1999 LAND ROVER DEFENDER oil level

ENGINE
33
DESCRIPTION AND OPERATION 1.Oil squirt jets (5 off)
2.Main oil delivery gallery
3.Inflow from oil cooler housing
4.Flow to oil cooler / filters (from oil pump via cylinder block)
5.Sump
6.Oil pick-up pipe
7.Flow from oil pump (relief-valve in housing)
8.Oil pump
9.Cross-drilling supply to main and crankshaft bearings
10.To cylinder head
Oil from the sump is drawn up through a two-piece plastic pick-up which contains a mesh to siphon any relatively
large pieces of material which could cause damage to the pump. The head of the pick-up is centrally immersed in
the sump oil and oil is delivered to the inlet side of the eccentric rotor pump through a gallery in the stiffener plate.
Pressurised oil from the pump is passed through to the cylinder block where it is delivered to the centrifuge filter
and full-flow filter via a port in the RH cylinder block which interfaces with a port in the centre gallery of the oil
cooler housing. The oil pump contains an oil pressure relief valve which opens to allow oil to be recirculated back
around the pump if the oil pressure increases to a high enough level.
10% of the oil flow from the pump is diverted through the centrifuge filter and returned to the sump via the
centrifuge filter drain tube. The remaining 90% of the oil passes through the standard full-flow filter to the main oil
gallery in the cylinder block.
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ENGINE
35
DESCRIPTION AND OPERATION 1.To cylinder block main gallery (from rear of oil cooler housing)
2.Oil cooler housing
3.Oil pressure switch
4.Full-flow filter
5.Centrifuge filter
6.Return to sump
7.Flow from oil pump (via cylinder block)
8.Oil cooler matrix
When the engine temperature is below 74°C, the thermostat in the full-flow filter adaptor housing is closed and a
proportion of the oil flow to the main oil gallery is diverted to the oil cooler to supply an oil feed to the turbocharger
bearings. Oil passes through the oil cooler to the front gallery in the oil cooler housing where there is a tapping to
connect the feed pipe to the turbocharger. Oil used by the turbocharger bearings is returned to the sump through
an oil drain pipe which connects to a port in the LH side of the cylinder block.
The remainder of the oil flow leaving the full-flow filter outlet is passed into the cylinder block via a port at the rear
of oil cooler rear gallery.
When the oil temperature rises above 74°C the thermostat in the full-flow filter housing begins to open to allow a
proportion of the oil from the full-flow filter to pass through the oil cooler before it reaches the main oil gallery in the
cylinder block. In this instance, oil supply to the turbocharger bearings is fed directly from the full-flow filter without
first passing through the oil cooler. Between 74°C and 88°C the thermostat valve plunger opens by about 9 mm
(0.3 in) to allow proportionally more oil to flow through the oil cooler before being passed to the cylinder block main
oil delivery gallery. Above 88°C the thermostat valve continues to open by about 1mm (0.03 in) for every 10°C
increase in temperature until the valve is fully open, when all the oil flow to the cylinder block is forced to pass to
the cylinder block via the oil cooler.
An oil pressure switch is located in a port in the rear gallery of the oil cooler housing to sense the oil pressure level
before flow enters the main oil gallery in the engine block. A warning lamp in the instrument cluster is switched on
if the oil pressure is detected as being too low.
Drillings from the cylinder block main oil gallery direct oil to the crankshaft main bearings and cross drillings in the
crankshaft direct oil to the big-end bearings. An additional five drillings in the cylinder block supply oil at reduced
pressure to the oil squirt jets for piston cooling and gudgeon pin lubrication.
Oil supply from the cylinder block is then passed to the cylinder head galleries through a non-return valve which is
included as an integral item in the lower face of the cylinder head.
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ENGINE
23
REPAIR FILTER - OIL
Service repair no - 12.60.04
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
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 manifold heat
shield.
7.Clean area around filter head and place a
container beneath engine.
8.Using a strap wrench, unscrew and discard filter.
Refit
9.Clean mating face of filter head.
