Land Rover Defender 90 Workshop 2nd Edition Nas Rover Manual

							19FUEL SYSTEM
22
REPAIR RAM HOUSING
Service repair no - 19.70.04
Remove
1.Disconnect battery negative lead.
2.Remove plenum chamber.
See plenum
chamber
3.Disconnect 3 hoses from ram housing.
4.Remove 6 bolts securing ram housing to inlet
manifold.
5.Using a suitable lever and a block of wood,
release ram housing from inlet manifold.
Remove ram housing.
CAUTION: Do not use a mallet to break
sealant joint with inlet manifold.
6.Place a protective cover over inlet bores to
prevent ingress of dirt.Refit
7.Clean mating faces of inlet manifold and ram
housing.
8.Apply Hylomar sealant to inlet manifold face.
9.Fit ram housing to inlet manifold.
NOTE: The ram housing can be fitted the
wrong way round. Ensure fuel pressure
regulator hose connection is on correct
side when refitting.
10.Tighten ram housing bolts, working from 2 centre
bolts, diagonally towards 4 outer bolts to
24 Nm,
18 lbf ft.
11.Connect hoses to ram housing.
12.Fit plenum chamber.
See plenum chamber;
Refit
13.Reconnect battery negative lead. 
						

							SFI
23
REPAIR WHEEL SPEED SENSOR - FRONT
Service repair no - 19.80.01
Remove
CAUTION: If a sensor is removed for any
reason, a NEW sensor bush and seal must
be fitted.
1.Disconnect battery negative lead.
2.Release wheel speed sensor multiplug from clip
on inner wing [fender] and disconnect.
3.Raise vehicle on 4 post ramp.
4.Release cable ties securing sensor harness to
chassis and front axle.
5.Clean area around sensor to prevent possible
ingress of dirt.
6.Using a suitable lever, release sensor from
mounting bush.
7.Remove sensor.
8.Position container to collect any brake fluid.
9.Clamp flexible brake hose to caliper.
10.Using 2 spanners, loosen brake pipe to hose
union and disconnect.
CAUTION: Do not allow brake fluid to
contact paint finished surfaces as paint
may be damaged. If spilled, remove fluid
and clean area with clean warm water.
11.Remove nut securing brake pipe to mounting
bracket.
12.Release brake hose from mounting bracket.
13.Remove 2 bolts securing bush retaining plate to
top of hub.
14.Release retaining plate from mud shield and
remove.
15.Remove and discard seal and bush from hub.
Refit
16.Ensure sensor bush and seal mating faces are
clean.
17.Fit sensor bush and seal to hub.
18.Fit retaining plate to hub and secure with bolts.
CAUTION: Apply Loctite 270 to retaining
plate bolts. 
						

							19FUEL SYSTEM
24
REPAIR 19.Position brake hose to mounting bracket and
secure with nut.
20.Connect brake pipe to hose and, using 2
spanners, tighten union.
21.Remove clamp from brake hose.
22.Ensure sensor body is clean and coat with EP
90 oil.
23.Fit sensor through bush until it contacts the
reluctor ring. The sensor will be knocked-back
to the correct position when the vehicle is driven.
24.Route sensor lead up through engine
compartment and secure cable ties.
25.Lower vehicle.
26.Connect sensor multiplug and secure to clip.
27.Reconnect battery negative lead.
28.Bleed brake system.
See BRAKES, Repair,
brake system bleed
WHEEL SPEED SENSOR - REAR
Service repair no - 19.80.02
Remove
CAUTION: If a sensor is removed for any
reason, a NEW sensor bush and seal must
be fitted.
1.Disconnect battery negative lead.
2.Raise rear of vehicle.
WARNING: Support on safety stands.
3.Remove both rear road wheels.
4.Disconnect sensor multiplugs at RH side of
chassis.
5.Release cable ties securing sensor harness to
rear suspension and axles. 
						

							SFI
25
REPAIR
6.Release sensor harness from clips on rear axle.
7.Remove 6 bolts, 3 each side, securing rear
wheel brake caliper mud shields.
8.Remove mud shields and clear area around
sensor to prevent possible ingress of dirt.
9.Using a suitable lever, release sensors from
mounting bushes.
10.Remove sensors.
11.Remove and discard sensor bushes.Refit
12.Ensure NEW sensor bushes and housings are
clean, then fit bushes.
13.Ensure sensor bodies are clean and lightly coat
with EP 90 lubricant.
14.Fit sensors through bushes until they contact the
reluctor ring. The sensors will be knocked-back
to the correct position when the vehicle is driven.
15.Secure sensor harness to rear axle clips.
16.Secure sensor harness to rear suspension and
axle with cable ties.
17.Connect sensor harness multiplugs.
18.Position rear brake caliper mud shields and
secure with bolts.
19.Fit rear road wheels.
20.Remove stand(s) and lower vehicle.
21.Reconnect battery negative lead. 
						

							19FUEL SYSTEM
26
REPAIR ECU - ROUGH ROAD DETECTION
Service repair no - 19.80.03
Remove
1.Disconnect battery negative lead.
2.Release front edge of passenger seat cushion
and remove cushion.
3.Release clip and remove ECU cover plate.
4.Remove 2 bolts securing ECU to mounting
bracket and collect nuts.
5.Remove ECU from mounting bracket and
disconnect multiplug.
6.Remove ECU.Refit
7.Fit ECU, connect multiplug and position to
mounting bracket.
8.Secure ECU mounting bracket with nuts and
bolts.
9.Fit ECU cover plate and secure with clip.
10.Position rear edge of passenger seat cushion to
seat frame and secure front edge to clips.
11.Reconnect battery negative lead. 
						

