, to prevent oil transfer across
the axle when the vehicle is traversing steep inclines.
The wheel bearings are lubricated with grease and the
swivel housing and differential with oil. On later
vehicles, identified by having only a filler plug in the
swivel housing, grease is used to lubricate the
housing assembly,
Ventilation
Ventilation of the differential is through a plastic pipe
(2) which terminates at a high level in the vehicle axle.
The swivel housings ventilate through axle shaft oil
seals (8) into the differential and the hub bearings
vent via the oil seals into the swivel housing.

FRONT AXLE AND FINAL DRIVE
1
FAULT DIAGNOSIS FAULT DIAGNOSIS
Complaint - Oil leaks
An external leak of lubrication can be caused by a
faulty internal seal. For example, if the seals which
separate the differential from the swivel housings are
faulty and the vehicle is operating or parked on an
embankment, oil may leak across the axle leaving one
swivel with a high level and the opposite swivel and
differential lacking lubrication.
See 'Description and Operation' for illustrations of oil
seal locations.
When investigating leaks or checking oil levels, it is
essential that all the lubrication is drained from any
housing with a high level and that the other levels are
checked.
Swivel oil should be checked for signs of grease
leaking from the hub bearings and oil contamination of
the hub grease.
Check that the axle ventilation system is clear, as a
blockage can cause internal pressure to force oil past
the seals.
If the vehicle is driven in deep water with defective oil
seals, water may contaminate the lubricants and when
checked, give a false impression that the housing has
been overfilled with oil.
Do not assume that a high oil level is due to over
filling or, that a low level is because of an external
leak.

FRONT AXLE AND FINAL DRIVE
1
REPAIR REV: 05/99 FRONT AXLE ASSEMBLY
Service repair no - 54.10.01
Remove
WARNING: Remove and refit of axle
requires a further two persons to steady
axle when lowering or repositioning axle.
1.Support chassis front.
2.Remove road wheels.
3.Support axle weight with hydraulic jack.
4.Remove radius arms to chassis frame nuts.
5.Disconnect steering damper from track rod.
Using a extractor remove track rod links from
swivel pin arms.
6.Remove four nuts and bolts securing radius
arms to axle bracket.
7.Remove radius arms.
8.Remove bolts securing brake hose brackets .
Refit bolts to prevent oil leakage.
9.Remove bolts from brake calipers and tie to one
side.
10.Remove nuts and washers securing shock
absorbers to axle.
11.Disconnect drag link from swivel pin housing
arm.
12.Remove two nuts and bolts securing panhard
rod to axle bracket. Lift rod clear of axle.
13.Mark for reassembly drive shaft flanges.
Remove four nuts and bolts, tie propeller shaft to
one side.
14.Release axle ventilation pipe banjo and lower
axle assembly. Remove road springs.
15.Disconnect anti-roll bar link
See FRONT
SUSPENSION, Repair, Anti-roll bar ball
.
16.Remove axle assembly.
Refit
17.Position axle under vehicle, supporting left side
of axle, and fit anti-roll bar links
See FRONT
SUSPENSION, Repair, Anti-roll bar links
.
18.Fit propeller shaft. Tighten bolts to
47 Nm (35
lbf/ft).
19.Fit panhard rod to axle bracket. Tighten bolts to
88 Nm (65 lbf/ft).
20.Fit drag link to swivel pin arm. Tighten fixings to
40 Nm (30 lbf/ft).
21.Fit shock absorbers to axle.
22.Fit brake calipers. Tighten bolts to
82 Nm (60
lbf/ft).
23.Tighten upper swivel pin bolts to78 Nm (58
lbf/ft).
24.Fit radius arms to axle brackets. Tighten bolts to
197 Nm (145 lbf/ft).
25.Fit steering damper to track rod.
26.Fit radius arms to chassis side member. Tighten
fixings to
197 Nm (145 lbf/ft).
27.Tighten track rod end to40 Nm (30 lbf/ft)and fit
new split pin.
28.Remove chassis supports, fit road wheels and
tighten 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)