10.Lubricate sealing ring of new filter with clean
engine oil.
11.Fit filter and tighten by hand until it seats then
tighten a further half turn.
12.Start and run engine to check for leaks.
13.Stop engine, wait a few minutes, then check oil
level.
14.Top up engine oil.
15.Position exhaust manifold heat shield and
tighten 3 bolts.
16.Position air inlet hose to turbocharger and
tighten clip screw.
17.Connect air flow meter to air filter and secure
clips.
18.Connect air flow meter multiplug.
19.Connect breather hose and secure with clip.
20.Position engine acoustic cover.
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ENGINE
29
REPAIR VALVE - RELIEF - OIL PRESSURE
Service repair no - 12.60.56
Remove
1.Remove sump gasket.See this Section.
2.Remove and discard oil pressure relief valve
plug from oil pump housing.
3.Remove spring and valve.
Refit
4.Clean valve and spring.
5.Clean valve seating inside oil pump housing.
6.Lubricate valve and seating.
7.Fit valve and spring to pump.
8.Apply Loctite 243 sealant to threads of a new
plug.
9.Fit plug and tighten to23 Nm ( 17 lbf.ft).
10.Fit sump gasket.See this Section.
11.Check engine oil level, top-up if necessary.COOLER - ENGINE OIL
Service repair no - 12.60.68
Remove
1.Drain cooling system.See COOLING
SYSTEM, Adjustment.
2.Remove centrifuge assembly.See this
Section.
3.Remove clutch housing bolt and release coolant
pipe from rear of engine.
4.Release clip and coolant hose from oil cooler.
5.Disconnect oil pressure switch multiplug.
6.Remove oil filter element using a suitable strap
wrench.
7.Remove 3 bolts, remove oil filter adaptor and
discard gasket.
8.Remove 7 bolts, remove oil cooler and discard
gasket.
9.Remove oil pressure switch.
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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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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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26COOLING SYSTEM
12
DESCRIPTION AND OPERATION Viscous Fan Operation
A = Cold
B = Hot
1.Drive plate
2.Fan body
3.Clearance
4.Valve plate
5.Valve
6.Bi-metallic coil7.Fluid seals
8.Ball race
9.Fluid chamber
10.Reservoir
11.Return port
When the engine is off and the fan is not rotating, the silicone fluid stabilises within the fluid chamber and the
reservoir. The fluid levels equalise due to the return port in the valve plate being open between the fluid chamber
and the reservoir. In this condition, when the engine is started, silicone fluid is present in the fluid chamber and
causes drag to occur between the drive plate and the body. This causes the fan to operate initially when the
engine is started.
As the fan speed increases, centrifugal force and a scoop formed on the fluid chamber side of the valve plate,
pushes the silicone fluid through the return port in the valve plate into the reservoir. As the fluid chamber empties,
the drag between the drive plate and the body is reduced, causing the drive plate to slip. This reduces the
rotational speed of the fan and allows it to’freewheel’.
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37MANUAL GEARBOX
2
ADJUSTMENT GEARBOX OIL - DRAIN AND REFILL
Service repair no - 37.24.01
Drain
1.The oil should be drained when the gearbox is
warm and the vehicle is standing on a level
surface.
WARNING: Observe due care when
draining gearbox as oil can be very hot.
2.Raise vehicle on ramp.
3.Position container to collect oil.
4.Clean area around filler/level plug.
5.Remove filler/level plug.
NOTE: Later gearboxes: Use No. 55 Torx
bit to remove filler/level plug.
6.Remove gearbox drain plug and discard sealing
washer.Refill
1.Clean gearbox drain plug and fit new sealing
washer.
2.Fit gearbox drain plug and tighten to50 Nm (36
lbf.ft).
3.Fill gearbox with correct grade of oil.See
LUBRICANTS, FLUIDS AND CAPACITIES,
Information.
4.Apply Loctite 290 to the filler/level plug and
tighten to30 Nm (22 lbf.ft).
5.Remove fluid container.
6.Lower vehicle on ramp.
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