cooling system - td5 LAND ROVER DISCOVERY 2002 User Guide

ENGINE - TD5
12-1-12 DESCRIPTION AND OPERATION
Description
General
The Td5 diesel engine is a 2.5 litre, 5 cylinder, in-line direct injection unit having 2 valves per cylinder, operated by a
single overhead camshaft. The engine emissions, on pre EU3 models, comply with ECD2 (European Commission
Directive) and on EU3 models, comply with ECD3 legislative requirements. Both models employ electronic engine
management control, positive crankcase ventilation and exhaust gas recirculation to limit the emission of pollutants.
The unit is water cooled and turbo-charged and is controlled by an electronic engine management system.
The engine is a monobloc cast iron construction with an aluminium stiffening plate fitted to the bottom of the cylinder
block to improve lower structure rigidity. The cylinder head and sump are cast aluminium. An acoustic cover is fitted
over the upper engine to reduce engine generated noise.
The engine utilises the following features:
lElectronic Unit Injectors (EUI's) controlled by an Engine Management System for precise fuel delivery under
all prevailing operating conditions.
lTurbocharging which delivers compressed air to the combustion chambers via an intercooler for improved
power output.
lFuel Cooler
lOil Cooler
lCentrifuge Oil Filter
lHydraulic Lash Adjusters with independent finger followers
Cylinder block components
The cylinder block components are described below:
Cylinder Block
The cylinders and crankcase are contained in a single cast iron construction. The cylinders are direct bored and
plateau honed with lubrication oil supplied via lubrication jets for piston and gudgeon pin lubrication and cooling. It is
not possible to rebore the cylinder block if the cylinders become worn or damaged. Three metal core plugs are fitted
to the three centre cylinders on the right hand side of the cylinder block.
Lubrication oil is distributed throughout the block via the main oil gallery to critical moving parts through channels
bored in the block which divert oil to the main and big-end bearings via oil holes machined into the crankshaft. Oil is
also supplied from the cylinder block main gallery to the five lubrication jets which cool and lubricate the piston and
gudgeon pins. Plugs are used to seal both ends of the main oil gallery at front and rear of the engine block. An oil
cooler is fitted to the LH side of the engine block; ports in the oil cooler assembly mate with ports in the cylinder block
to facilitate coolant flow. Oil is diverted through the oil cooler, centrifuge filter and full-flow filter before supplying the
main oil gallery. A tapping in the oil filter housing provides a lubrication source for the turbocharger bearings and an
oil pressure switch is included in a tapping in the oil cooler housing which determines whether sufficient oil pressure
is available to provide engine lubrication and cooling.
Cylinder cooling is achieved by water circulating through chambers in the engine block casting. A threaded coolant
jacket plug is located at the front RH side of the cylinder block.
Cast mounting brackets are bolted to both sides of the engine block for mounting the engine to the chassis on the LH
and RH hydramount studs.
The gearbox bolts directly to the engine block; a gearbox shim plate is located between the adjoining faces of the
gearbox and the flywheel side of the engine block and is fixed to the rear of the engine block by two bolts. Two hollow
metal dowels locate the rear of the cylinder block to the gearbox shim plate. The gearbox casing provides the
mounting for the starter motor.
A port is included at the rear left hand side of the cylinder block which connects to the turbocharger oil drain pipe to
return lubrication oil to the sump.
A plug sealing the lubrication cross-drilling gallery is located at the front right hand side of the cylinder block and plugs
for the main lubrication gallery is included at the front and rear of the cylinder block.

