1999 LAND ROVER DEFENDER engine

30MANIFOLD AND EXHAUST SYSTEM
4
REPAIR
7.Remove 4 bolts securing fuel cooler to inlet
manifold.
8.Remove 2 bolts and remove alternator support
bracket and disconnect fuel injector harness
multiplug.
9.Remove bolt securing engine dip stick tube to
camshaft carrier.
10.Remove dip stick tube and discard’O’ring.
11.Remove 2 nuts and 8 bolts securing inlet
manifold to cylinder head.
12.Disconnect multiplugs from turbocharger boost
control soleniod, ECT sensor, ambient air
pressure sensor, MAF sensor, and A/C
compressor.
NOTE: EU3 Model illustrated.
13.Remove 2 bolts securing harness to camshaft
carrier.
14.Release harness from engine and inlet manifold.
15.Remove inlet manifold and gasket.
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MANIFOLD AND EXHAUST SYSTEM
5
REPAIR Refit
16.Clean inlet manifold and mating face.
17.Fit new gasket.
18.Fit inlet manifold, and working from the centre
outwards, tighten nuts and bolts to25 Nm (18
lbf.ft).
19.Position harness to sensors and connect
multiplugs.
20.Tighten harness clip bolts to camshaft carrier to
10 Nm (7 lbf.ft).
21.Clean dip stick tube and fit new’O’ring.
22.Fit dip stick tube and tighten bolt to10 Nm (7
lbf.ft).
23.Connect glow plug leads.
24.Fit alternator support bracket and tighten bolts to
45 Nm (33 lbf.ft).
25.Position fuel cooler. Apply Loctite 242 to bolts
and tighten to18 Nm (13 lbf.ft).
26.Fit new gasket, position EGR valve and tighten
bolts to9 Nm (7 lbf.ft).
27.Connect multiplug to MAP sensor.
28.Fit cooling fan cowl.
29.Fit engine acoustic cover.
30.Reconnect battery negative lead.
31.Fit battery cover.GASKET - EXHAUST MANIFOLD
Service repair no - 30.15.12
Remove
1.Remove turbocharger.See FUEL SYSTEM,
Repair.
2. Models with A/C:Remove auxiliary drive belt.
See ELECTRICAL, Repair.
3.Remove 4 bolts securing compressor and move
to one side.
All Models
NOTE: EU3 Model illustrated.
4.Remove and discard 2 Allen screws securing
EGR pipe to exhaust manifold.
5.Remove 10 nuts securing exhaust manifold to
cylinder head.
6.Remove exhaust manifold and gasket.
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CLUTCH
5
DESCRIPTION AND OPERATION 1.Brake/clutch reservoir
2.Fluid supply pipe
3.Hydraulic feed pipe
4.Damper
5.Master cylinder
6.Piston
7.Clutch pedal
8.Primary driveshaft
9.Engine crankshaft
10.Drive plate
11.Dual mass flywheel
12.Ring gear
13.Leaf spring
14.Cover - pressure plate
15.Diaphragm
16.Release bearing
17.Ball spigot
18.Release bearing sleeve
19.Release lever
20.Slave cylinder
21.Piston
22.Bleed nipple
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33CLUTCH
6
DESCRIPTION AND OPERATION DESCRIPTION
General
The clutch system is a diaphragm type clutch operated by a hydraulic cylinder. The drive plate is of the rigid centre
type with no integral damping springs. The flywheel is of the dual mass type with damping springs integral with the
flywheel. The clutch requires no adjustment to compensate for wear.
Hydraulic Clutch
The hydraulic clutch comprises a master cylinder, slave cylinder and a hydraulic reservoir. The master and slave
cylinders are connected to each other hydraulically by plastic and metal pipes. The plastic section of the pipe
allows ease of pipe routing and also absorbs engine movements and vibrations.
The master cylinder comprises a body with a central bore. Two ports in the body connect the bore to the hydraulic
feed pipe to the slave cylinder and the fluid reservoir. The bore is also connected to a damper which prevents
engine pulses being transferred hydraulically to the clutch pedal. A piston is fitted in the bore and has an external
rod which is attached to the clutch pedal with a pin. Two coil springs on the clutch pedal reduce the effort required
to depress the pedal.
