fuel LAND ROVER DISCOVERY 1999 Workshop Manual
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 1999, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 1999Pages: 1529, PDF Size: 34.8 MB
Page 406 of 1529
FUEL DELIVERY SYSTEM - V8
DESCRIPTION AND OPERATION 19-2-9
Injectors
1'O' ring 2 off
2Electrical connector
3Steel housing
4Filter strainer
5Spring6Valve needle and armature
7Valve seat/spray orifice
8Plastic housing
9Solenoid winding
An injector for each cylinder is mounted externally in the lower inlet manifold on the engine. The injector protrudes
into the inlet manifold tract, where it releases a controlled delivery of fuel into the manifold air inlet.
Each injector is sealed to the fuel rail and the inlet manifold with 'O' rings. Spring clips retain each injector to the fuel
rail and the attachment of the fuel rail clamps the injectors in the lower manifold.
The injector housing is manufactured from plastic which encapsulates a high-alloy steel housing. The steel housing
contains all components which come into contact with fuel. The plastic housing also provides the attachment for the
engine harness connector for the injector. A solenoid is located between the two housings and moves a valve needle
via an armature. The valve needle seats on a valve seat which incorporates a spray orifice plate. A filter strainer is
fitted at the connection with the fuel rail to remove any particulate matter from the fuel before it enters the injector.
When the ECM energises the solenoid, the armature moves lifting the valve needle off its seat. This allows
pressurised fuel from the fuel rail to pass through the injector housing and needle to the spray orifice. The spray orifice
controls the spray shape and fuel metering. When the solenoid is de-energised, the valve needle returns to the valve
seat, aided by a spring, closing off the injection of fuel into the inlet.
Each injector receives a battery supply voltage via a fuse in the engine compartment fusebox. The fuel delivery timing
is controlled by the ECM, which, at a precisely timed interval, provides a ground path for the injector. The completion
of the ground path operates the injector to allow fuel at pump pressure to be delivered from the fuel rail to the injector
nozzle. Each injector sprays a finely atomized spray of fuel into the inlet, where it is mixed with the intake air prior to
combustion.
+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine
management.
Faults for each injector are stored in the ECM and can be retrieved using TestBook. Each injector can be checked
across the two connector pins. For a correctly functioning injector a resistance of between 13.8 and 15.2 ohms at a
temperature of 20°C (65°F) should be read across the pins.
Page 407 of 1529
FUEL DELIVERY SYSTEM - V8
19-2-10 DESCRIPTION AND OPERATION
Operation
When the ignition switch is moved to position II, the fuel pump relay in the engine compartment fusebox is energised
by the ECM. Battery voltage is supplied from the fuel pump relay to the fuel pump which operates. If engine cranking
is not detected by the ECU within a thirty second period, the ECU will 'time-out', de-energising the fuel pump relay.
+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine
management.
The fuel pump draws fuel from the swirl pot and pumps it along the fuel feed pipe to the injector fuel rail on the engine.
When the pressure in the fuel feed line reaches 3.5 bar (50 lbf.in
2) the fuel pressure regulator opens and relieves
pressure by directing fuel back into the swirl pot. The pressure regulator is constantly opening and closing to maintain
the pressure in the fuel feed pipe and the fuel rail at 3.5 bar (50 lbf.in
2).
The pressure is felt at each of the eight injectors connected to the fuel rail. The ECM controls the injection timing and
energises each injector to allow a metered amount of fuel at pump pressure to be injected into the inlet tract of the
inlet manifold. The atomised fuel from the injector is mixed with air from the inlet manifold before passing into the
cylinder.
Page 408 of 1529
FUEL DELIVERY SYSTEM - V8
ADJUSTMENTS 19-2-11
ADJUST ME NTS
Fuel tank - drain
$% 19.55.02
Drain
1.Disconnect both leads from battery.
WARNING: Always disconnect the negative
lead first. Disconnection of the positive lead
while the negative lead is connected could
result in a short circuit through accidental
grounding and cause personal injury.
2.Connect TestBook to vehicle and depressurise
fuel system.
3.Remove fuel pump.
+ FUEL DELIVERY SYSTEM - V8,
REPAIRS, Pump - fuel.
4.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.
Refill
1.Fit fuel pump unit.
