1996 LAND ROVER DEFENDER engine

37MANUAL GEARBOX
6
REPAIRREV: 05/99 78.Position crossmember and locate over fixing
studs of LH and RH gearbox mounting rubbers.
79.Align crossmember and secure to chassis with 4
nuts and bolts on each side.
NOTE: Fit battery earth strap retaining clip
to LH top bolt.
80.Fit intermediate silencer.
See MANIFOLD AND
EXHAUST SYSTEM, Repair, Intermediate
pipe - 90
orSee MANIFOLD AND EXHAUST
SYSTEM, Repair, Intermediate pipe - 110/130
.
81.Fit front pipe to exhaust manifold
See
MANIFOLD AND EXHAUST SYSTEM, Repair,
Exhaust front pipe
.
82.Fit rear propeller shaft to transmission brake
drum. Tighten nuts to
47 Nm (33 lbf/ft).
83.Remove 3 bolts securing support cradle to
transmission and remove hoist.
84.Reconnect battery earth strap to transfer box
fixing.
85.Connect speedometer cable to transfer box and
secure with retaining clip.
86.Coat both sides of clutch slave clinder backing
plate with Hylomar P232M waterproof sealant.
87.Locate backing plate on slave cylinder.
88.Fit slave cylinder to bell housing, engaging
push-rod through centre of dust cover, and with
bleed screw uppermost. Tighten bolts to
25 Nm
(18 lbf/ft).
89.Fit front propeller shaft to transfer box. Tighten
nuts to
47 Nm (33 lbf/ft).
90.Refill main gearbox and transfer boxSee
MAINTENANCE , Under vehicle maintenance
.
91.Feed transmission brake cable through heel
board and ensure grommet is correctly located.
NOTE: Apply a soap solution to aid fitment
of cable.
92.Lower vehicle on ramp.
93.Fit ties to secure gearbox harness to
transmission breather pipes.
94.Fit breather pipe retaining clip to rear of engine.
95.Reconnect charge air hose at turbocharger.
96.Reconnect intake hose at induction manifold. If
EGR system is fitted, reconnect intake hose at
intercooler.
97.Reconnect radiator top hose at thermostat
housing.
98.Fit viscous fan unit
See COOLING SYSTEM,
Repair, Viscous coupling and fan
.
99.Reconnect battery.100.Refill cooling system
See COOLING SYSTEM,
Adjustment, Drain and refill cooling system
.
101.Connect cable clevis to handbrake lever and fit
handbrake gaiter.
102.Locate insulation pad over gear levers and fit to
tunnel cover.
103.Fit gear lever with gaiter to lower lever spline
and secure with retaining nut.
104.Fit gear lever cover.
105.Fit gear lever and transfer box lever knobs.
106.Fit gearbox cover carpet.
107.Check operation of handbrake and adjust as
necessary
See MAINTENANCE , Under
vehicle maintenance
.

