1999 LAND ROVER DEFENDER battery

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.
ProCarManuals.com

FUEL SYSTEM
1
ADJUSTMENT HEATER PLUG TEST
Service repair no - 19.90.20.01
Check
1. Test out of engine
2.Remove heater plug.See Repair.
3.UsingLRT-12-511,connect RED lead to battery
’+’positive and the BLACK lead to battery’-’
negative.
4.Position heater plug into tester and retain with
spring loaded bar.
5.Connect YELLOW lead to heater plug terminal.
6.Press red button on tester and note ammeter
reading. Keep button depressed, heater plug tip
should start to glow after 5 seconds
CAUTION: The heater plug tip must glow
first, if it fails to do so, replace heater plug.
7.The ammeter reading should show an initial
current draw of 25 amps, which should fall to 12
amps after 20 seconds.
8.Refit heater plug.See Repair.FUEL SYSTEM - BLEED
Service repair no - 19.50.07
Fuel Purging Procedure
1.If the vehicle runs out of fuel, or the fuel level is
so low that the fuel system draws air into the fuel
rail, the fuel rail will need to be purged before the
engine will start. This can be achieved by
following a set procedure. The process does not
require the use of any specialist equipment and
can be performed by the driver of the vehicle.
The process is as follows:
2.Switch off ignition and wait 15 seconds.
3.Turn ignition key to position 2 and wait 3
minutes, (this ensures that the fuel system
purges all the air from the fuel rail within the
cylinder head).
4.Depress the throttle pedal to more than 90% of
its total travel, (to the throttle stop).
5.Crank the engine keeping the throttle pedal
depressed.
NOTE: This operation is controlled by the
ECM and it is important that the purging
operation is not carried out on a vehicle
that has not run out of fuel. If it is carried out
unnecessarily it can lead to the engine flooding
and failing to start.
This operation will be cancelled:
6.As soon as engine speed exceeds 600 rev/min.
7.The driver allows the throttle pedal to close to a
position less than 90% of its travel.
8.The ignition key is released from the start
position.
NOTE: The engine must not be cranked for
more than 30 seconds in any one period.
9.Repeat the above procedure if the engine fails to
start.
ProCarManuals.com

19FUEL SYSTEM
2
ADJUSTMENT FUEL TANK - DRAIN
Service repair no - 19.55.02
1.Remove battery cover.
2.Disconnect both leads from battery, earth lead
first.
WARNING: Fuel vapour is highly
flammable and in contained spaces is also
explosive and toxic. Always have a fire
extinguisher containing FOAM, CO2, GAS OR
POWDER close at hand when handling or draining
fuel.
3.Using a fuel recovery appliance, drain the fuel
from the tank into a sealed container. Follow the
manufacturers instructions for the connection
and safe use of the appliance.
4.Remove filler cap and insert hose into filler neck.
5.Connect bowser earth line. Drain fuel.
6.Connect battery leads.
7.Fit battery cover.
ProCarManuals.com

FUEL SYSTEM
1
REPAIR ELEMENT - AIR FILTER
Service repair no - 19.10.10
Remove
1.Release 2 clips and disconnect air flow meter
from air filter cover.
2.Disconnect multiplug from AAP sensor.
3.Release 2 clips and remove cover from air filter.
4.Remove air filter element.
Refit
5.Clean air filter body and cover.
6.Fit new air filter element.
7.Position air cleaner cover and secure clips.
8.Position air flow meter and secure clips.
9.Connect AAP sensor multiplug.SENSOR - FUEL TEMPERATURE
Service repair no - 19.22.08
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Release fixings and remove battery cover.
3.Disconnect battery negative lead.
4.Disconnect multiplug from fuel temperature
sensor.
5.Thoroughly clean area around fuel temperature
sensor before removal.
6.Remove fuel temperature sensor and discard
sealing washer.
Refit
7.Clean fuel temperature sensor mating faces.
8.Fit new sealing washer and tighten fuel
temperature sensor to13 Nm (9 lbf. ft).
9.Connect multiplug to fuel temperature sensor.
10.Reconnect battery negative lead.
11.Fit battery cover and secure fixings.
12.Fit engine acoustic cover and secure with bolts.
ProCarManuals.com

19FUEL SYSTEM
4
REPAIR ELEMENT - FUEL FILTER
Service repair no - 19.25.07
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery negative lead.
3.Raise rear of vehicle.
WARNING: Support on safety stands.
4.Release fixing and remove fuel filter cover.
5.Clean area around fuel filter.
6.Disconnect multiplug from filter element.
7.Remove fuel filter element.
Refit
8.Clean fuel filter and mating face.
9.Fit new fuel filter element and connect multiplug.
10.Position fuel filter cover and secure with fixing.
11.Remove stand(s) and lower vehicle.
12.Reconnect battery negative lead.
13.Fit and secure battery cover.COOLER - FUEL
Service repair no - 19.25.30
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Remove battery cover.
3.Disconnect battery negative lead.
4.Drain cooling system.See COOLING
SYSTEM, Adjustment.
5.Release 3 clips and disconnect 3 coolant hoses
from fuel cooler.
6.Release 2 fuel hoses from fuel cooler.
CAUTION: Plug the connections.
7.Release vacuum pipe clip from fuel cooler.
8.Remove 4 bolts securing fuel cooler to inlet
manifold and remove cooler.
Refit
9.Clean fuel hose connections.
10.Position fuel cooler to inlet manifold. Apply
Loctite 242 to bolts and tighten to18 Nm (13
lbf.ft).
11.Connect fuel hoses.
12.Connect coolant hoses, secure with clips.
13.Secure vacuum hose to fuel cooler.
14.Refill cooling system.See COOLING SYSTEM,
Adjustment.
15.Fit engine acoustic cover and secure with bolts.
16.Reconnect battery negative lead.
17.Fit battery cover.
ProCarManuals.com

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.
ProCarManuals.com

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.
ProCarManuals.com

FUEL SYSTEM
9
REPAIR HEATER PLUGS - SET
Service repair no - 19.60.31
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Remove battery cover.
3.Disconnect battery negative lead.
4.Disconnect 4 heater plug leads.
5.Loosen and remove 4 heater plugs.
Refit
6.Throughly clean heater plugs and seating area
in cylinder head.
7.Apply a suitable anti-seize compound to threads
of heater plugs.
8.Fit heater plugs and tighten to16 Nm (12 lbf. ft)
.
9.Connect heater plug leads.
10.Fit engine acoustic cover.
11.Reconnect battery negative lead.
12.Fit battery cover.INTERCOOLER
Service repair no - 19.42.15
Remove
1.Remove radiator.See COOLING SYSTEM,
Repair.
2.Release clip and remove air hose from
intercooler.
Refit
3.Position air hose to intercooler and secure with
clip.
4.Fit radiator.See COOLING SYSTEM, Repair.
ProCarManuals.com