bonnet LAND ROVER DEFENDER 1996 Workshop Manual

10MAINTENANCE
2
MAINTENANCE BATTERY CONNECTIONS
NOTE: The vehicle may be fitted with an
alarm and immobilisation system using a
battery backed-up alarm sounder.
See
ELECTRICAL, Repair, Battery
Disconnect battery leads, clean and grease with
petroleum jelly, including battery terminals.
CHECK OPERATION OF DOOR SWITCHES
When a Vehicle Immobilisation and Alarm System is
fitted it is important that all door and bonnet switches
operate correctly, otherwise perimeter and interior
protection may not function if a door or the bonnet is
opened.VEHICLE EXTERIOR
CHECK/ADJUST HEADLAMP ALIGNMENT
Check/adjust headlamp alignment.
CHECK ROAD WHEELS AND TYRES
Check road wheels for damage.
Check tyres, including spare, for compliance with
manufacture's specificaton.
Check visually for cuts, lumps, bulges, uneven tread
wear and tread depth.
See INTRODUCTION,
Information, wheels and tyres
Check/adjust tyre pressures.See WHEELS AND
TYRES, Repair, Tyres pressures
INSPECT BRAKE PADS FOR WEAR, CALIPERS
FOR LEAKS AND CONDITION OF DISCS
Check thickness of brake pads, and renew if thickness
is less than 3,00 mm (0.12 in). Check brake pads for
oil contamination and fit a new set, if necessary,
See
BRAKES, Repair, front brake pads
orSee
BRAKES, Repair, rear brake pads
WARNING: When renewing brake pads, it
is essential that only genuine components
with correct grade of lining are used.
Always fit new pads as complete axle sets, NEVER
individually or as a single wheel set. Serious
consequences could result from out of balance
braking due to mixing of linings.
CHECK FRONT WHEEL ALIGNMENT
Use recognised wheel alignment equipment to carry
out this operation.
See STEERING, Adjustment,
front wheel alignment
CHECK OPERATION OF ALL DOORS/TAILGATE,
BONNET AND LOCKS
LUBRICATE ALL DOOR/TAILGATE HINGES, AND
DOOR CHECK/LOCK MECHANISMS

MAINTENANCE
3
MAINTENANCE UNDER BONNET MAINTENANCE
UNDER BONNET COMPONENTS
A - RH drive
1.Brake fluid reservoir
2.Clutch fluid reservoir
3.Air cleaner element
4.Engine breather filter
5.Oil filler cap
6.Oil level dipstick
7.Heater/air conditioning unit
8.Windscreen washer reservoir
9.Power steering pump reservoir10.Intercooler and hoses
11.Radiator filler plug
12.Radiator
13.Oil cooler
14.Fuel filter
15.Accelerator linkage
16.Expansion tank
17.Air cleaner dump valve

10MAINTENANCE
4
MAINTENANCE
UNDER BONNET COMPONENTS
B - LH drive
1.Brake fluid reservoir
2.Clutch fluid reservoir
3.Air cleaner element
4.Engine breather filter
5.Oil filler cap
6.Oil level dipstick
7.Heater/air conditioning unit
8.Windscreen washer reservoir
9.Power steering pump reservoir10.Intercooler and hoses
11.Radiator filler plug
12.Radiator
13.Oil cooler
14.Fuel filter
15.Accelerator linkage
16.Expansion tank
17.Air cleaner dump valve

ENGINE
3
REPAIR ENGINE
Service repair no - 12.41.01
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 and/or
integral access panels.
See CHASSIS AND BODY, Repair, Front
undertray
orSee CHASSIS AND BODY, Repair,
Rear undertray
CAUTION: Seal all exposed pipe ends
against ingress of dirt after disconnection.
1.Ensure vehicle is level and apply park brake.
2.Disconnect battery.
NOTE: The vehicle may be fitted with an
alarm and immobilisation system using a
battery backed-up alarm sounder.
See ELECTRICAL, Repair, battery
3.Remove bonnet.
4.Remove cable ties securing gearbox harness to
breather pipes.
5.Disconnect harness from diff lock and reverse
light switches.
6.Manouvre harness into engine bay.
7.Remove air cleaner.
See FUEL SYSTEM,
Repair, Air cleaner
8.Remove radiator assembly.See COOLING
SYSTEM, Repair, Radiator
If air conditioning is fitted the condenser will
have to be removed, compressor pipes and
heater matrix hoses disconnected.
See AIR CONDITIONING, Repair, Condenser
9.Remove rocker cover insulation.
10.Remove feed pipe/hose from turbo-charger and
intercooler.
11.Disconnect heater hoses from cylinder head and
heater rails.
12.Disconnect electrical feed plug at rear of cylinder
head.
13.Disconnect heater plug feed wire.

