wheel LAND ROVER DEFENDER 1999 Owner's Manual

12ENGINE
24
DESCRIPTION AND OPERATION Crankshaft
1.Front end to crankshaft sprocket
2.Oil supply cross-drillings
3.Main journals4.Big-end journals
5.Rear end to flywheel
The crankshaft is constructed from cast iron and is surface-hardened. The areas between the crankshaft journals
and the adjoining webs and balance weights are compressed using the cold roll process to form journal fillets.
Cross-drillings in the crankshaft between adjoining main and big-end bearings are used to divert lubrication oil to
the big-end bearings.
A torsional vibration damper is attached to the crankshaft pulley by three bolts.
The crankshaft is carried in six main bearings, with end-float being controlled by thrust washers positioned on both
sides of No. 3 main bearing.
Main bearings
There are six main bearings used to carry the crankshaft. Each of the bearing caps are of cast iron construction
and are attached to the cylinder block by two bolts.
The bearing shells are of the split cylindrical type. The upper half bearing shells are grooved to facilitate the supply
of lubrication oil to the bearings and fit into a recess in the underside of the cylinder block. The lower half bearing
shells are smooth and fit into the bearing caps.
Steel-backed, thrust washers are included at each side of No. 3 main bearing to control crankshaft end-float. One
side of each of the thrust washers is grooved, the grooved side of each of the thrust washers is fitted facing
outward from No. 3 main bearing.
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12ENGINE
4
REPAIR Refit
9.Position new crankshaft pulley to vice.
10.Remove 3 bolts and remove damper from
crankshaft pulley.
11.Using a lint free cloth, thoroughly clean oil seal
recess and the running surface on crankshaft
pulley.
12.Fit crankshaft pulley.
13.FitLRT-51-003to crankshaft pulley and secure
with 2 bolts.
14.Fit new crankshaft pulley bolt and tighten to460
Nm (340 lbf.ft).
NOTE: It is recommended that a torque
multiplier is used to tighten crankshaft
pulley bolt.
15.Remove 2 bolts and removeLRT-51-003from
crankshaft pulley.
16.Fit damper to crankshaft pulley, fit bolts and
tighten to80 Nm (60 lbf.ft).
17.Fit auxiliary drive belt.
18.Fit radiator.See COOLING SYSTEM, Repair.
19.Fit underbelly panel.See CHASSIS AND
BODY, Repair.OIL SEAL - CRANKSHAFT - REAR
Service repair no - 12.21.20
Remove
1.Remove flywheel.See this Section.
2.Remove sump gasket.See this Section.
3.Remove 5 bolts securing oil seal housing to
cylinder block.
4.Remove seal housing.
Refit
5.Clean seal housing mating face on cylinder
block.
6.Position seal protector,LRT-12-061over
crankshaft boss. Fit new seal and housing
assembly and remove toolLRT-12-061.
CAUTION: Oil seal must be fitted dry.
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ENGINE
5
REPAIR
7.Fit oil seal housing bolts and using sequence
shown, tighten to9 Nm (7 lbf.ft).
8.Fit sump gasket.See this Section.
9.Fit flywheel.See this Section.BEARING - SPIGOT - CRANKSHAFT
Service repair no - 12.21.45
Remove
1.Remove clutch assembly.See CLUTCH,
Repair.
2.Tap a thread in spigot bush to accommodate a
suitable impulse extractor.
3.Fit extractor to spigot bush.
4.Remove spigot bush from crankshaft.
Refit
5.Clean spigot bush and mating face in rear of
crankshaft.
6.Fit new spigot bush to crankshaft using a
suitable drift.
7.Fit clutch assembly.See CLUTCH, Repair.
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12ENGINE
22
REPAIR MOUNTING - GEARBOX - REAR - RH
Service repair no - 12.45.09
Remove
1.Remove LH rear gearbox mounting.See this
Section.
2.Remove 4 bolts securing mounting bracket to
transfer gearbox.
3.Remove 2 nuts, remove mounting and mounting
bracket.
Refit
4.Clean mounting and mating faces.
5.Position mounting and mounting bracket and
tighten nuts to48 Nm (35 lbf.ft)and bolts to85
Nm (63 lbf.ft).
6.Fit LH rear gearbox mounting.See this
Section.FLYWHEEL
Service repair no - 12.53.07
Remove
1.Remove clutch assembly.See CLUTCH,
Repair.
2.Remove and discard 8 bolts securing flywheel to
crankshaft and remove flywheel.
NOTE: Dowel located.
Refit
3.Clean flywheel and crankshaft mating face.
4.Position flywheel to crankshaft.
