shaft LAND ROVER DEFENDER 1999 Workshop Manual

19FUEL SYSTEM
8
DESCRIPTION AND OPERATION The injector push rod is operated from the rocker and cam assembly by a sprocket. The push rod is located in the
housing bore and retained in its extended position by a push rod return spring. The powerful spring ensures that
the push rod socket is always in contact with the rocking lever and the cam.
The lower part of the injector housing locates the spring loaded nozzle. The nozzle is retained in the housing by a
nozzle cap nut which is screwed onto the housing. The nozzle cap nut has four holes around its circumference
which connect to the fuel pump drilling in the cylinder head. The injector housing has ports located above the
nozzle cap nut which connect with the fuel delivery drilling in the cylinder head. An’O’ring seals the injector in the
machined location in the cylinder head and a copper washer seals the injector from the combustion chamber.
The injectors are supplied with pressurised fuel from the fuel pump via the pressure regulator housing and internal
drillings in the cylinder head. Each injector sprays fuel directly into the cylinder at approximately 1500 bar (22000
lbf.in) atomising the fuel and mixing it with intake air prior to combustion.
The camshaft and rocker arrangement depresses the push rod which pressurises the fuel within the injector.
When the injector is required to inject fuel into the cylinder, the ECM energises the solenoid which closes a valve
within the solenoid housing. The closure of the valve stops the fuel entering the return line to the pump, trapping it
in the injector. The compression of the fuel by the push rod causes rapid pressurisation of the fuel which lifts the
injector nozzle, forcing the fuel into the cylinder at high pressure. The ECM controls the injection timing by altering
the time at which the solenoid is energised and the injection period by controlling the period for which the solenoid
is energised.
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FUEL SYSTEM
11
DESCRIPTION AND OPERATION OPERATION
The low pressure stage of the fuel pump draws fuel from the swirl pot and pumps it into the fuel filter. The high
pressure stage of the fuel pump draws the fuel from the fuel filter and pumps it along the fuel feed pipe to the
cylinder head.
The fuel enters the cylinder head through a connection on the fuel pressure regulator housing and supplies each
injector with pressurised fuel. The fuel pressure regulator maintains the fuel pressure at the injectors at 4 bar (58
lbf.in) by returning excess fuel back to the fuel filter. The returned fuel passes through the fuel cooler in the engine
compartment before it passes to the fuel filter.
When the engine is running, each injector is operated by an overhead camshaft which depresses a push rod in
each injector at a timed interval. When the cam has depressed the push rod and the push rod is returning to its
extended position, fuel is drawn from the fuel supply drilling in the injector.
When the ECM determines that injection is required, the ECM transmits an electrical pulse which energises the
fast acting solenoid, closing the spill valve on the injector and locking fuel in the injector body. As the cam begins
to depress the push rod, the fuel in the injector is rapidly pressurised. When the pressure exceeds the nozzle
spring pressure, the nozzle opens and injects fuel at very high pressure into the cylinder.
When the ECM determines that the injection period should end, the solenoid is rapidly de-energised, opening the
spill valve on the injector and allowing fuel to pass into the return circuit.
The ECM controls the injection timing by altering the time at which the solenoid is energised, and the injection
period by controlling the period for which the solenoid is energised.
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FUEL SYSTEM
5
REPAIR TURBOCHARGER
Service repair no - 19.42.01
Remove
1.Remove battery cover.
2.Disconnect battery negative lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Release clip and disconnect breather hose from
camshaft cover.
5.Release clips and disconnect air flow meter from
air filter.
6.Disconnect multiplug from air flow meter.
7.Loosen clip screw and remove air inlet hose
from turbocharger.
8.Remove 3 bolts and remove exhaust manifold
heat shield.
9.Release clip and disconnect vacuum hose from
turbocharger wastegate.
10.Loosen clip screw and release air outlet hose
from turbocharger.
11.Remove turbocharger oil feed banjo bolt and
discard sealing washers.
12.Remove 3 nuts and release exhaust front pipe
from turbocharger and discard gasket.
13.Remove 3 nuts securing turbocharger to exhaust
manifold.
14.Loosen and unscrew turbocharger drain pipe
union from cylinder block.
15.Remove turbocharger and discard gasket.
16.Remove 2 bolts and remove turbocharger oil
drain pipe. Discard gasket.
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FUEL SYSTEM
7
REPAIR Refit
7.Clean air flow meter faces.
8.Fit new’O’ring to air filter.
9.Clean AAP sensor.
10.Using new’O’ring, fit AAP sensor and tighten
screws.
11.Position air filter assembly and secure in
grommets.
12.Position air flow meter and secure clips.
13.Position intake hose to air filter and tighten clip
screw.INJECTOR - SET
Service repair no - 19.60.12
Remove
1.Remove cooling fan.See COOLING SYSTEM,
Repair.
2.Remove rocker shaft.See ENGINE , Repair.
3.Position container to catch fuel spillage.
4.Disconnect quick release fuel hose connectors
from fuel connector block on cylinder head and
fuel cooler to drain fuel from cylinder head.
5.Disconnect 5 multiplugs from injectors.
6.Remove Torx bolt securing injector unit to
cylinder head.
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19FUEL SYSTEM
8
REPAIR
7.AssembleLRT-12-154/1to injector unit, screw in
slide hammer and remove injector.