12ENGINE
6
REPAIR 42.Raise engine, and locate front engine mountings
to chassis.
43.Remove gearbox support and lower engine.
44.Tighten front engine mounting to chassis fixings
to
45 Nm (33 lbf/ft).
45.Release chains from engine lifting brackets and
remove hoist.
46.Connect oil cooler pipes to oil filter adaptor.
47.Fit vacuum hose to brake servo adaptor.
48.Secure fuel feed pipe in retaining clip on air
cleaner bracket.
49.Fit fuel lift pump pipes.
50.Connect feed and spill return pipes to injector
pump.
51.If fitted, reconnect hand throttle cable to
mounting bracket and injector pump.
52.Fit outer cable adjusting nut into injector pump
mounting bracket.
53.Fit inner throttle cable to injector pump and
secure with clevis and split pin.
54.Secure bleed hose in retaining clips on front
timing cover.
55.Fit bleed hose to thermostat housing.
56.Connect inlet and outlet hoses to power steering
pump.
57.Fit down pipe to exhaust manifold and secure
with 3 nuts.
58.Connect starter motor battery and fuse box
leads.
59.If fitted, connect EGR valve multi-plug and
vacuum pipe.
60.Secure breather pipe clip to cylinder head.
61.Connect engine harness multi-plug.
62.Fit heater plug feed wire.
63.Connect electrical feed plug at rear of cylinder
head.
64.Fit heater hoses to cylinder head and heater
rails.
65.Fit feed pipe/hose to turbo-charger and
intercooler.
66.Fit rocker cover insulation.
67.Fit radiator assembly.
See COOLING SYSTEM,
Repair, Radiator
If applicable, fit air
conditioning condenser, compressor pipes and
heater matrix hoses.
See AIR CONDITIONING,
Repair, Condenser
68.Fit bonnet.
69.Reconnect battery.CRANKSHAFT PULLEY
Service repair no - 12.21.01
Remove
1.Disconnect battery.
2.Drain coolant.
See COOLING SYSTEM,
Repair, Drain and refill cooling system
3.Remove top hose from radiator.
4.Remove intercooler to induction manifold hose.
5.Remove viscous coupling and fan.
See
COOLING SYSTEM, Repair, Viscous
coupling and fan
6.Remove fan cowl.See COOLING SYSTEM,
Repair, Fan cowl
7.Remove drive belt.See ELECTRICAL, Repair,
Auxiliary drive belt
8.Fit crankshaft pulley retainerLRT-12-080and
secure with 4 bolts.
9.Remove crankshaft pulley retaining bolt
anti-clockwise using socket and suitable long
bar.
10.Remove pulley retainer.
11.Remove pulley, if necessary using extractor
LRT-12-049with thrust pad fromLRT-12-031.

12ENGINE
20
REPAIR OIL FILTER HEAD GASKET
Service repair no - 12.60.03
Remove
1.Clean filter head adaptor.
2.Disconnect oil cooler pipes and plug to prevent
ingress of dirt.
3.Disconnect oil pressure switch lead.
4.Remove 4 bolts and withdraw filter head,
complete with gasket.
5.Clean mating faces of filter head and cylinder
block.
6.Fit head with new gasket.
7.Tighten bolts to
45 Nm (33 lbf/ft).
8.Reconnect oil pressure switch lead.
9.Reconnect oil cooler pipes.CYLINDER HEAD GASKET
Service repair no - 12.29.02
Remove
1.Disconnect battery
2.Remove bonnet.
3.Drain coolant.
See COOLING SYSTEM,
Repair, Drain and refill cooling system
4.Remove air cleaner.See FUEL SYSTEM,
Repair, Air cleaner
5.Detach crankcase ventilation valve and side
breather hose from rocker cover and move to
one side.
6.Remove fuel injectors and pipes.
See FUEL
SYSTEM, Repair, Fuel injectors
7.Remove heater plugs.See FUEL SYSTEM,
Repair, Heater plugs
8.Disconnect radiator top hose from thermostat.
9.Disconnect bleed hose at thermostat.
10.Disconnect water pump hose at thermostat.
11.Disconnect water temperature sensor lead.