							SFI
1
SPECIFICATIONS, TORQUE TORQUE SETTNGS
Nm lbf ft
Intake air temperature (IAT) sensor 8................................. 6
Crank position sensor 8...................................................... 6
Coolant temperature sensor 20............................................. 15
Fuel filter 30.......................................................................... 20
Fuel pressure regulator 10.................................................... 7
Coil bracket 8...................................................................... 6
Fuel feed pipe 16.................................................................. 12
Ram housing to manifold 24................................................. 18
Fuel temperature sensor 17.................................................. 13
Throttle position sensor 2.................................................... 1.5
Knock sensor 16................................................................... 12
Idle air control valve 2......................................................... 1.5
Water jacket 13..................................................................... 10
Throttle bracket 8................................................................ 6
Plenum chamber 24.............................................................. 18
Inlet manifold 38.................................................................... 28
Camshaft position sensor 8................................................. 6
Heated oxygen sensors 20................................................... 15
Fuel pump locking ring 48..................................................... 35 
						

							COOLING SYSTEM
1
DESCRIPTION AND OPERATION ENGINE COOLING
Description
The V8i engine uses a pressurised cooling system
and cross flow radiator which is supplied from a
separate expansion tank. The coolant radiator also
incorporates a section at the side for cooling the
engine oil. The transmission fluid cooler is mounted
below the radiator.The belt driven viscous fan and centrifugal water
pump is located in the engine front cover with ports for
circulation of coolant to both banks of cylinders and
cylinder heads. Coolant returns to the top of the
radiator via ports in the inlet manifold where the
thermostat is mounted horizontally.
Coolant also circulates through the vehicle heating
system and is used to heat air entering the inlet
manifold plenum chamber.
Coolant circulation (engine hot)
1. Cross flow radiator
2. Expansion tank
3. Viscous fan and water pump
4. Heater pipes
5. Thermostat
6. Plenum chamber connection 
						

							26COOLING SYSTEM
2
DESCRIPTION AND OPERATION COOLANT CIRCULATION
Operation
When the engine is started from cold the thermostat
prevents any coolant circulation through the radiator
by closing off the top hose. During the engine warm
up period, the water pump, pumps coolant around the
cylinders to the rear of the cylinder block along the
main galleries in both cylinder banks. At the rear of
the cylinder block the coolant rises through a large
port in each cylinder head/block joint face, and then
flows forward to connect with ports at the front of the
inlet manifold. From the manifold the coolant is carried
by an external pipe to the heater unit and from the
heater through another external pipe to the pump
inlet.The coolant circulation through the cylinder block and
heads, does not change when normal running
temperature is reached and the thermostat opens. But
with the thermostat open, coolant also flows through
the top hose to the radiator where it is cooled and
drawn back into the pump via the bottom hose.
Throttle housing heating
The base of the throttle housing is heated by a flow of
coolant from the inlet manifold which returns through a
long hose, to the top right corner of the radiator. The
throttle housing is heated to prevent throttle disc icing. 
						

							COOLING SYSTEM
3
DESCRIPTION AND OPERATION VISCOUS FAN
Description
The viscous drive unit for the engine cooling fan,
provides a means of controlling the speed of the fan
relative to the running temperature of the engine. The
viscous unit is a type of fluid coupling, which drives
the fan blades by means of silicone fluid.
1.Input (drive) member
2.Output (driven) member
3.Sensing mechanism (bi-metal coil)
The fan drive has to be engaged only periodically,
between 5% and 10%, during normal operating
conditions, because the engine is cooled by ram air
for most of the time.Operation
To engage and disengage the fan drive the bi-metal
coil senses air temperature behind the radiator. When
a pre-determined temperature is reached, the coil
opens a valve (5) which allows fluid to enter the drive
area and, due to centrifugal force, circulates to the
annular drive area.
There are two sets of annular grooves (3), one in the
drive clutch and the other in the drive body, a specific
clearance being provided between the two sets of
grooves.
Viscous unit disengaged (engine at normal
running temperature)
1.Input (drive) member
2.Output (driven) member
3.Running clearance
4.Pump plate
5.Valve (closed)
6.Sensing mechanism (bi-metal coil)
7.Fluid seal
8.Bearing, input member
9.Fluid chamber
10.Fluid reservoir 
						

							26COOLING SYSTEM
4
DESCRIPTION AND OPERATION When this clearance is filled with viscous fluid, a
shearing action, caused by the speed differential
between the two drive components, transmits torque
to the fan. The fluid is thrown to the outside of the unit
by centrifugal force from where it is recirculated to the
reservoir (10) via the pump plate (4) adjacent to the
drive member.
If the engine speed is increased the amount of slip will
also increase to limit the maximum fan speed.
When the air temperature from the radiator drops
sufficiently, the bi-metal coil closes the valve and
prevents fluid entering the drive area. The fluid that is
in the drive area will gradually pump out into the
reservoir (10) and the fan will return to an idle
condition.
Viscous unit engaged (hot running temperature)
Bi-metal coil (6) expanded, valve (5) open.