The master cylinder is mounted on the bulkhead and secured with two bolts. The cylinder is connected to the
shared brake/clutch reservoir on the brake servo by a braided connecting hose.
The slave cylinder is located on the left hand side of the gearbox housing and secured with two bolts. A heat
shield is fitted to protect the underside of the slave cylinder from heat generated from the exhaust system. The
slave cylinder comprises a cylinder with a piston and a rod. A port in the cylinder body provides the attachment for
the hydraulic feed pipe from the master cylinder. A second port is fitted witha bleed nipple used for removing air
from the hydraulic system after servicing. The piston rod locates on a clutch release lever located in the gearbox
housing. The rod is positively retained on the release lever with a clip.
Clutch Mechanism
The clutch mechanism comprises a flywheel, drive plate, pressure plate, release lever and a release bearing. The
clutch mechanism is fully enclosed at the rear of the engine by the gearbox housing.
A clutch release bearing sleeve is attached in the gearbox housing with two bolts and located on two dowels. A
spigot with a ball end is formed on the release bearing sleeve and provides a mounting and pivot point for the
clutch release lever. A dished pivot washer is located on the ball of the spigot. When the release lever is located
on the ball, the pivot washer seats against the rear face of the release lever. A spring clip is located on the lever
and the pivot washer and secures the lever on the spigot. A small bolt retains the spring clip in position.
The release lever is forked at its inner end and locates on the clutch release bearing carrier. The outer end of the
release lever has a nylon seat which locates the slave cylinder piston rod. A second nylon seat, positioned
centrally on the release lever, locates on the ball spigot of the release bearing sleeve and allows the release lever
to pivot freely around the ball.
The clutch release bearing locates on the clutch release lever and release bearing sleeve. The bearing is retained
on a carrier which has two flats to prevent the carrier rotating on the release lever. A clip retains the release lever
on the carrier. The bearing and carrier are not serviceable individually.
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33CLUTCH
8
DESCRIPTION AND OPERATION The dual mass flywheel is bolted on the rear of the crankshaft with eight bolts. A dowel on the crankshaft flange
ensures that the flywheel is correctly located. A ring gear is fitted on the outer diameter of the flywheel. The ring
gear is not serviceable. Thirty blind holes are drilled in the outer diameter of the flywheel adjacent to the ring gear.
The holes are positioned at 10°intervals with four 20°spaces. The holes are used by the crankshaft position
sensor for engine management.
The dual mass flywheel is used to insulate the gearbox from torsional and transient vibrations produced by the
engine. The flywheel comprises primary and secondary flywheels with the drive between the two transferred by a
torsional damper which comprises four coil springs. The springs are located in the inside diameter of the primary
flywheel. Two of the springs are of smaller diameter and fit inside the larger diameter springs.
The primary flywheel locates the ring gear and is attached to the crankshaft flange with eight bolts. The two pairs
of coil springs are located in a recess in the flywheel between two riveted retainers. A roller bearing is pressed
onto the central boss of the primary flywheel and retained with a riveted plate. The bearing provides the mounting
for the secondary flywheel.
The secondary flywheel comprises two parts; an outer flywheel which provides the friction surface for the clutch
drive plate and an inner drive plate which transfers the drive from the primary flywheel, via the coil springs, to the
outer flywheel. The two components of the secondary flywheel are secured to each other with rivets. The inner
drive plate is located between the two pairs of coil springs and can rotate on the ball bearing in either direction
against the combined compression force of the four coil springs. Under high torque loading conditions the
secondary flywheel can rotate in either direction up to 70°in relation to the primary flywheel.
The operating face of the secondary flywheel is machined to provide a smooth surface for the drive plate to
engage on. Three dowels and six studs and nuts provide for the location and attachment of the pressure plate.
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33CLUTCH
12
DESCRIPTION AND OPERATION OPERATION
Hydraulic operation
When the clutch pedal is depressed, the master cylinder piston is pushed into the master cylinder. The movement
of the piston pressurises the fluid in the master cylinder, forcing the pressurised fluid into the hydraulic feed pipe to
the slave cylinder. The hydraulic pressure is felt at the slave cylinder piston which moves under the hydraulic force
applied, pushing the clutch release lever via the piston rod.