ENGINE
23
REPAIR
43.Check and adjust valve clearances.
See Adjustment, Valve clearances - check
and adjust
44.Fit rocker cover, ensuring oil seal is satisfactory
for continued use, and renew if necessary.
45.Secure rocker cover with special seal washers
and nuts. Tighten to
10 Nm (7 lbf/ft).
46.Fit rear engine lifting bracket, securing breather
pipe and multi-plug retaining clips. Tighten fixing
bolts to
25 Nm (18 lbf/ft).
47.Fit engine harness bracket to cylinder head.
48.Secure air cleaner mounting bracket to support
strut.
49.Connect heater hose to rear of cylinder head.
50.Position heater rail and connect hose from water
pump.
51.Fit exhaust manifold and turbocharger assembly.
See MANIFOLD AND EXHAUST SYSTEM,
Repair, Exhaust manifold
52.Fit induction manifold.See MANIFOLD AND
EXHAUST SYSTEM, Repair, Induction
manifold
53.Connect water temperature sensor lead.
54.Connect water pump hose at thermostat.
55.Fit bleed hose at thermostat.
56.Connect radiator top hose at thermostat.
57.Fit heater plugs.
See FUEL SYSTEM, Repair,
Heater plugs
58.Fit fuel injectors.See FUEL SYSTEM, Repair,
Fuel injectors
59.Fit crankcase ventilation valve and side breather
hose.
60.Fit air cleaner.
See FUEL SYSTEM, Repair,
Air cleaner
61.Refill cooling system.See COOLING SYSTEM,
Repair, Drain and refill cooling system
62.Fit bonnet.
63.Reconnect battery.OIL PUMP
Service repair no - 12.60.26
Remove
1.Remove engine front cover.
See Front cover
gasket
2.Remove 7 screws and release oil pump retaining
plate from engine front cover.
3.Mark oil pump inner gear rotor, outer gear rotor
and front cover housing for reassembly.
4.Check for rotor clearances:
Outer rotor to housing, 0,025 - 0,075 mm (0.010
- 0.030 in).
Inner rotor to outer rotor, 0,025 - 0,075 mm
(0.010 - 0.030 in).
Rotor end float, 0,026 - 0,135 mm (0.010 - 0.054
in).
5.Remove inner and outer rotors.
6.Check condition of oil pump components.
NOTE: If the oil pump seating in the front
cover or retaining plate is badly worn,
pitted or scored, a new front cover must
be fitted.
See Front cover gasket
Always renew oil pump rotors as a pair.
7.Clean sealant from pump retaining plate and
front cover.

FUEL SYSTEM
9
DESCRIPTION AND OPERATION OPERATION
Diesel engines operate by compression ignition. The
rapid compression of air in the cylinder during the
compression cycle heats the air and when fuel is
injected into the heated air, it ignites instantaneously.
During cold tarting, automatically controlled heater
plugs assist in raising the temperature of the
compressed air to ignition point.
A cold start advance unit advances the injection timing
to further assist starting. Idle quality is improved by
the high idle setting.
The engine is supplied with pre-compressed air by a
single stage turbocharger.
Exhaust gases passing over a turbine cause it to
rotate, driving a compressor mounted on the turbine
shaft. Air drawn from the cold air intake passes, via
the air cleaner, to the turbocharger where it is
compressed. Compression in the turbocharger warms
up the air considerably, so that it expands. As a result
the air mass per cylinder is reduced, having a
negative effect on power output. By fitting a charge-air
intercooler, located on the LH side of the radiator, the
air is cooled before reaching the cylinders. This
increases power output through increased mass of
oxygen in the combustion process, as well as
maximising engine durability, through maintaining
lower piston and head temperatures.
Fuel is drawn from the tank by a mechanical lift pump
and passes to the injection pump via a filter. In
addition to removing particle contamination from the
fuel, the filter incorporates a water separator, which
removes and stores water.
The sedimentor/s, when fitted, is located adjacent to
the fuel tank/s and separates contamination and water
particles in the fuel before reaching the fuel lift pump.
The injection pump meters a precisely timed, exact
quantity of fuel to the injectors in response to throttle
variations, injection timing varying with engine speed.
Any excess fuel delivered to the injection pump is
passed back to the tank via the spill return line.
Fuel is injected in a finely atomised form into the main
combustion chamber, the burning fuel expands
rapidly, creating extreme turbulence which mixes the
burning fuel thoroughly with the compressed air,
providing complete combustion.Cold Starting is assisted by heater plugs, a cold start
advance unit and a high idle setting.
Heater plugs
Heater plug operation is controlled by a timer unit,
start relay and resistor. When the ignition is turned on
the timer unit is energised, the heater plugs start to
operate and a warning light on the dashboard
illuminates, remaining on until the heater plugs are
automatically switched off.
The length of time the heater plugs will operate is
dependent on under bonnet temperature, which is
monitored by a sensor located in the timer unit.
Starting the engine results in the power supply to the
heater plugs passing through the resistor, which
reduces their operating temperature. The heater plugs
are cut out either by the temperature sensor in the
timer, or by a microswitch on the injection pump which
operates when the throttle is depressed.
Cold start advance
The cold start advance unit is connected to the engine
cooling system via hoses. It contains a temperature
sensitive element which is retracted when cold and
pulls the advance lever, via cable, towards the rear of
the pump against spring pressure. As coolant
temperature rises, the cold start element expands
releasing tension on the cable and allowing spring
pressure to move the advance lever forwards.
Exhaust gas recirculation (EGR), when fitted
Operation of the EGR system is dependent on the
following:
·Engine temperature - must be between 20°C and
100°C approx.
·Engine speed - must be between 630 and 2850
rev/min.
·Engine load - calculated by throttle position
sensor.
·EGR valve lift position.
·Duration of engine idling.