8.UsingLRT-12-154/4,remove and discard
sealing washer.9.Remove and discard’O’ring seal.
10.Rotate engine to align camshaft lobes for access
of injector removal tool.
11.Carry out above procedure to remove the
remaining 4 injectors.
12.Rotate engine manually until each cylinder being
worked on is at TDC, and remove excess fuel
from piston bowl using a syringe.
Refit
13.Clean injector unit and mating faces in cylinder
head.
14.PositionLRT-12-154/2to injector units and fit
new’O’rings.
15.Fit new sealing washers to injector nozzles using
LRT-12-154/3.
16.Fit retainers to injectors, carefully fit injectors
ensuring retainer is located on its dowel and
tighten bolt to32 Nm (24 lbf.ft)
17.Connect multiplug to injector.
18.Repeat above operation for remaining injectors.
19.Connect fuel hoses.
20.New injectors must be programmed using
TestBook.
21.Fit rocker shaft.See ENGINE , Repair.
22.Fit cooling fan.See COOLING SYSTEM,
Repair.
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COOLING SYSTEM
5
DESCRIPTION AND OPERATION A - EU 3 Models
B- Pre EU3 Models
GENERAL
The cooling system used on the Diesel engine is a pressure relief by-pass type system which allows coolant to
circulate around the engine block and heater circuit when the thermostat is closed. With coolant not passing
through the by-pass or the radiator promotes faster heater warm-up which in turn improves passenger comfort.
A coolant pump is mounted on a casting behind the PAS pump and is driven from the PAS pump at crankshaft
speed by the auxiliary drive belt. The pump mounting casting connects with passages in the cylinder block and
pumps coolant from the radiator through the cylinder block.
A viscous fan is attached to an idler pulley at the front of the engine. The fan is attached to a threaded spigot on
the pulley with a right hand threaded nut. The fan draws air through the radiator to assist in cooling when the
vehicle is stationary. The fan rotational speed is controlled relative to the running temperature of the engine by a
thermostatic valve regulated by a bi-metallic coil.
The cooling system uses a 50/50 mix of anti-freeze and water.
Thermostat Housing
A plastic thermostat housing is located behind the radiator. The housing has three connections which locate the
radiator bottom hose, top hose and coolant pump feed pipe. The housing contains a wax element thermostat and
a spring loaded by-pass flow valve.
Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid
engine warm-up. The thermostat is closed at temperatures below approximately 82°C (179°F). When the coolant
temperature reaches approximately 82°C the thermostat starts to open and is fully open at approximately 96°C
(204°F). In this condition the full flow of coolant is directed through the radiator.
The thermostat is exposed to 90% hot coolant from the engine on one side and 10% cold coolant returning from
the radiator bottom hose on the other side.
Hot coolant from the engine passes from the by-pass pipe through four sensing holes in the flow valve into a tube
surrounding 90% of the thermostat sensitive area. Cold coolant returning from the radiator, cooled by the ambient
air, conducts through 10% of the thermostat sensitive area.
In cold ambient temperatures, the engine temperature is raised approximately 10°C (50°F) to compensate for the
heat loss of 10% exposure to the cold coolant returning from the radiator bottom hose.
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26COOLING SYSTEM
8
DESCRIPTION AND OPERATION Coolant Pump
1.Drive lugs (hidden)
2.Housing
3.’O’rings4.Cover
5.Feed hose connection
6.Impeller
The coolant pump is attached on the left hand side of the engine, behind the PAS pump. A cast housing, bolted to
the cylinder block provides a common attachment point for both pumps. The housing has galleries which connect
the coolant pump to the cylinder block and the oil cooler housing. The coolant pump comprises a shaft, a housing
and a cover.
The shaft, which passes through the alloy housing, is supported at each end by bearings. Seals at each end of the
shaft protect the bearings from the coolant. The forward end of the shaft has two lugs which engage with the PAS
pump shaft. The opposite end of the shaft is fitted with an impeller which draws coolant from the feed pipe and
circulates it through galleries in the cylinder block. The shaft is driven by the auxiliary drive belt at the same
rotational speed as the crankshaft by a pulley attached to the PAS pump.
The pump is sealed in the cast housing with two’O’rings. An outer cover is positioned over the pump and secured
with six bolts and sealed to the pump with an’O’ring. The cover provides the attachment for the feed pipe
connecting hose.
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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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MANIFOLD AND EXHAUST SYSTEM
1
REPAIR PIPE - EXHAUST - FRONT
Service repair no - 30.10.09
Remove
1.Remove engine acoustic cover.See ENGINE ,
Repair.
2.Release clip and disconnect breather hose from
camshaft cover.
3.Release clips and disconnect air flow meter from
air filter.
4.Disconnect multiplug from air flow meter.
5.Loosen clip screw and remove air inlet hose
from turbocharger.
6.Remove 3 bolts and remove exhaust manifold
heat shield.
7.Remove 3 nuts, release front pipe from
turbocharger and discard gasket.
8.Remove underbelly panel.See CHASSIS AND
BODY, Repair.
9.Remove 8 nuts and bolts and remove chassis
cross member.
10.Remove 2 nuts, release front pipe from
intermediate silencer.
11.Release front pipe from mounting rubber and
remove pipe.
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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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