ENGINE - TD5
12-1-20 DESCRIPTION AND OPERATION
Oil pump
1Stiffener plate
2Ring dowel
3Outlet port
4Outer rotor
5Inner rotor6Spring dowel
7Oil pressure relief valve cap
8Oil pressure relief valve spring
9Oil pressure relief valve plunger
10Inlet port
The eccentric rotor oil pump is integrated with the stiffener plate and contains no serviceable parts except for the
pressure relief valve spring. The oil pump drive sprocket is attached to the front of the stiffener plate and is driven
through a chain and sprocket system.
A pressure relief valve is included at the outlet side of the oil pump to restrict oil pressure at high engine speeds by
recirculating oil through the relief valve back around the pump to the inlet. The relief valve and spring is a plunger type.
When oil pressure is great enough to lift the plunger, oil is allowed to escape past the plunger to relieve pressure and
prevent further rise.
Oil is delivered to the pump from the pick-up through a channel in the stiffener plate. The outlet side of the oil pump
delivers pressurised oil flow to the engine block main oil delivery gallery through a port in the stiffener plate.
Piston lubrication jets
Piston lubrication jets are fitted to the cylinder block to provide lubrication to the cylinder walls, and to the piston
underskirt for cooling the pistons and lubricating the gudgeon pins. The input port to each lubrication jet mates with a
port provided in each mounting position tapped at the underside of the cylinder block from the main oil delivery gallery.
When oil pressure is sufficient to supply flow through the jets, oil is squirted to the inside of the cylinder walls to provide
piston to wall lubrication and cooling and to the underside of the piston skirt at the bottom of the piston stroke (gallery
cooled piston). The squirt jets also provide splash feed lubrication supply to the small end bearings of the connecting
rods.
Each lubrication jet is fixed to a mounting position on the underside of the engine block by a single Torx screw.
Chain lubrication jet
A chain lubrication jet is located on the front face of the cylinder block, behind the front engine timing chain cover. The
inlet port to the lubrication jet mates with an oil supply port from the cylinder block main oil delivery gallery. The
lubrication jet is fixed to the front of the engine block by a single screw. Additional chain lubrication is provided by oil
supply through a small aperture tapped from the cylinder head oil delivery gallery.

ENGINE - TD5
12-1-26 DESCRIPTION AND OPERATION
Camshaft cover and engine cover components
The camshaft cover and engine cover components are described below:
Camshaft cover
The camshaft cover is cast from aluminium alloy and is fixed to the camshaft carrier/cylinder head assembly by 13
bolts. The cover has spacers and sealing washers inserted into each of the thirteen bolt holes.
A breather hose is connected to a port at the top of the camshaft cover by means of a hose clip which vents crankcase
gases back to the air intake via a breather valve in the air intake tract, located forward of the turbocharger in the
flexible air intake duct.
A rubber seal is fitted between the camshaft cover.
An oil filler aperture is included in the top of the camshaft cover, which is sealed with a plastic cap with integral rubber
seal.
Camshaft timing chain components
The timing chain cover and timing chain components are described below:
Timing chain cover
The timing chain cover is cast and machined aluminium alloy and is attached to the cylinder head by a bolt at the RH
top of the cover and by a stud and nut at the LH top of the cover. Eight screws are used to attach the timing chain
cover to the front of the engine block. The timing cover is located to the cylinder block front face by two dowels.
A viscous fan is attached to an idler pulley at the front of the engine block. The fan bearing is located on a shaft and
held in place by a circlip and a bearing flange, the inner race of the fan bearing is an interference fit on the shaft. The
fan idler pulley is attached to the bearing hub by three bolts, and the fan itself is secured to the pulley and bearing
shaft by a left hand threaded nut.

+ COOLING SYSTEM - Td5, DESCRIPTION AND OPERATION, Description.
The front of the crankshaft passes through a hole in the lower part of the timing cover. An oil seal is pressed into a
recess in the front of the timing cover to seal the interface between the front of the crankshaft and the timing cover.
A stub pipe is fitted to the front RH side of the timing cover which is used to attach the oil drain pipe from the vacuum
pump by means of a hose and spring clip.
Timing chains
The timing chain between the camshaft and crankshaft sprockets is a duplex type, each chain having 56 links. The
timing chain is contained between a fixed plastic guide and an hydraulically adjustable plastic tensioner arm which
are attached to the front of the engine block.
To cope with higher injection loads of the EU3 engine, the timing drive between the camshaft and crankshaft has been
upgraded. This requires thicker chain links to be used, therefore, the individual pre EU3 and EU3 components are not
interchangeable.
To distinguish between the two timing chains the links are different colours. A pre EU3 chain has blue links and a EU3
chain has bronze links.
The oil pump timing chain is a single type and traverses the oil pump sprocket and the rear crankshaft sprocket.
The timing chains are oil lubricated, with oil being provided by a chain lubrication jet and from oil flow returning back
to the sump from the cylinder head. An oil hole is included at the front left hand side of the cylinder head which supplies
oil from the cylinder head oil galleries.