5.Fit new flywheel retaining bolts and tighten by
diagonal selection to:
Stage 1 -40 Nm (30 lbf.ft)
Stage 2 -Further 90°
CAUTION: Do not carry out stages 1 and 2
in one operation.
6.Fit clutch assembly.See CLUTCH, Repair.
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ENGINE
21
OVERHAUL
7.Using sequence shown, tighten sump bolts to25
Nm (18 lbf.ft).
8.Fit new centrifuge oil drain pipe gasket.
CAUTION: Gasket must be fitted dry.
9.Fit centrifuge oil drain pipe, fit bolts and tighten
to10 Nm (7 lbf.ft).SEAL - CRANKSHAFT - REAR
Service repair no - 12.21.20.01
Remove
1.Remove flywheel.See Repair.
2.Remove sump gasket.See this Section.
3.Remove 5 bolts securing crankshaft rear oil seal
housing to cylinder block.
4.Remove and discard crankshaft rear oil seal and
housing.
NOTE: Dowel located.
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12ENGINE
22
OVERHAUL Refit
1.Clean crankshaft rear oil seal housing mating
face on cylinder block, ensure bolt and dowel
holes are clean and dry. Remove all traces of oil
from oil seal running surface on crankshaft.
2.Position seal protectorLRT-12-061over
crankshaft boss. Fit new seal and housing,
removeLRT-12-061.
CAUTION: Oil seal must be fitted dry.
3.Fit oil seal housing bolts and using sequence
shown, tighten to9 Nm (7 lbf.ft).
4.Fit sump gasket.See this Section.
5.Fit flywheel.See Repair.STARTER RING GEAR
Service repair no - 12.53.19
Remove.
1.Remove flywheel.See Repair.
2.Drill a 3 mm (0.12 in) diameter hole at root of 2
teeth.
3.Apply a cold chisel to root of teeth, break ring
gear and remove from flywheel.
WARNING: SUITABLE EYE PROTECTION
MUST BE WORN.
Refit
1.Heat ring gear evenly to 350°C, indicated by
light blue colour.
2.Locate ring gear on flywheel and press on to
flange.
WARNING: Handle hot ring gear with care.
3.Allow ring gear to air cool.
4.Fit flywheel.See Repair.
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18ENGINE MANAGEMENT SYSTEM
12
DESCRIPTION AND OPERATION SENSOR - CRANKSHAFT SPEED AND
POSITION (CKP)
The CKP sensor is located in the transmission housing with its tip adjacent to the outer circumference of the
flywheel. The CKP sensor works on the variable reluctance principal, which sends a signal back to the ECM in the
form of an ac voltage.
The ECM uses the signal from the CKP sensor for the following functions.
To calculate engine speed.
To determine engine crank position.
To determine fuel injection timing.
The CKP sensor works as a Variable Reluctance Sensor (VRS). It uses an electromagnet and a target ring to
generate a signal. As the target ring passes the tip of the CKP sensor the magnetic field produced by the sensor is
cut and then re-instated. The ECM measures the signal as an ac voltage.
The outer circumference of the flywheel acts as the target ring for the sensor. The flywheel is divided into 36
segments, each of 10°. 31 segments have drilled holes and 5 segments are spaces. This equals 360°or one
engine revolution. The 5 spaces correspond to the TDC position of the 5 cylinders. This allows the ECM to control
fuel injection timing for each of the cylinders.
Inputs / Outputs
The two pins of the CKP sensor (C1068-1 & C1068-2) are both outputs. The ECM (C0158-13 & C0158-36)
processes the outputs of the sensor. To protect the integrity of the CKP sensor signal, an earth screen is used.
The ECM measures the outputs from the CKP sensor. The ECM (C0158-13) measures a positive signal on a
pink/black wire, and a negative signal (C0158-36) on a white/blue wire. The earth path for the sensor is via the
ECM (C0158-16).
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19FUEL SYSTEM
2
DESCRIPTION AND OPERATION DESCRIPTION
General
The fuel delivery system comprises a fuel tank, fuel pump, fuel pressure regulator, five injectors and a fuel filter.
The system is controlled by the ECM, which energises the fuel pump relay and controls the operation and timing
of each injector solenoid.
Unlike other Diesel engines, the Td5 has no injection pump. The diesel direct injection system receives fuel at
pressure from a two stage fuel pump located in the fuel tank. The system incorporates a fuel return to the fuel
pump, via a fuel cooler attached to the inlet manifold, and a fuel filter. A fuel pressure regulator is located in a
housing on the rear of the cylinder head. The regulator maintains the fuel delivered to the injectors at a constant
pressure and returns excess fuel back to the fuel filter and pump via the fuel cooler.