41TRANSFER GEARBOX
2
FAULT DIAGNOSIS OIL LEAKS
Verify that oil leak is from transfer box and not main
gearbox before proceeding with checks.
Prior to road test
1.Check oil level in transfer box is correct.
2.Check tightness of level and drain plugs.
3.Check breather system for blockage. To validate
system pipe must be removed, inspected,
rectified as necessary and refitted.
4.Remove all traces of oil from exterior of transfer
box.
Take vehicle for short road test.
5.Identify source of leaks and rectify as follows.
Front or rear output seal leaking:-
1.Drain oil and remove leaking output flange.
2.Inspect seal track on flange for surface damage.
If damaged renew component.
3.Remove and discard oil seal.
4.Inspect seal locating bore and remove any sharp
edges which may damage new oil seal.
5.Fit new seal.
6.Fit output flange and all other parts.
7.Add oil to correct level into gearbox
See
SECTION 10, Maintenance, Under vehicle
maintenance
.
Cover plate sealant leaking.
1.Drain oil and remove leaking cover plate.
2.Remove all traces of joint sealant from both joint
faces.
3.Degrease all components and apply a thin film of
Hylomar sealant, to both joint faces.
4.Apply thread sealant to bolts which come into
contact with gearbox oil.
5.Refit cover plate.
CAUTION: Care must be taken not to
overtighten fixings.Leak between main and transfer gearboxes.
1.Site vehicle onto a ramp .
2.Select neutral in transfer box and select 4th gear
in main gearbox.
3.Run engine at 2000 rpm with clutch/drive
engaged.
4.Observe joint between main and transfer boxes.
5.If oil leak is found establish if it is gear oil.
6.If so, leak is originating from transfer box.
7.Check two inner (main/transfer) bolts are oil
tight, as these holes are tapped into main
transfer case.
8.Remove transfer box to inspect mainshaft collar
seal track condition, and front face of transfer
case for porosity
See Repair, Transfer
gearbox
.
9.If these areas require servicing, transfer gearbox
input seal must also be renewed.
CAUTION: Avoid damaging new seal lip
and ensure seal is fitted flush with
machined face. Also ensure new seal is
not damaged when refitting transfer gearbox.
10.If red ATF type oil is seen leaking during
workshop test, investigate main gearbox for
cause of leak.
Detent plug or electrical switch leaks.
1.Detent plugs and electrical switches do not
usually leak. It must be noted that they fit into
open tapped holes in transfer case and therefore
should be considered when looking for source of
leak.

STEERING
1
DESCRIPTION AND OPERATION DESCRIPTION
The steering system incorporates a compression joint
in the lower shaft and is designed to collapse on
impact. The mis-alignment of the upper steering
column with the steering box and the inclusion of two
universal joints, is also designed to prevent the
column moving toward the driver under frontal impact.
The steering box is located behind the first chassis
cross member and is connected to the road wheel
swivel housing by a drag link and track rod. A
hydraulic damper absorbs shocks in the steering,
caused by road wheel deflections when operating on
rough terrain.Power steering system
The power steering system comprises a hydraulic
pump which is belt driven from the engine and
supplied with fluid from a reservoir that also acts as a
cooler.
The steering box houses a self neutralizing rotary
valve which is part of the worm/valve assy and an
hydraulic piston/rack to assist the mechanical
operation. The rotary valve which is operated by
movement of the steering wheel, directs fluid pressure
to the appropriate side of the hydraulic piston/rack to
provide assistance.
Power steering system
1.Hydraulic pump
2.Fluid reservoir
3.Steering box
4.Upper column5.Universal joints
6.Lower shaft
7.Compression joint
8.Drag link

STEERING
5
DESCRIPTION AND OPERATION Pump and regulator valve operation
The pump which is belt driven from the engine is an
eccentric roller type and also houses the pressure
regulator and flow control valve. The pressure is
controlled by a spring loaded ball valve (3) which is
housed inside the flow control valve piston (4).
No demand for assistance High flow through box -
Low pressure
With no demand for assistance the rotary valve in the
steering box acts as a pressure relief valve, allowing
fluid (A) to flow freely through the steering box and
back to the reservoir and pump inlet (B).
No demand for assistance
1.Reservoir
2.Pump
3.Pressure control ball valve and spring
4.Flow control valve and spring
5.Press fit plug (ball bearing)
6.Restrictor
The ball plug (5) is pressed into the valve (4)
during manufacture and determines the opening
pressure of pressure relief valve (3).No flow, through box - High pressure
When the steering is turned, the rotary valve
effectively stops all fluid flow through the steering box,
thus causing an increase in pressure (A). This
increase in pressure is felt in the flow control valve
spring chamber where, at a pre-determined pressure
the relief valve (3) will open and allow the pressure to
escape. The fall in pressure in the flow control spring
chamber, allows the flow control valve to move to the
right, which in turn allows pump output (A) to escape
directly into the pump inlet (B).
Assistance demanded
As soon as the steering wheel is released after
making a turn, the system reverts to the condition
seen in J6292 and the road wheels are returned to the
straight ahead position by the mechanical steering
geometry.
In the event of any hydraulic failure, steering control,
though heavy, will be maintained through the
mechanical components in the steering box.