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.

ENGINE - TD5
REPAIRS 12-1-39
Gasket - cylinder head
$% 12.29.02
Remove
Note: The following procedures cover engines
fitted with or without an EGR cooler. The EGR
cooler is bolted to the front of the cylinder head.
1.Remove bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.
2.Release turnbuckles and remove battery cover.
3.Disconnect battery earth lead.
4.Drain cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
5.Remove camshaft cover gasket.

+ ENGINE - Td5, REPAIRS, Gasket -
cover - camshaft.
6.Remove cooling fan coupling.

+ COOLING SYSTEM - Td5, REPAIRS,
Fan - viscous.
7.Remove 3 bolts and remove exhaust manifold
heat shield. 8.Remove turbocharger oil feed banjo bolt and
discard sealing washers.
9.Remove 3 nuts, release turbocharger from
exhaust manifold, discard gasket and tie
turbocharger aside.
10.Disconnect multiplugs from compressor, MAF
sensor, turbocharger wastegate modulator,
and AAP & IAT sensor.
11.Remove 2 bolts securing engine harness to
camshaft carrier.
12.Disconnect multiplug from EUI's and coolant
temperature sensor.

ENGINE - TD5
REPAIRS 12-1-43
11.Clean camshaft sprocket and mating face on
camshaft.
12.Ensure engine is set to TDC No. 1 cylinder and
mark on camshaft sprocket is positioned
between the 2 coloured links.
13.Position camshaft sprocket to camshaft; fit and
lightly tighten new bolts, then loosen bolts half
a turn.
14.Clean timing chain fixed guide retaining pin and
apply Loctite 242 to threads.
15.Fit timing chain fixed guide retaining pin and
tighten to 25 Nm (18 lbf.ft) .
16.Clean timing chain tensioner and fit new
sealing washer.
17.Fit timing chain tensioner and tighten to 45 Nm
(22 lbf.ft).
18.Tighten bolts securing camshaft sprocket to
camshaft to 37 Nm (27 lbf.ft).
19.Remove tool LRT-12-058 from camshaft.
20.Remove tool LRT-12-158 from gearbox bell
housing.
21.Fit new camshaft bore blanking plug and 'O'-
ring seal in recess in cylinder head.
22.Clean vacuum pump union.
23.Tighten union securing vacuum pump oil feed
pipe to cylinder head to 10 Nm (7 lbf.ft) .
24.Fit bolts securing alternator support bracket to
cylinder head and tighten to 25 Nm (18 lbf.ft) .
25.Connect top hose and heater hoses and secure
with clips.
26. Pre EU3 model:Fit bolt securing EGR pipe
clamp to cylinder head bolt and tighten to 10
Nm (7 lbf.ft) .
27. EU3 model: Connect coolant hoses to EGR
cooler and secure with the clips.
28.Position air intake hose to EGR valve and
tighten clip screw.
29.Disconnect fuel hose from connector block and
connect to fuel cooler.
30.Connect fuel hoses to fuel cooler and
connector block on cylinder head.
31.Connect coolant hoses to fuel cooler and
secure clips.
32.Connect vacuum hose to EGR valve.
33.Position engine harness and connect multi
plugs and glow plug connectors.
34.Fit and tighten bolts, engine harness to
camshaft carrier.
35.Clean exhaust manifold and turbocharger
interface.
36.Fit new gasket to exhaust manifold, position
turbocharger and tighten – nuts securing
turbocharger to manifold to 30 Nm (22 lbf.ft).
37.Clean turbocharger oil feed hose bolt.
38.Position turbocharger oil feed hose using new
sealing washers. Fit banjo bolt securing
turbocharger oil feed hose and tighten to 25 Nm
(18 lbf.ft) . 39.Position exhaust manifold heatshield and
tighten M6 bolts to 9 Nm (7 lbf.ft) and M8 bolt to
25 Nm (18 lbf.ft).
40.Fit cooling fan coupling.

+ COOLING SYSTEM - Td5, REPAIRS,
Fan - viscous.
41.Fit camshaft cover with new seal.