When the clutch pedal is released, the force applied to the release lever by the fingers of the diaphragm, moves
the release lever, which pushes the slave cylinder piston into the cylinder. The displaced hydraulic fluid is pushed
up the hydraulic feed pipe and returns to the master cylinder.
Mechanism operation
When the clutch pedal is depressed, hydraulic pressure extends the piston and rod in the slave cylinder. The
extension of the piston pushes the rod against the outer end of the release lever which pivots around the ball
spigot.
The inner end of the release lever pivots towards the engine applying pressure to the release bearing. The release
bearing slides along the release bearing sleeve and pushes on the fingers of the diaphragm. The diaphragm
pivots around the chamfered rivets in the cover. As the diaphragm is deflected, it removes pressure from the
pressure plate. The pressure plate moves away from the drive plate assisted by the three leaf springs.
The removal of force from the pressure plate on the drive plate reduces the friction between the dual mass
flywheel, drive plate and pressure plate. The drive plate slips between the flywheel and the pressure plate
preventing rotary movement being transferred from the flywheel and pressure plate to the primary driveshaft.
When the clutch pedal is released, hydraulic force is removed from the piston in the slave cylinder. This allows the
fingers of the diaphragm to push the release bearing along the release bearing sleeve. The movement of the
release bearing moves the release lever which pivots on the ball spigot, pushing the piston and rod back into the
slave cylinder.
The removal of pressure from the release bearing on the diaphragm, causes the diaphragm to pivot around the
chamfered rivets in the cover. The force applied to the pressure plate from the diaphragm overcomes the force of
the leaf springs and the pressure plate moves towards the drive plate and flywheel.
The pressure plate applies pressure to the drive plate which is pushed against the flywheel. As the clutch pedal is
progressively released, the friction between the drive plate, flywheel and pressure plate increases. The increase in
friction transfers the rotary movement of the flywheel and pressure plate to the drive plate, which in turn starts to
rotate the primary drive shaft. When the clutch pedal is released fully, the force applied by the diaphragm to the
pressure plate forces the drive plate onto the flywheel with no slippage.
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37MANUAL GEARBOX
8
REPAIR
12.Remove 13 screws securing tunnel cover.
13.Release and remove tunnel cover.
14.Remove cooling fan.See COOLING SYSTEM,
Repair.
15.Remove air filter.See FUEL SYSTEM, Repair.
16.Remove 2 upper bolts securing clutch housing to
engine.
17.Remove bolt securing shim to clutch housing.
18.Release gearbox breather pipes from clips on
heater hose.
19.Remove starter motor.See ELECTRICAL,
Repair.
20.Remove exhaust front pipe.See MANIFOLD
AND EXHAUST SYSTEM, Repair.
21.Drain gearbox oil.See Adjustment.
22.Drain transfer gearbox oil.See
MAINTENANCE ,
23.Remove 3 nuts securing intermediate silencer to
tail pipe.
24.Release silencer from mounting rubbers, remove
silencer and discard gasket.
25.Mark front and rear propeller shaft to transfer
gearbox flanges for reassembly purposes.
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37MANUAL GEARBOX
10
REPAIR
34.Pull handbrake cable through heel board.
35.Disconnect multiplug from speed sensor and
release harness from clip on transfer gearbox.
36.Remove retaining nut and release battery earth
lead from transfer gearbox.
37.Release body harness clips from bracket on top
of transfer gearbox.
38.Lower gearbox jack sufficiently to allow transfer
gearbox lever to clear tunnel.
39.Disconnect 2 Lucars from differential lock switch,
multiplug from reverse light switch and multiplug
from low ratio detect switch - if fitted and release
multiplug from bracket.
40.Remove bolt and release earth leads from RH
side of transfer gearbox.
41.Support the weight of the engine.
42.Remove 6 bolts securing clutch housing to
engine.
43.With assistance, remove gearbox from engine.
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