1999 LAND ROVER DEFENDER relay

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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19FUEL SYSTEM
4
DESCRIPTION AND OPERATION Fuel Pump
The fuel pump assembly comprises a top cover which locates the electrical connector, and four fuel pipe
couplings. The top cover is attached to a plastic cup shaped housing and retained on three sliding clips. Two coil
springs are located between the cover and the housing and ensure that the fuel pump remains seated positively at
the bottom of the tank when installed.
The housing locates the two stage fuel pump and also the fuel gauge sender unit. The lower part of the housing is
the swirl pot which maintains a constant level of fuel at the fuel pick-up. A coarse filter is located in the base of the
housing and prevents the ingress of contaminants into the pump and the fuel system from the fuel being drawn
into the pump. A fine filter is located in the intake to the low pressure stage to protect the pump from
contaminants. Flexible pipes connect the couplings on the top cover to the pump.
A non-return valve is located in the base of the housing. When the fuel tank is full, fuel pressure keeps the valve
lifted from its seat, allowing fuel to flow into the swirl pot. As the tank level reduces, the fuel pressure in the tank
reduces causing the valve to close. When the valve is closed, fuel is retained in the swirl pot, ensuring that the
swirl pot remains full and maintains a constant supply to the fuel pump.
The two stage pump comprises a high and low pressure stage. The low pressure stage draws fuel from the swirl
pot through a filter. The low pressure stage pumps fluid at a pressure of 0.75 bar (10.9 lbf.in) and a flow of 30
litres/hour (8 US Gallons/hour) to the fuel filter. A proportion of the fuel from the low pressure stage also passes,
via a restrictor, through a jet pump which keeps fuel circulating in the swirl pot. The high pressure stage draws the
low pressure fuel from the fuel filter and pressurises it to a pressure of 4.0 bar (58 lbf.in). The pressurised fuel is
then passed from the pump to the injectors at a flow of 180 litres/hour (47.6 US Gallons/hour). A fuel pressure
regulator is located at the rear of the engine and ensures that the delivery pressure remains at 4.0 bar (58 lbf.in)
by controlling the amount of fuel returning to the fuel tank.
The fuel pump has a maximum current draw of 15 Amps at 12 Volts and is supplied a feed (C0114-1) from the fuel
pump relay (C0730-2) on a white/purple wire.
Fuel Gauge Sender
The fuel gauge sender unit comprises a rotary potentiometer operated by a float. The float rises and falls with the
fuel level in the tank and moves the potentiometer accordingly.
A feed is supplied to the fuel gauge sender (C0114-1) by the fuel pump relay (C0730-2) on a purple/white then
white/purple wire. The sender is earthed (C0114-3) on a slate/black wire via header 287. The output voltage
(C0114-2) from the sender to the instrument pack (C1061-3) varies in relation to the fuel level. This output voltage
is connected to the fuel gauge C1054-2). The fuel gauge receives a battery voltage input (C1054-3) on a
white/green wire. This is compared with the output voltage from the potentiometer. The difference between the two
voltages determines the deflection of the fuel gauge pointer.
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37MANUAL GEARBOX
4
REPAIR MECHANISM AND HOUSING - GEAR SELECTOR
Service repair no - 37.16.37
Remove
1.Remove gear lever knobs.
2.Remove gearbox tunnel carpet.
3.Remove gear lever gaiter(s)
4.Release and remove insulation pad from around
gear levers.
5.Remove 2 screws securing relay/fuse panel and
collect 2 spacers.
6.Release bulkhead carpet from LH side of tunnel
and move aside.
7.Remove 13 screws securing tunnel cover.
8.Release and remove tunnel cover.
9.Remove 4 bolts securing gear change housing,
remove housing, remove and discard gasket.
10.Using a suitable piece of tubing located over
ends of bias spring, release both ends of bias
spring from ball pins.
11.Loosen locknuts and remove bias spring
adjusting screws.
12.Drift out roll pin, remove bias spring.
13.Remove nut and extension from lower gear
lever.
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MANUAL GEARBOX
5
REPAIR
14.Remove bolt and special washer securing lower
gear lever in housing.
15.Carefully withdraw lower gear lever from the
housing ensuring that the spring loaded nylon
pad is retained during removal.
WARNING: Personal injury may result if
nylon pad is not retained.
16.Release nylon pad, recover spring.
Refit
17.Clean components, gear change housing and
mating face on remote housing.
18.Apply multi - purpose grease to ball pin and fit
spring and nylon pad.
19.Depress nylon pad against spring pressure,
position lower gear lever in housing with the
nylon pad facing away from bias spring location.
20.Fit lower gear lever retaining bolt and special
washer and tighten bolt to10 Nm (7 lbf.ft).
21.Fit upper gear lever to lower gear lever and
tighten nut to25 Nm (18 lbf.ft).
22.Drift new roll pin into housing.
23.Fit bias spring adjusting screws and locknuts.
24.Using a suitable piece of tubing, locate both
ends of bias spring over ball pins.
25.Fit new gasket to remote housing, position gear
change housing to remote housing and tighten
bolts to25 Nm (18 lbf.ft).26.Adjust bias springs.See Adjustment.
27.Fit and align tunnel cover, fit and tighten screws.
28.Secure bulkhead carpet to LH side of tunnel.
29.Position relay/fuse panel, fit spacers and tighten
screws.