+ ENGINE - Td5, REPAIRS, Gasket -
cover - camshaft.
42.Refill cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
43.Connect battery earth lead.
44.Fit battery cover and secure fixings.
45.Fit bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.

ENGINE - TD5
12-1-44 REPAIRS
Rocker shaft assembly
$% 12.29.29
Remove
1.Remove cooling fan.

+ COOLING SYSTEM - Td5, REPAIRS,
Fan - viscous.
2.Remove camshaft cover gasket.

+ ENGINE - Td5, REPAIRS, Gasket -
cover - camshaft.
3.Loosen lock nuts and fully retract rocker
adjusting screws to prevent damage on
reassembly. 4.Rotate engine clockwise, until camshaft
sprocket and timing chain marks are aligned
and fit tool LRT-12-058 through camshaft
carrier to lock camshaft.
5.Progressively loosen then remove and discard
6 bolts securing rocker shaft assembly.
6.Remove and discard lock nuts and rocker
adjusting screws.

ENGINE - TD5
REPAIRS 12-1-45
Refit
1.Clean rocker shaft and mating faces.
CAUTION: If rockers or rocker shaft are to
be replaced, ensure replacements are
correct. Engine Serial No. Prefixes 10P to
14P are fitted with type A rocker arms and
shaft. Engine Serial No. Prefixes 15P to 19P
are fitted with type B rocker arms and shaft.
Type B rocker arms and shaft may be fitted
to Engine Serial No. Prefixes 10P to 14P as
an assembly.
2.Fit new rocker adjusting screws fully into rocker
arm. Fit new lock nuts to screws but do not
tighten.
CAUTION: Ensure screws are correct for
type of rocker arms fitted. Replacement
screws for Engine Serial No. Prefixes 15P to
19P have a centre punch mark adjacent to
the adjusting slot. These screws are not
interchangeable with those fitted to Engine
Serial No. Prefixes 10P to 14P.
3.Fit rocker shaft ensuring it is located on dowel.
4.Fit and progressively tighten new rocker shaft
bolts to 33 Nm (24 lbf.ft). 5.Before refitting the camshaft cover the
electronic injection unit (EUI) rockers must be
adjusted.
6.Remove tool LRT-12-058 from camshaft.
7.Rotate engine clockwise until No 1 injector lobe
is at full lift.
8.Rotate rocker adjusting screw clockwise until
the injector plunger is felt to bottom out.
9.Rotate rocker adjusting screw anti-clockwise
one complete turn to give plunger the required
bump clearance and tighten rocker arm
adjusting screw locknut to 16 Nm (12 lbf.ft) .
CAUTION: Ensure screw does not turn as
locknut is tightened.
10.Carry out above procedure for the remaining 4
rocker arms.
11.After completion of rocker arm adjustment,
slowly rotate engine clockwise 2 complete
turns by hand to ensure that no injectors are
bottoming out on their plungers.
12.Fit camshaft cover gasket.

+ ENGINE - Td5, REPAIRS, Gasket -
cover - camshaft.
13.Fit cooling fan coupling.

+ COOLING SYSTEM - Td5, REPAIRS,
Fan - viscous.

ENGINE - TD5
REPAIRS 12-1-47
Engine and ancillaries
$% 12.41.01
Remove
1.Remove bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.
2.Remove underbelly panel.

+ EXTERIOR FITTINGS, REPAIRS,
Panel - underbelly.
3.Drain engine oil.

+ MAINTENANCE, PROCEDURES,
Engine oil - diesel engine.
4.Remove radiator.

+ COOLING SYSTEM - Td5, REPAIRS,
Radiator.
5.Remove turbocharger.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Turbocharger.
6.Release clips and disconnect heater hoses
from fuel cooler and coolant rail.
7.Release clip and disconnect expansion tank
coolant hose from fuel cooler.
8.Disconnect fuel hoses, tank to fuel cooler and
connector block on cylinder head.
CAUTION: Always fit plugs to open
connections to prevent contamination.9.Disconnect fuel hose from fuel cooler and
secure to connector block on cylinder head.
This is to prevent contamination of the fuel
injection system.
10.Release servo vacuum pipe from clip on fuel
cooler and release hose from vacuum pump.
11.Release expansion tank from body mounting,
release clip, disconnect hose and remove tank.