19FUEL SYSTEM
12
REPAIR HEATER PLUG CONTROL UNIT
Service repair no - 19.60.33
Remove
1.Disconnect battery.
2.Remove screw securing control unit to bulkhead.
3.Disconnect multi-plug and release control unit.
Refit
4.Fit harness multi-plug to control unit.
5.Secure control unit to bulkhead.
6.Reconnect battery.AIR CLEANER
Service repair no - 19.10.01
Remove
1.Slacken hose clip and detach outlet hose.
2.Release clips and open air cleaner retaining
straps.
3.Lift up air cleaner, slacken hose clip and detach
inlet hose.
4.Remove air cleaner.
Refit
5.Position air cleaner and connect inlet hose.
6.Close air cleaner retaining straps and secure
lock clips.
7.Connect outlet hose.
NOTE: If an EGR fuel system is fitted,
ensure the modulator valve vacuum spill
pipe is secure in the outlet hose.
AIR CLEANER ELEMENT
Service repair no - 19.10.10
For remove and refit procedure.
See SECTION 10,
Maintenance, Under bonnet maintenance

19FUEL SYSTEM
14
REPAIR TURBOCHARGER INLET HOSE
Service repair no - 19.42.11
Remove
1.Disconnect battery.
2.Slacken retaining clip and disconnect intake
hose from turbocharger.
3.Slacken retaining clip and disconnect hose from
air cleaner.
4.If fitted, disconnect EGR modulator valve
vacuum spill pipe from inlet hose.
5.Slacken retaining clip and disconnect breather
valve hose from inlet hose.
6.Remove inlet hose.
Refit
7.Fit inlet hose to air cleaner.
8.Fit cyclone breather hose to inlet hose.
9.If applicable, fit vacuum spill pipe to inlet hose.
10.Fit inlet hose to turbocharger.
11.Reconnect battery.TURBOCHARGER OIL FEED PIPE
Service repair no - 19.42.14
Remove
1.Disconnect battery.
2.Remove exhaust front pipe.
See MANIFOLD
AND EXHAUST SYSTEM, Repair, Exhaust
front pipe
3.Remove banjo bolt securing oil feed pipe to
turbocharger and discard 2 joint sealing
washers.
4.Unscrew union and remove feed pipe from
cylinder block.
5.Plug connections to prevent ingress of dirt.
Refit
6.Using new joint washer, fit oil feed pipe to
cylinder block. Tighten union connector to
25
Nm (18 lbf/ft).
7.Fit a new joint washer to both sides of banjo and
secure feed pipe to turbocharger. Tighten banjo
bolt to
20 Nm (15 lbf/ft).
8.Fit exhaust front pipe.See MANIFOLD AND
EXHAUST SYSTEM, Repair, Exhaust front
pipe
9.Check/top-up engine oil level.See SECTION
10, Maintenance, Under bonnet maintenance
10.Reconnect battery.