+ FUEL DELIVERY SYSTEM - V8,
REPAIRS, Pump - fuel.
2.Refill fuel tank with extracted fuel.
3.Connect battery leads, positive lead first.
Page 410 of 1529
FUEL DELIVERY SYSTEM - V8
REPAIRS 19-2-13
REPAIRS
Switch - inertia - fuel cut-off
$% 19.22.09
Remove
1.Disconnect multiplug from fuel cut-off switch.
2.Remove 2 screws securing fuel cut-off switch to
bulkhead.
3.Remove fuel cut-off switch from bulkhead.
Refit
1.Position fuel cut-off switch to bulkhead and
secure with screws.
2.Connect multiplug to fuel cut-off switch.
3.To set the fuel cut-off switch, depress the top of
the fuel cut-off switch.
Pump - fuel
$% 19.45.08
NOTE: The fuel pump and fuel gauge tank unit are
integral parts of the fuel pump housing and cannot be
renewed separately
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery earth lead.
3. Models with third row seats: Remove RH
third row seat.
+ SEATS, REPAIRS, Seat - third row.
4. Remove right hand rear lower quarter trim
casing.
+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
5. Models with third row seats: Remove 4
screws securing third row seat latch finishers to
body and finishers.
6.Release and remove screw cover from rear
floor carpet finisher.
7.Remove 6 screws securing loadspace carpet
finisher, remove finisher.
8.Release carpet and tie aside.
Page 411 of 1529
FUEL DELIVERY SYSTEM - V8
19-2-14 REPAIRS
9.Remove 6 screws securing fuel pump access
panel to floor.
10.Remove access panel.
11.Clean fuel pump hose connections.
12.Position absorbent cloth to absorb fuel spillage.
13.Disconnect multiplug and fuel hose from fuel
pump housing.
CAUTION: Always fit plugs to open
connections to prevent contamination.
14. NAS models: Disconnect pressure sensor
pipe from fuel pump housing.
CAUTION: Always fit plugs to open
connections to prevent contamination.
15.Use LRT-19-009 to remove locking ring from
fuel pump housing.
16.Remove fuel pump and discard sealing ring. Refit
1.Clean fuel pump housing and mating face on
fuel tank.
2.Fit new seal to mating face on fuel tank.
3.Fit fuel pump assembly to fuel tank and use
LRT-19-009 to fit locking ring.
4.Connect multiplug and fuel hose to fuel pump
housing.
5. NAS models: Connect pressure sensor pipe to
fuel pump housing.
6.Fit fuel pump access panel and secure with
screws.
7.Reposition carpet.
8.Fit carpet finisher and secure with screws.
9.Fit screw cover.
10. Models with third row seats: Fit and secure
third row seat latch finishers.
11.Fit right hand rear lower quarter trim casing.
+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
12. Models with third row seats: Fit RH third row
seat.
+ SEATS, REPAIRS, Seat - third row.
13.Connect battery earth lead.
14.Fit battery cover and secure with fixings.
Page 412 of 1529
FUEL DELIVERY SYSTEM - V8
REPAIRS 19-2-15
Tank - fuel
$% 19.55.01
Remove
1.Drain fuel tank.
+ FUEL DELIVERY SYSTEM - V8,
ADJUSTMENTS, Fuel tank - drain.
2.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
3. All except NAS models:Release clips
securing filler and breather hoses. Release
hoses from filler tube.
4. NAS models: Loosen securing clip and
release filler tube from fuel tank.
5.Disconnect fuel tank vent pipe from filler tube.
6.Support weight of fuel tank underneath cradle. 7.Remove 2 nuts and 2 bolts securing cradle to
chassis.
8.With assistance, lower LH side of fuel tank then
remove fuel tank from chassis.
9.Remove cradle from fuel tank.
Non NAS fuel tank
10.Remove 2 scrivets securing heat shield and
remove heat shield.
11. All except NAS models: Release securing clip
and remove breather hose from fuel tank.
Refit
1.Fit breather hose to fuel tank and secure with
clip.
2.Position heat shield and secure with scrivets.
3.With assistance, position fuel tank and cradle.
4.Fit nuts and bolts securing cradle to chassis.
Tighten bolts to 45 Nm (33 lbf.ft) and nuts to 26
Nm (19 lbf.ft).
