turbo LAND ROVER DISCOVERY 2002 Workshop Manual

CONTENTS
CONTENTS 7
Operation ........................................................................................................................................ 18-1-38
ADJUSTMENTS
Glow plug ....................................................................................................................................... 18-1-45
REPAIRS
Engine control module (ECM) ........................................................................................................ 18-1-47
Sensor - engine coolant temperature (ECT) ................................................................................. 18-1-47
Sensor - crankshaft (CKP) .............................................................................................................. 18-1-48
Air filter assembly ........................................................................................................................... 18-1-48
Element - air filter ............................................................................................................................ 18-1-49
Sensor - fuel temperature .............................................................................................................. 18-1-50
Sensor - mass air flow (MAF) ....................................................................................................... 18-1-51
Sensor - combined MAP and IAT ................................................................................................. 18-1-51
Sensor - ambient air pressure (AAP) ............................................................................................ 18-1-52
Element - fuel filter ........................................................................................................................ 18-1-53
Cooler - fuel .................................................................................................................................. 18-1-53
Sensor - Throttle position (TP) ........................................................................................................ 18-1-54
Turbocharger ................................................................................................................................ 18-1-55
Intercooler ..................................................................................................................................... 18-1-56
Valve - solenoid boost control ........................................................................................................ 18-1-58
Regulator - fuel pressure .............................................................................................................. 18-1-59
Glow plugs ...................................................................................................................................... 18-1-60
Injectors .......................................................................................................................................... 18-1-61
Switch - cruise control (on/off) ........................................................................................................ 18-1-62
Switch - cruise control (set/resume) ................................................................................................ 18-1-63
Switch - clutch ................................................................................................................................. 18-1-63
ENGINE MANAGEMENT SYSTEM - V8 .................................................. 18-2-1
DESCRIPTION AND OPERATION
Engine management component location - Passenger compartment ............................................ 18-2-2
Engine management component location - Engine compartment .................................................. 18-2-3
Engine management block diagram ............................................................................................... 18-2-4
Description - engine management .................................................................................................. 18-2-6
Operation - engine management .................................................................................................... 18-2-43
DESCRIPTION AND OPERATION
Cruise control component layout .................................................................................................... 18-2-55
Cruise control block diagram .......................................................................................................... 18-2-56
Description - cruise control ............................................................................................................. 18-2-57
Operation - cruise control................................................................................................................ 18-2-66
ADJUSTMENTS
Cable - throttle ............................................................................................................................. 18-2-69
Cable - cruise control .................................................................................................................... 18-2-69
REPAIRS
Spark plugs .................................................................................................................................. 18-2-71
Coil - ignition ................................................................................................................................. 18-2-71
Engine control module (ECM) ......................................................................................................... 18-2-72
Sensor - engine coolant temperature (ECT) ................................................................................ 18-2-73
Sensor - crankshaft position (CKP) ............................................................................................... 18-2-74
Sensor - radiator temperature ....................................................................................................... 18-2-75
Sensor - camshaft position (CMP) ................................................................................................. 18-2-76

GENERAL DATA
04-1
GENERAL DATA
Engine - Td5
General
Type 2.5 litre in-line direct injection diesel, turbocharged and intercooled
Cylinder arrangement 5 in-line, No. 1 cylinder at front of engine
Bore 84.450 mm (3.3248 in)
Stroke 88.950 mm (3.5020 in)
Capacity 2498 cm
3 (152.5 in3)
Firing order 1 - 2 - 4 - 5 - 3
Compression ratio 19.5 : 1
Direction of rotation Clockwise viewed from the front of the engine
Dimensions:

Length 766 mm (30.1 in)

Width 708 mm (27.8 in)

Height 788 mm (31.0 in)
Injection timing Controlled by ECM
Injectors:

Make/Type Lucas EV1

Nominal operating pressure:

Pre EU3 models 1500 bar (21750 lbf.in
2)

EU3 models 1750 bar (25500 lbf.in
2)
Maximum governed speed 4850 rev/min
Maximum overrun speed 5460 rev/min
Idle speed:

Manual gearbox 740 ± 50 rev/min

Automatic gearbox 760 ± 50 rev/min
Glow plugs Beru 12 V. Four plugs in cylinders 1, 2, 3 and 4
Turbocharger Garrett GT 20
Emissions standard:

Pre EU3 models ECD 2

EU3 models ECD 3
Valve timing
Inlet valves:

Opens 14° BTDC

Closes 33° ABDC
Exhaust valves:

Opens 57° BBDC

Closes 14° ATDC

TORQUE WRENCH SETTINGS
06-3
Rocker shaft bolts 32 Nm (24 lbf. ft)
Timing chain adjustable guide bolt 25 Nm (18 lbf.ft)
Timing chain cover bolts 27 Nm (20 lbf.ft)
Timing chain cover to cylinder block stud 7 Nm (5.2 lbf.ft)
Timing chain fixed guide retaining pin 25 Nm (18 lbf.ft)
Timing chain cover to cylinder head nut and bolt 25 Nm (18 lbf.ft)
Timing chain fixed guide (M6) bolt 10 Nm (7 lbf.ft)
Timing chain fixed guide (M10) bolt 45 Nm (33 lbf.ft)
Timing chain lubrication jet bolt 10 Nm (7 lbf.ft)
Timing chain tensioner 45 Nm (33 lbf.ft)
Torque converter to drive plate (automatic transmission) bolts 50 Nm (37 lbf.ft)
Turbocharger heatshield bolts 10 Nm (7 lbf.ft)
Turbocharger oil feed pipe banjo bolt 25 Nm (18 lbf.ft)
Turbocharger to exhaust manifold nuts 30 Nm (22 lbf.ft)
Vacuum pump oil feed pipe to cylinder head union 10 Nm (7 lbf.ft)
Viscous fan nut45 Nm (33 lbf.ft)
Fuel spill return pipe unions - if fitted 20 Nm (15 lbf.ft)TORQUE DESCRIPTION METRIC IMPERIAL

