2002 LAND ROVER DISCOVERY engine

ENGINE - TD5
12-1-30 DESCRIPTION AND OPERATION
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.

ENGINE - TD5
DESCRIPTION AND OPERATION 12-1-31
Oil cooler / Filter flow (thermostat open)
1To cylinder block main gallery (from rear of oil
cooler housing)
2Oil cooler housing
3Oil pressure switch
4Full-flow filter
5Centrifuge filter6Return to sump
7Flow from oil pump (via cylinder block)
8Oil cooler matrix

ENGINE - TD5
12-1-32 DESCRIPTION AND OPERATION
When the engine temperature is below 74° C, the thermostat in the full-flow filter 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 adaptor 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
9mm 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 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.

+ INSTRUMENTS, DESCRIPTION AND OPERATION, Description.
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.

ENGINE - TD5
DESCRIPTION AND OPERATION 12-1-33
Cylinder head flow
1Cast-in groove between cylinder head and
camshaft carrier
2Rocker shaft flow
3Lash adjuster supply channels (10 off)
4Non-return valve
5Chain lubrication jet supply6Oil return from vacuum pump
7Oil supply to timing chain tensioner adjuster
8Oil supply to vacuum pump
9Oil supply hole to camshaft sprocket and timing
chain
Oil passes to the cylinder head from the cylinder block via a non-return valve which is included to prevent oil draining
away from the lash adjusters when the engine is switched off.
Oil is passed to a cast-in groove between the top of the cylinder head and the camshaft carrier. The part of the channel
on the top left hand side of the cylinder head has ten cross-drillings which supply oil to the hydraulic lash adjusters
and finger followers. Lubrication oil fed to the lash adjusters passes up through the lash adjuster body and into the
socket of the finger followers. The oil exits the finger followers through a small hole to lubricate the surfaces between
the camshaft lobes and rollers.
An additional tapping is included at the front left hand side of the cylinder head to supply oil to the chain lubrication
jet, and a through hole near the front centre of the cylinder head allows a passage of oil through from the cast-in
groove to lubricate the timing chain and camshaft sprocket.
At the centre front of the cylinder head, the cast-in groove channels oil into the rockershaft via the front rockershaft
fixing. Oil flow through the rockershaft and clearance around the rockershaft fixings provides oil feed to the camshaft
bearings.

ENGINE - TD5
12-1-34 DESCRIPTION AND OPERATION
A tapping towards the right hand side of the cylinder head diverts oil supply from the cast-in groove down to a stub
pipe which attaches to a feed line to the vacuum pump. An hydraulic tensioner is located below the vacuum stub pipe
which receives oil through a small hole in the side of the tensioner body to force a plunger against a plastic faced
adjuster shoe for timing chain tensioning. Oil from the vacuum pump is returned to a port in the timing chain cover via
a short hose which connects to stub pipes at both ends using spring clips.

ENGINE - TD5
ADJUSTMENTS 12-1-35
ADJUST ME NTS
Engine oil pressure check
$% 12.90.09.01
Check
1.Remove oil pressure switch.

+ ENGINE - Td5, REPAIRS, Switch -
oil pressure.
2.Connect pressure check kit LRT-12-052C
adaptor and gauge to oil pressure switch
position on oil cooler.
3.Check and if necessary top up engine oil.
4.Run engine at idle speed and check that oil
pressure is within limits given.

+ GENERAL DATA, Engine - Td5.
5.Switch off ignition.
6.Remove pressure check kit LRT-12-052C.
7.Clean oil spillage.
8.Fit oil pressure switch.

+ ENGINE - Td5, REPAIRS, Switch -
oil pressure.
Adjust
1.If engine oil pressure is outside of specified
limits, check condition of oil pump and/or main
and connecting rod bearings.

ENGINE - TD5
12-1-36 ADJUSTMENTS

ENGINE - TD5
REPAIRS 12-1-37
REPAIRS
Pulley - crankshaft
$% 12.21.01
Remove
1.Remove fixings and underbelly panel.
2.Remove radiator.

+ COOLING SYSTEM - Td5, REPAIRS,
Radiator.
3.Using a 15 mm ring spanner, release the
auxiliary drive belt tensioner.
4.Remove auxiliary drive belt.
5.Remove 3 bolts and remove crankshaft TV
damper.
6.Position tool LRT-51-003 to crankshaft pulley
and secure with 2 bolts.
7.Remove and discard crankshaft pulley bolt.
Remove crankshaft pulley.
8.Remove 2 bolts and remove tool LRT-51-003
Refit
1.Position new crankshaft pulley to vice.
2.Remove 3 bolts and remove TV damper from
new crankshaft pulley.
3.Using a lint free cloth, thoroughly clean oil seal
recess and the running surface on crankshaft
pulley.
4.Fit crankshaft pulley. 5.Fit tool LRT-51-003 to crankshaft pulley and
secure with 2 bolts.
6.Fit new crankshaft pulley bolt and tighten to
460 Nm (340 lbf.ft), using a torque multiplier.
7.Remove 2 bolts and remove tool LRT-51-003
from crankshaft pulley.
8.Fit TV damper to crankshaft pulley and tighten
– TV damper bolts to 80 Nm (59 lbf.ft) .
9.Fit auxiliary drive belt to pulleys.
10.Fit radiator.

+ COOLING SYSTEM - Td5, REPAIRS,
Radiator.
11.Fit underbelly panel and secure with fixings.