5.Connect vent hose.
6.Connect breather and filler hoses and secure
with clips.
Page 413 of 1529
FUEL DELIVERY SYSTEM - V8
19-2-16 REPAIRS
Filler tube - fuel
$% 19.55.07
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Ensure fuel tank is less than half full. If not,
drain fuel tank to less than half full.
+ FUEL DELIVERY SYSTEM - V8,
ADJUSTMENTS, Fuel tank - drain.
3.Remove filler cap.
Non NAS installation
4.Drill out rivet securing lower part of mud flap
support bracket and release bracket .
5. All except NAS models: Position suitable
container beneath filler tube and disconnect
filler hose, breather hose and vent pipe from
filler tube.
WARNING: TAKE ALL NECESSARY
PRECAUTIONS AGAINST FIRE AND
EXPLOSION.
NAS installation6. NAS models: Position suitable container
beneath filler tube to tank connection , loosen
securing clip and release filler tube from fuel
tank.
WARNING: TAKE ALL NECESSARY
PRECAUTIONS AGAINST FIRE AND
EXPLOSION.
7. NAS models: Disconnect vent pipes from filler
tube.
8. Release filler tube from grommet in body and
remove from under rear wing. Collect grommet.
9. NAS models: Remove cable tie securing
pressure sensor pipe to filler tube and remove
filler tube.
Refit
1. NAS models: Position filler tube to pressure
sensor pipe and secure with new cable tie.
2. Fit grommet to body, position filler tube under
rear wing and secure in grommet.
3. NAS models: Connect filler tube to fuel tank
and secure with clip. Connect vent pipes to filler
tube.
4. All except NAS models: Connect filler hose
and breather hose to filler tube and secure with
clips. Connect vent pipe to filler tube.
5. Position support bracket to mud flap and
secure with new rivet.
6.If applicable, refill fuel tank with extracted fuel.
7.Fit filler cap.
8.Remove stand(s) and lower vehicle.
Page 414 of 1529
FUEL DELIVERY SYSTEM - V8
REPAIRS 19-2-17
Solenoid - fuel filler flap release
$% 19.55.17
Remove
1.Remove loadspace RH side trim casing.
+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
2.Remove 2 nuts and release solenoid from
body panel.
3.Disconnect multiplug and remove solenoid.
Refit
1.Position solenoid and connect multiplug.
2.Position solenoid to panel and tighten nuts.
3.Fit loadspace RH side trim casing.
+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
Switch - fuel filler flap release - up to
03MY
$% 19.55.23
Remove
1.Carefully remove switch.
2.Disconnect multiplug from switch.
3.Remove switch.
Refit
1.Connect multiplug switch.
2.Position switch and push to secure.
Page 415 of 1529
FUEL DELIVERY SYSTEM - V8
19-2-18 REPAIRS
Switch - fuel filler flap release - from
03MY
$% 19.55.23
Remove
1.Remove 2 screws securing instrument cowl to
fascia and release the cowl from the retaining
clips.
2.Disconnect multiplug from the fuel filler flap
release switch.
3.Remove the fuel filler flap release switch from
the instrument cowl.
Refit
1.Fit and secure the fuel filler flap release switch
to the instrument cowl and connect the
multiplug.
2.Fit the instrument cowl to the fascia and secure
with screws.
Page 424 of 1529
COOLING SYSTEM - V8
DESCRIPTION AND OPERATION 26-2-9
Viscous fan
1Coolant pump pulley drive attachment
2Fan blades3Bi-metallic coil
4Body
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 the coolant pump drive pulley and secured to the pulley by a nut. The nut is positively
attached to a 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 coolant pump pulley and the coupling body. The drive plate and the
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'.
At low radiator temperatures, the fan operation is not required and the bi-metallic coil keeps the valve closed,
separating the silicone fluid from the drive plate. This allows the fan to 'freewheel' reducing the load on the engine,
improving fuel consumption and reducing noise generated by the rotation of the fan.
When the radiator temperature increases, the bi-metallic coil reacts and moves the valve, allowing the silicone fluid
to flow into the fluid chamber. The resistance to shear of the silicone fluid creates drag on the drive plate and provides
drive to the body and the fan blades.