1999 LAND ROVER DEFENDER oil filter

12ENGINE
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DESCRIPTION AND OPERATION Oil cooler
1.Front oil gallery - full-flow filter to oil cooler matrix
2.Full-flow filter adaptor outlet port to oil cooler
(opens at 74°C)
3.Full-flow filter inlet port
4.Oil cooler housing
5.Full-flow filter outlet port to cylinder block
6.Coolant inlet port
7.Oil cooler banjo bolt seals (2 off)
8.Banjo bolts (2 off)
9.Banjo bolt oil holes - to oil cooler matrix
10.Rear oil gallery - full-flow filter / oil cooler outlet
to cylinder block11.Centre oil gallery - from pump to full-flow filter
12.Inlet port to centrifuge filter
13.Sealing ring - centrifuge filter housing to oil
cooler housing
14.Port - oil cooler matrix
15.Oil cooler matrix
16.Inlet port from pump via cylinder block to oil
cooler housing
17.Outlet port from oil cooler housing to cylinder
block
18.Rear view of oil cooler housing
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ENGINE
17
DESCRIPTION AND OPERATION The engine oil cooler assembly is located on the left hand side of the engine block behind the oil centrifuge and oil
filter. The housing is bolted to the engine block by seven bolts. A matrix is included in the oil cooler housing which
acts as a heat exchanger. Coolant flow circulates through the oil cooler housing under pressure from the coolant
pump and distributes the flow evenly around the matrix fins and then along the block into three core holes for
cylinder cooling. Coolant enters the oil cooler through a pipe with a rubber hose extension at the rear side of the
engine. The coolant hose is attached to the stub pipe of the oil cooler by a spring clip.
Oil, drawn from the sump by the oil pump, passes through the oil cooler via the cylinder block. The flow of coolant
around the exterior surface of the oil cooler matrix cools a proportion of the engine oil flow as it passes through the
oil cooler.
The oil cooler is sealed to the cylinder block by a gasket which must be replaced every time the oil cooler housing
is removed.
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12ENGINE
18
DESCRIPTION AND OPERATION Oil filters
The Td5 engine features two types of oil filter; the main filter is a standard disposable cartridge-type full flow oil
filter which is augmented with a by-pass centrifuge filter used to filter out particulate matter having a smaller
diameter smaller than 15 micron but greater than 3 micron.
1.Centre spindle
2.Spindle oil holes (2 off)
3.Centrifuge filter housing
4.Centrifuge filter drain pipe
5.Port - centrifuge filter drain pipe to sump6.Filter rotor
7.Internal seal
8.Cover
9.Cover screws (2 off)
The centrifuge filter is located on the left hand side of the engine block by the exhaust manifold and is housed in a
pot which is bolted to the oil cooler housing by means of three bolts. The pot contains a rotor located on a central
spindle which spins at up to 15,000 rev/min when oil is flowing through the unit under pressure. The rotor contains
two fine holes drilled at obtuse angles which cause the rotor to spin about the centre spindle when high pressure
oil is passing through it. The inner surface of the rotor captures carbon deposits and small particulate matter as it
is thrown outwards under centrifugal force to form a sludge on the inner walls of the rotor. The unit is able to trap
very fine impurities that build up in the oil that would be too small to filter using the normal paper-element type
full-flow filters alone.
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ENGINE
19
DESCRIPTION AND OPERATION Full flow filter
Approximately 10% of the total oil flow enters the centrifuge pot through a side port in the pot casting which is
mated to an outlet port at the lower side of the oil cooler housing. A rubber’O’ring sits in a recess around the oil
cooler port which seals the faces between the centrifuge pot and oil cooler port, and it must be replaced every
time the centrifuge assembly is removed. Oil leaves the centrifuge pot through a drain tube which is attached to
the base of the pot by means of two fixing screws. The lower end of the drain tube returns oil to the sump and is
fixed to the sump by means of two screws. Gaskets are included at the port interfaces between the oil drain tube
and the centrifuge pot and the oil drain tube and sump return port; these gaskets must be replaced every time the
oil drain tube is removed.
The centrifuge cover is fixed to the pot by two screws and is sealed by an’O’ring.
1.Full-flow filter housing
2.Thermostat
3.Roll-pin4.Port - feed line to turbocharger
5.Outlet port from full-flow filter - higher than 74°C
6.Inlet port to full-flow filter
7.Outlet port from full-flow filter - lower than 74°C
The main filter is a conventional full flow cartridge type filter containing a paper element able to trap particles
greater than 15 micron (0.015 mm) in diameter.
The cartridge is screwed to an adaptor casting by way of a hollow brass threaded insert which connects the filter
outlet port to the adaptor casting. A sealing ring seals the union between the oil filter cartridge and the adaptor
casting.
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12ENGINE
20
DESCRIPTION AND OPERATION Oil filter housing thermostat
1.Circlip
2.Thermostat end cap
3.Oil seal
4.Thermostatic valve5.Return spring
6.Oil filter housing
7.Threaded insert
The oil filter housing contains a thermostatically controlled valve to control the direction and proportion of oil flow
through the oil cooler matrix. When the oil temperature is cool, the centre spindle of the thermostatic element is
compressed. In this condition the valve completely seals the passage to the turbocharger feed tapping and flow is
directed through the oil filter adaptor housing, passing from the outlet of the full-flow filter to the cylinder block via
the rear oil return gallery in the oil cooler housing. A proportion of the oil flow from the right hand filter outlet port is
passed through to the oil cooler matrix to supply the turbocharger oil feed line.
When the oil temperature rises, the heated wax in the thermostat causes the thermostat centre spindle to rise and
push against the housing end cap, compressing the valve spring further and so opening the valve. In this
condition, oil flow from the outlet side of the full-flow filter is allowed to pass directly to the turbocharger oil feed
line and reverses the flow through the oil cooler matrix, which now delivers a proportion of cooled oil flow to the
cylinder block via the outlet port at the right hand side of the oil cooler housing.
The filter canister contains a by-pass valve which opens when the engine is cold or if the filter becomes blocked.
The by-pass valve opens when a pressure drop of greater than 1.6 kg/cm
2(157 kPa, 23 lbf/in2) is experienced.
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12ENGINE
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DESCRIPTION AND OPERATION CRANKSHAFT, SUMP AND OIL PUMP
The crankshaft, sump and oil pump components are described below:
Sump
The sump is a wet-type, of aluminium construction and is sealed to the engine block by means of a rubber gasket
and twenty fixing bolts. The four bolts at the gearbox end of the sump are longer than the other sixteen bolts.
The sump gasket incorporates compression limiters (integrated metal sleeves) at the bolt holes, which are
included to prevent distortion of the gasket when the sump to cylinder block bolts are being tightened.
An oil drain plug is fitted at the bottom of the oil sump reservoir. An oil return drain pipe is also attached to the oil
sump which returns oil from the centrifugal filter.
Stiffener Plate
The stiffener plate assembly provides lower engine block rigidity and utilises dowels to align it to the bottom of the
cylinder block. A rotary oil pump is integral with the stiffener plate and an oil pick-up and strainer assembly is fitted
to the underside of the stiffener plate. The stiffener and oil pump assembly is secured to the cylinder block by 22
bolts.
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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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12ENGINE
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DESCRIPTION AND OPERATION OIL COOLER / FILTER FLOW
(THERMOSTAT OPEN)
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