30.Fit insulation pad around gear levers.
31.Fit gear lever gaiter(s).
32.Fit gearbox tunnel carpet.
33.Fit gear lever knobs.
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37MANUAL GEARBOX
6
REPAIR MECHANISM AND HOUSING - GEAR SELECTOR -
RESEAL
Service repair no - 37.16.37.01
Remove
1.Remove gear lever knobs.
2.Remove gearbox tunnel carpet.
3.Remove gear lever gaiter(s).
4.Release and remove insulation pad from around
gear levers.
5.Remove 2 screws securing relay/fuse panel and
collect 2 spacers.
6.Release bulkhead carpet from LH side of tunnel
and move aside.
7.Remove 13 screws securing tunnel cover.
8.Release and remove tunnel cover.
9.Remove 4 bolts securing gear change housing,
remove housing, remove and discard gasket.
Refit
10.Clean gear change housing and mating face on
remote housing.
11.Fit new gasket to remote housing, position gear
change housing to remote housing; fit bolts and
tighten to25 Nm (18 lbf.ft).
12.Fit and align tunnel cover, fit and tighten screws.
13.Secure bulkhead carpet to LH side of tunnel.
14.Position relay/fuse panel, fit spacers and tighten
screws.
15.Fit insulation pad around gear levers.
16.Fit gear lever gaiter(s).
17.Fit gearbox tunnel carpet.
18.Fit gear lever knobs.
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MANUAL GEARBOX
7
REPAIR GEARBOX
Service repair no - 37.20.02.99
Remove
1.Disconnect battery negative lead.
2.Remove gear lever and transfer gearbox lever
knobs.
3.Remove gearbox tunnel carpet.
4.Remove gear lever cover.
5.Remove nut and washer securing gear lever to
lower splined lever.
6.Mark gear lever spline setting to lower lever and
remove lever.
7.Release and remove insulation pad from tunnel.
8.Remove trim stud and lift up handbrake gaiter for
access to clevis pin.
9.Remove split pin, clevis pin, washer and
disconnect cable from handbrake lever; discard
split pin.
10.Remove 2 bolts securing hand-brake lever to
body, disconnect Lucar and remove lever.
11.Remove 2 screws securing relay panel and
collect 2 spacers.
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MANUAL GEARBOX
11
REPAIR Refit
44.Clean gearbox to engine mating faces, dowels
and dowel holes.
45.With assistance raise gearbox on jack and align
to clutch and engine.
46.Fit lower bolts securing clutch housing to engine
and tighten to50 Nm (37 lbf.ft).
NOTE: Do not fit upper bolts at this stage.
47.Fit earth leads and secure with bolt.
48.Connect Lucars to differential lock switch,
multiplug to reverse light switch, position
multiplug to bracket and connect low ratio detect
multiplug - if fitted.
49.Raise gearbox jack and guide transfer gearbox
lever through tunnel.
50.Secure body harness clips to bracket on top of
transfer gearbox.
51.Position battery earth lead to transfer gearbox
and tighten retaining nut.
52.Connect multiplug to speed sensor and secure
harness in clip on transfer gearbox.
53.Position mounting brackets and rubber
mountings, positioning heat shield to LH
mounting and tighten bracket bolts to85 Nm (63
lbf.ft).
54.Position nuts to mountings and tighten to48 Nm
(35 lbf.ft).
55.Remove 3 bolts securing support plate
LRT-99-007to gearbox.
56.Position handbrake cable through heel board.
57.Position clutch slave cylinder, fit bolts and
tighten to25 Nm (18 lbf.ft).
58.Clean propeller shafts and mating faces.
59.Position propeller shafts, align to marks and
tighten nuts to48 Nm (35 lbf.ft).
60.Clean intermediate silencer and tail pipe mating
faces.
61.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts and
tighten to25 Nm (18 lbf.ft).
62.Refill gearbox with oil.See Adjustment.
63.Refill transfer gearbox with oil.See
MAINTENANCE ,
64.Fit exhaust front pipe.See MANIFOLD AND
EXHAUST SYSTEM, Repair.
65.Refit starter motor.See ELECTRICAL, Repair.
66.Fit bolt securing shim plate to clutch housing and
tighten10 Nm (7 lbf.ft).
67.Position heater pipe to gearbox housing, fit
upper bolts securing clutch housing to engine
and tighten to50 Nm (37 lbf.ft).
68.Position gearbox breather pipes to clips on
heater hose.69.Fit air cleaner.See FUEL SYSTEM, Repair.
70.Fit cooling fan.See COOLING SYSTEM,
Repair.
71.Fit and align tunnel cover, fit and tighten screws.
72.Position relay panel, fit spacers and tighten
screws.
73.Position hand-brake lever and tighten bolts to25
Nm (18 lbf.ft).
74.Connect handbrake cable to lever, fit clevis pin,
washer and new split pin.
75.Connect Lucar to hand-brake switch.
76.Position gaiter to handbrake lever and secure
with trim stud.
77.Locate insulation pad over gear levers and fit to
tunnel cover.
78.Align spline marks, fit gear lever to lower lever,
fit washer and secure with retaining nut.
79.Position gear lever cover.
80.Position gearbox tunnel carpet.
81.Fit gear lever and transfer gear lever knobs.
82.Reconnect battery negative lead.
83.Fit battery cover.
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