lock LAND ROVER DEFENDER 1999 Owners Manual

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
3
DESCRIPTION AND OPERATION FUEL PUMP AND FUEL GAUGE SENDER
1.Fuel burning heater feed pipe (not used)
2.Air bleed connection (natural)
3.HP feed connection (green)
4.LP feed connection (blue)
5.LP return connection (black)
6.Pump feed pipe.
7.Spring
8.Fuel gauge sender unit9.Swirl pot
10.Gauze filter
11.Fuel gauge sender float
12.Electrical connections
13.HP/LP two stage pump
14.Pump LP return pipe
15.Electrical connector
The fuel pump is a self priming, wet type, two stage pump, which is emersed in fuel in the tank. It operates at all
times when the ignition switch is in position’II’. If the engine is not started, the ECM will’time-out’after three
minutes and de-energise the fuel pump relay.
The fuel pump assembly is retained with a locking ring and sealed with a rubber seal. The locking ring requires a
special tool for removal and refitment. The fuel gauge sender is integral with the fuel pump. The sender is
submerged in the fuel and is operated by a float which moves with the fuel level in the tank.
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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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19FUEL SYSTEM
6
REPAIR Refit
17.Clean turbocharger and oil drain pipe mating
faces.
18.Using a NEW gasket, fit turbocharger drain pipe
and tighten bolts to10 Nm (7 lbf.ft).
19.Using a new gasket fit turbocharger to exhaust
manifold and tighten nuts to30 Nm (22 lbf. ft).
20.Position oil drain pipe to cylinder block and
tighten union.
21.Using new gasket, align exhaust front pipe and
tighten nuts to30 Nm (22 lbf.ft)
22.Fit banjo bolt to oil feed pipe using new sealing
washers and tighten to25 Nm (18 lbf.ft).
23.Position air outlet hose to turbocharger and
tighten clip screw.
24.Position and secure vacuum hose to
turbocharger wastegate.
25.Position exhaust manifold heat shield and
tighten M6 bolts to9 Nm (7 lbf.ft)and M8 bolt to
25 Nm (18 lbf.ft).
26.Position air inlet hose to turbocharger and
tighten clip screw.
27.Connect air flow meter to air filter and secure
clips.
28.Connect air flow meter multiplug.
29.Connect breather hose and secure clip.
30.Fit engine acoustic cover and secure with bolts.
31.Reconnect battery negative lead.
32.Fit battery cover.FILTER ASSEMBLY - AIR
Service repair no - 19.10.01
Remove
1.Loosen clip screw and release intake hose from
air filter.
2.Release 2 clips securing air flow meter.
3.Release air flow meter from air filter cover and
position aside.
4.Disconnect multiplug from AAP sensor.
5.Release air filter from 3 grommets, remove
assembly and discard’O’ring.
6.Remove 2 screws, remove AAP sensor and
discard’O’ring.
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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
10
REPAIR POTENTIOMETER - THROTTLE
Service repair no - 19.30.14
Remove
NOTE: The throttle potentiometer is an
integral part of the throttle pedal assembly
and must not be dismantled.
1.With assistance remove 2 nuts and bolts
securing throttle pedal to body.
2.Disconnect multiplug from throttle potentiometer
and remove throttle pedal.
Refit
NOTE: From Vin 607225 a three track
throttle potentiometer was fitted in place
of a two track potentiometer. Three track
potentiometers cannot be fitted to vehicles
previously fitted with two track potentiometers.
Two track potentiometers can be fitted to vehicles
previously fitted with three track potentiometers,
but TestBook must be used to configure the ECM.
3.Connect multiplug to throttle potentiometer.
4.Position throttle pedal assembly, tighten nuts
and bolts to25 Nm (18 lbf.ft).PUMP - FUEL
Service repair no - 19.45.08
Remove
1.Remove fuel tank.See this Section.
2.UsingLRT-19-009remove locking ring from fuel
pump housing.
3.Remove fuel pump from tank and discard
sealing ring.
Refit
4.Clean pump housing and mating face on fuel
tank.
5.Fit seal to pump housing.
6.Fit pump to fuel tank and secure with locking
ring.
7.Fit fuel tank.See this Section.
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FUEL SYSTEM
13
REPAIR
8.Disconnect vent hose from clips on rear chassis
member.
9.Support weight of fuel tank.
10.With assistance, lower fuel tank and remove
support plate.
11.Disconnect multiplug from fuel pump.
12.Noting their fitted position, disconnect 4 fuel
hoses from fuel pump.
13.Release clip and disconnect filler neck breather
from fuel tank.
14.With assistance, lower and remove fuel tank.
15.Remove 2 scrivits securing heat shield remove
heat shield.
16.Release clip securing breather hose to tank and
remove hose.
17.UsingLRT-19-009remove fuel pump locking
ring.
18.Remove fuel pump and discard sealing ring.
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19FUEL SYSTEM
14
REPAIR Refit
19.Clean fuel pump and mating face.
20.Fit new fuel pump sealing ring.
21.Fit fuel pump and secure with locking ring.
22.Fit breather hose and secure clip.
23.Position heat shield and secure with scrivits.
24.With assistance position fuel tank and support
plate.
25.Connect fuel hoses and multiplug to fuel pump.
26.Connect filler neck breather and secure clip.
27.Position vent hose and secure to chassis clips.
28.Raise fuel tank to its fitted position.
29.Fit nuts and bolts securing fuel tank and tighten
to25 Nm (18 lbf.ft).
30.Connect filler hose and secure clip.
Vehicles fitted with tow bar
31.Position support bar and tighten nuts and bolts.
32.Reconnect battery negative lead.
33.Fit battery cover.NECK - FUEL TANK FILLER
Service repair no - 19.55.07
Remove
1.Drain fuel tank.See Adjustment.
2.Loosen clip securing breather hose to fuel filler
neck and release hose.
3.Loosen clip securing fuel filler hose to neck and
release hose.
4.Remove screw and release earth lead from filler
neck.
5.Remove grommet securing filler neck to body.
6.Remove filler neck from body.
Refit
7.Fit filler neck to body.
8.Coat rubber grommet with soap solution.
9.Fit rubber grommet securing filler neck to body.
10.Connect earth lead and tighten screw.
11.Connect filler hose to neck and tighten clip.
12.Fit breather hose to filler neck and secure with
clip.
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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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