ENGINE - TD5
12-1-52 REPAIRS
5.Fit 2 upper bolts securing engine oil cooler pipe
and gearbox housing to engine and tighten to
50 Nm (37 lbf.ft) .
6.Lower engine onto mountings, and tighten nuts
to 85 Nm (63 lbf.ft) .
7.Remove tool LRT-12-138 from engine.
8.Fit and tighten bolt securing engine closing
panel to gearbox.
9.Raise vehicle on ramp.
10.Fit nuts and bolts securing engine LH and RH
mountings to chassis and tighten to 85 Nm (63
lbf.ft).
11.Fit remaining bolts securing gearbox housing to
engine and tighten to 50 Nm (37 lbf.ft).
12.Rotate crankshaft and align drive plate to
torque converter.
13.Using a magnetic socket, fit and tighten new
torque converter drive plate bolts to 50 Nm (37
lbf.ft) .
14.Fit front cross member and tighten bolts to 26
Nm (19 lbf.ft).
15.Align gearbox oil cooler pipes.
16.Fit oil cooler pipe clip and tighten bolts to 9 Nm
(7 lbf.ft).
17.Position gearbox oil cooler pipe clamps and
tighten nuts.
18.Position coolant rail and secure support bracket
in engine LH and RH mounting brackets.
19.Fit starter motor.

+ CHARGING AND STARTING,
REPAIRS, Starter motor - diesel.
20.Lower ramp.
21.Position coolant rail to front chassis member, fit
and tighten bolt to 10 Nm (7 lbf.ft).
22.Connect heater hose to coolant rail and secure
with clip.
23.Connect hose to coolant pump and secure with
clip.
24.Position PAS pump and tighten bolts to 25 Nm
(18 lbf.ft).
25.Position PAS pump pulley and lightly tighten
bolts.
26.Position ACE pump, fit bolts and tighten to 25
Nm (18 lbf.ft).
27.Position A/C compressor, fit bolts and tighten
to 25 Nm (18 lbf.ft).
28.Position ancillary drive belt, rotate tensioner
anti-clockwise and locate belt to pulleys.
29.Tighten PAS pump pulley bolts to 10 Nm (7
lbf.ft).
30.Position air intake hose to air cleaner and
secure clips.
31.Position engine harness and connect
multiplugs to compressor, MAF sensor,
turbocharger boost solenoid, AAP & IAT
sensor.
32.Position air inlet hose to turbocharger and
tighten clip. 33.Connect hoses to turbocharger boost solenoid
and secure clips.
34.Clean CKP sensor and mating face.
CAUTION: If originally fitted: Fit spacer to
CKP sensor.
35.Using new 'O' ring, fit CKP sensor, tighten CKP
sensor bolt to 9 Nm (7 lbf.ft) and connect
multiplug.
36.Connect multiplug to EGR modulator.
37.Connect engine earth lead to battery earth lead
and tighten bolt.
38.Connect engine harness multiplug to ECM and
main harness.
39.Connect engine harness multiplugs to fuse
box.
40.Position glow plug lead to fusebox and secure
with bolt.
41.Position battery and alternator leads to fusebox
and secure with bolts.
42.Fit engine compartment fuse box cover.
43.Connect vacuum hose to EGR valve.
44.Connect hose to vacuum pump and secure
vacuum pipe to fuel cooler.
45.Disconnect fuel hose from connector block and
connect to fuel cooler.
46.Connect fuel hoses to fuel cooler and
connector block on cylinder head.
47.Position expansion tank, connect hose and
secure with clip. Secure tank to body mounting.
48.Connect coolant hoses to fuel cooler and
coolant rail and secure clips.
49.Fit turbocharger.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Turbocharger.
50. Fit radiator.

+ COOLING SYSTEM - Td5, REPAIRS,
Radiator.
51.Fill engine with oil.

+ MAINTENANCE, PROCEDURES,
Engine oil - diesel engine.
52.Fit underbelly panel.

+ EXTERIOR FITTINGS, REPAIRS,
Panel - underbelly.
53.Fit bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.