STEERING
1
FAULT DIAGNOSIS INSUFFICIENT POWER ASSISTANCE
1.Is fluid level correct?
YES - go to 3.
NO - Fill/bleed sytem
2.Is problem a leak?
YES - Diagnose
See Power Steering Fluid
Leaks
.
NO - continue
3.Is drive belt tension correct?
YES - go to 5.
NO - Is drive belt worn or contaminated with oil?
See ELECTRICAL, Repair, Auxiliary drive
belt
.
4.Is problem resolved?
YES - end
NO - continue
5.Carry out pressure test at idle and 1000 rev/min.
See Power Steering System - Test.
6.Is correct pressure achieved?
YES - steering box defective
Not at any speed go to 9.
Not at idle go to 7.
7.Is idle speed correct?
YES-Goto8.
NO - Correct idle speed -
See ENGINE TUNING
DATA, Information, 300 Tdi Engine
.
8.Is problem resolved?
YES - end
NO - go to 9.
9.Bypass steering box using adaptor tap
LRT-57-001
10.Is correct pressure obtained?
YES - defective steering box
NO - defective steering pump
CAUTION: Do not hold steering wheel on
full lock for more than 30 seconds in any
one minute to avoid overheating fluid and
possibly damaging seals.
NOTE: 1. Excessive pressure in the
system is almost always caused by a
faulty relief valve in the PAS pump.
NOTE: 2. Insufficient pressure in the
system is usually caused by low fluid level
or PAS pump drive belt slip, or one of the
following: PAS system leaks, faulty PAS pump
relief valve, fault in steering box valve and worm
assembly, leak at piston in steering box, worn
components in PAS pump or box.

57STEERING
2
FAULT DIAGNOSIS POWER STEERING SYSTEM - TEST
NOTE: If steering lacks power assistance.
Check pressure of hydraulic pump before
fitting new components. Use fault
diagnosis chart to assist in tracing faults.
A. Steering box.
B. Steering pump.
C. Existing hose, steering box to pump.
D. HoseLRT-57-030.
E. Test adaptorLRT-57-001.
F. Pressure gaugeLRT-57-005.
G. Thread adaptorLRT-57-004.
H. Thread adaptorLRT-57-022.Procedure
1.A hydraulic pressure gauge and test adaptor is
used to test power steering system. This gauge
is able to measure 140 kgf/cm
2. The maximum
power steering system pressure is 77 kgf/cm2.
2.Under certain fault conditions of the hydraulic
pump it is possible to obtain pressures up to 105
kgf/cm
2. It is important to realise that pressure on
gauge is same pressure being exerted upon
steering wheel. When testing, turn steering
wheel gradually while reading pressure gauge.
3.Check and maintain maximum fluid level of
reservoir.
4.Examine power steering units and connections
for leaks. All leaks must be rectified before
attempting to test the system.
5.Check steering pump drive belt tension and
renew belt if necessary,
See ELECTRICAL,
Repair, Auxiliary drive Belt
.
6.Assemble test equipment and fit to vehicle, as
shown in RR3959M.
7.Open tap of adaptor.
8.Bleed system, take care not to overload
pressure gauge.
9.With system in good condition, pressures should
be:
(A) Steering wheel held on full lock and engine
running at 1,000 rev/min, 70 to 77 kgf/cm
2.
(B) Steering wheel held on full lock and engine
idling, 28 kgf/cm
2.
Checks should be carried out on both full lock
positions.
CAUTION: Do not maintain this pressure
for more than 30 seconds in any one
minute to avoid overheating fluid and
possibly damaging seals.
10.Release steering wheel and with engine idling.
Pressure should read below 7 kgf/cm
2.
11.If pressures differ to those given a fault exists.
12.To determine if fault is steering box or pump.
Close adaptor tap for a maximum five seconds.
13.If gauge does not register specified pressure,
pump is faulty.
14.Fit a new pump, bleed system and repeat test. If
low pressure or a substantial imbalance exists,
fault is in steering box valve and worm
assembly.

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
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
.