A fuel filter is positioned on the chassis longitudinal, below the RH rear wheel arch. The fuel feed and return to and
from the engine passes through the filter. The filter also incorporates a water sensor, which illuminates a warning
lamp in the instrument pack.
A moulded fuel tank is located at the rear underside of the vehicle between the chassis longitudinals. The tank
provides the attachment for the fuel pump and the fuel gauge sender unit, which is located inside the tank.
Fuel Tank and Breather
The fuel tank and breather system is a major part of the fuel delivery system. The fuel tank and breathers are
located at the rear of the vehicle between the chassis longitudinals.
Fuel Tank
The moulded fuel tank is made from High Molecular Weight (HMW) High Density Polyethylene (HDPE), and is
manufactured using a proportion of recycled plastic.
The tank is held in position by a metal cradle which is secured to the chassis cross members by four bolts, two
holding the front of the cradle in position, two holding the rear. The fuel tank has a useable capacity of 75 litres
(16.5 gallons).
An aperture in the top surface of the tank allows for the fitment of the fuel pump and fuel gauge sender unit, which
is retained with a locking ring. A reflective metallic covering is attached to the tank with three scrivets to shield the
tank from heat generated by the exhaust system.
Fuel Tank Breather System
The fuel tank filler tube incorporates a tank vent which allows air and fuel vapour displaced from the tank when
filling to vent to atmosphere via the filler neck.
A breather spout within the tank controls the tank’Full’height. When fuel covers the spout it prevents fuel vapour
and air from escaping from the tank. This causes the fuel to’back-up’in the filler tube and shuts off the filler gun.
The position of the spout ensures that when the filler gun shuts off, a vapour space of approximately 10% of the
tanks total capacity remains. The vapour space ensures that the Roll Over Value (ROV) is always above the fuel
level and vapour can escape and allow the tank to breathe.
The ROV is welded to the top surface of the tank. It is connected by a tube to the filler tube, which in turn is
connected to the atmospheric vent pipe. The ROV allows fuel vapour to pass through it during normal vehicle
operation. In the event of the vehicle being overturned the valve shuts off, sealing the tank and preventing fuel
from spilling from the atmospheric vent pipe.
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FUEL SYSTEM
9
DESCRIPTION AND OPERATION FUEL FILTER
1.Filter body
2.Nut
3.Bolt
4.Rubber washer
5.Water sensor6.Filter element
7.Air bleed valve
8.Air bleed connection
9.Copper washer
10.Connector
The fuel filter is mounted on the chassis longitudinal below the rear RH wheel arch. The filter has four quick
release coupling connections; low pressure feed from the fuel pump, low pressure return to the fuel pump, return
line from the fuel pressure regulator and a bleed line to the fuel pump. The fuel filter removes particulate matter
from the fuel and also separates water which accumulates at the bottom of the filter.
An air bleed valve is located in the bleed line connection. The valve comprises a restrictor and a membrane. The
restrictor has a small hole in its centre. This allows air and fuel to pass through the membrane. Air can pass
through the membrane, but once the membrane is wet with fuel, it will not allow further fuel to pass through.
The fuel filter has a replaceable screw-on cannister type filter element which is sealed to the filter body with rubber
seals. The lower part of the cannister has a screw connection for a water sensor. The filter has a flow rate of 180
litres/hour (47.6 US Gallons/hour).
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COOLING SYSTEM
9
DESCRIPTION AND OPERATION Viscous Fan
1.Idler pulley drive attachment
2.Fan blades3.Bi-metallic coil
4.Body
The viscous fan provides a means of controlling the speed of the fan relative to the operating temperature of the
engine. The fan rotation draws air through the radiator, reducing engine coolant temperatures when the vehicle is
stationary or moving slowly.
The viscous fan is attached to an idler pulley at the front of the engine which is driven at crankshaft speed by the
auxiliary drive belt. The fan is secured to the pulley by a right hand threaded nut. The nut is positively attached to
the fan spindle which is supported on bearings in the fan body. The viscous drive comprises a circular drive plate
attached to the spindle and driven from the idler pulley. The drive plate and body have interlocking annular
grooves with a small clearance which provides the drive when silicone fluid enters the fluid chamber. A bi-metallic
coil is fitted externally on the forward face of the body. The coil is connected to and operates a valve in the body.
The valve operates on a valve plate with ports that connect the reservoir to the fluid chamber. The valve plate also
has return ports which, when the valve is closed, scoop fluid from the fluid chamber and push it into the reservoir
under centrifugal force.
Silicone fluid is retained in a reservoir at the front of the body. When the engine is off and the fan is stationary, the
silicone fluid level stabilises between the reservoir and the fluid chamber. This will result in the fan operating when
the engine is started, but the drive will be removed quickly after the fan starts rotating and the fan will’freewheel’.
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