76CHASSIS AND BODY
34
REPAIRREV: 05/99 LOWER FASCIA PANEL (HEATER DUCT)
ASSEMBLY
Service repair no - 76.46.05
Remove
1.Disconnect battery.
2.Remove steering wheel
See STEERING,
Repair, Steering wheel
.
3.Remove steering column nacelle
See
STEERING, Repair, Steering column nacelle
.
4.Remove instrument panel
See INSTRUMENTS,
Repair, instrument panel
.
5.Release heater cable at control lever
See
HEATING AND VENTILATION, Repair, Heater
control cable - air distribution
.
6.Remove 2 screws, withdraw switch panel from
lower fascia and disconnect switch multi-plugs.
7.Prise out Land Rover decal and remove screw
securing grab handle to crash pad.
8.Remove lower screw and lift grab handle from
lower fascia panel.
9.On RH drive vehicles only, remove screw
securing LH side of finisher to wiper motor cover.
10.Remove 4 screws and remove both demister
vents from crash pad.
11.Remove 3 screws securing crash pad to fascia
bulkhead.
12.Remove crash pad.
13.Remove radio, if fitted.
14.Remove 2 trim studs securing radio housing to
trim panel. Remove radio housing.

CHASSIS AND BODY
37
REPAIR REV: 05/9947.Connect leads and plugs to auxiliary switches
and clock.
48.Secure switch panel to lower fascia panel and
switch cover.
49.Position radio housing, if applicable, and feed
radio multi- plug, aerial and speaker leads from
switch cover to radio housing.
50.Secure radio housing to trim panel.
51.Fit radio connections and secure radio in
housing.
52.Fit crash pad to fascia bulkhead.
53.Fit demister vents in crash pad.
54.Fit grab handle to lower fascia panel and secure
to crash pad. Refit Land Rover decal.
55.Connect multi-plugs to rear screen, hazard and
interior lamp switches and fit switch panel to
fascia panel.
56.Fit heater control cable
See HEATING AND
VENTILATION, Repair, Heater control cable -
air distribution
.
57.Fit instrument panel
See INSTRUMENTS,
Repair, instrument panel
.
58.Fit steering column nacelle
See STEERING,
Repair, Steering column nacelle
.
59.Fit steering wheel
See STEERING, Repair,
Steering wheel
.
60.Reconnect battery.FRONT UNDERTRAY
Service repair no - 76.11.81 - Front undertray
Service repair no - 76.11.85 - Acoustic pad
Remove
1.Raise vehicle on ramp.
2.Position support under chassis front
crossmember.
3.Lower ramp to give clearance between axle and
undertray.
4.Remove 4 nuts, disconnect propeller shaft from
front axle, and move aside.
5.Remove 2 bolts securing undertray to chassis
front crossmember.
6.Remove nut securing undertray to bump stop
front fixing bolt on both sides.
7.Remove 2 bolts securing sides of undertray to
rear undertray.
8.Pull front undertray forwards to release flanges
from rear undertray.
9.Lower undertray to clear steering box etc. and
manouvre rearwards over axle.
10.Remove front undertray.
11.If necessary, remove 8 fasteners to release
acoustic pad from undertray.

HEATING AND VENTILATION
1
DESCRIPTION AND OPERATION HEATING AND VENTILATION SYSTEM
Description
The heating and ventilation system is standard on all
models. Air conditioning is an optional system which
provides fully integrated climate control for the vehicle
interior.The heater assembly, comprising a matrix housed in a
distribution unit and a variable speed blower motor, is
located on one side of the engine compartment and
attached directly to the fascia bulkhead.
The heating controls are positioned on the outside of
the instrument binnacle and cable linked to
mechanical flaps in the distribution unit.
Heater assembly
1.Heater distribution unit
2.Fixings, heater to fascia bulkhead
3.Heater matrix
4.Blower motor housing
5.Circlip, impeller to blower motor
6.Impeller
7.Resistor unit and harness connector8.Fixings, blower motor mounting plate
9.Mounting plate, blower motor
10.Blower motor
11.Fixings, blower motor to mounting bracket
12.Temperature flap, air flow to heater matrix
13.Air flap, air supply to plenum chamber (heater
duct)