TORQUE WRENCH SETTINGS
06-5
Emission control - Td5
Emission control - V8
Engine management system - Td5
TORQUE DESCRIPTION METRIC IMPERIAL
EGR valve pipe Allen screws 10 Nm (7 lbf.ft)
EGR valve to inlet manifold bolts 10 Nm (7 lbf.ft)
EGR intake pipe clip to cylinder head bolts - if fitted 25 Nm (18 lbf.ft)
EGR cooler to cylinder head nut and bolts - if fitted 25 Nm (18 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
HO
2S Sensors45 Nm (33 lbf.ft)
SAI air manifold union nuts 25 Nm (18 lbf.ft)
Rubber mountings to SAI pump bracket 10 Nm (7 lbf.ft)
SAI control valve to manifold bolts 10 Nm (7 lbf.ft)
SAI pump to bracket nuts 10 Nm (7 lbf.ft)
SAI pump bracket to body bolt 20 Nm (15 lbf.ft)
Vacuum reservoir to mounting bracket bolt 10 Nm (7 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
ECT sensor15 Nm (11 lbf.ft)
Fuel tank cradle45 Nm (33 lbf.ft)
CKP sensor10 Nm (7 lbf.ft)
MAP and IAT sensor 10 Nm (7 lbf.ft)
Fuel cooler to inlet manifold - upper bolts 25 Nm (18 lbf.ft)
Turbocharger to exhaust manifold 30 Nm (22 lbf.ft)
Turbocharger drain pipe 10 Nm (7 lbf.ft)
Banjo bolt to oil feed pipe 25 Nm (18 lbf.ft)
Fuel temperature sensor 14 Nm (10 lbf.ft)
Pressure regulator 25 Nm (18 lbf.ft)
Glow plugs16 Nm (12 lbf.ft)
EUI clamp bolts32 Nm (24 lbf.ft)
EGR valve to exhaust manifold 10 Nm (7 lbf.ft)
EGR valve to inlet manifold 10 Nm (7 lbf.ft)
EGR clip25 Nm (18 lbf.ft)

TORQUE WRENCH SETTINGS
06-6
Engine management system - V8
Cooling system
Manifolds and exhaust systems - Td5
TORQUE DESCRIPTION METRIC IMPERIAL
Spark plugs20 Nm (15 lbf.ft)
Fuel tank cradle45 Nm (33 lbf.ft)
ECT sensor10 Nm (7 lbf.ft)
CKP sensor6 Nm (4.4 lbf.ft)
CMP sensor8 Nm (6 lbf.ft)
KS sensor22 Nm (16 lbf.ft)
Throttle body10 Nm (7 lbf.ft)
Plenum chamber22 Nm (16 lbf.ft)
Breather adaptor6 Nm (4.4 lbf.ft)
Throttle cable abutment bracket 10 Nm (7 lbf.ft)
TP sensor 2.2 Nm (1.6 lbf.ft)
IACV sensor8 Nm (6 lbf.ft)
HO
2S sensor45 Nm (33 lbf.ft)
Ignition coils8 Nm (6 lbf.ft)
Fuel rail9 Nm (7 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
Cylinder block drain plug 30 Nm (22 lbf.ft)
Coolant pump24 Nm (18 lbf.ft)
Coolant pump pulley 22 Nm (16 lbf.ft)
Coolant pump cover - Td5 10 Nm (7 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
Front pipe to turbocharger 27 Nm (20 lbf.ft)
Inlet manifold25 Nm (18 lbf.ft)
Tail pipe25 Nm (18 lbf.ft)
Fuel cooler25 Nm (18 lbf.ft)
EGR valve10 Nm (7 lbf.ft)
Exhaust manifold25 Nm (18 lbf.ft)
Exhaust manifold heatshield (M6) bolts 10 Nm (7 lbf.ft)
Exhaust manifold heatshield (M8) bolts 25 Nm (18 lbf.ft)
EGR pipe Allen screws 10 Nm (7 lbf.ft)

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
DESCRIPTION AND OPERATION 12-1-17
1Full-flow filter housing
2Thermostat
3Roll-pin
4Port – feed line to turbocharger
5Outlet port from full-flow filter (> 74
° C)
6Inlet port to full-flow filter
7Outlet port from full-flow filter (< 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.

ENGINE - TD5
12-1-18 DESCRIPTION AND OPERATION
Oil filter housing thermostat
1Circlip
2Thermostat end cap
3Oil seal
4Thermostatic valve
5Return spring
6Oil filter housing
7Threaded 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 following table indicates approximate values for thermostat plunger travel against temperature:
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 psi) is experienced.
Thermostat plunger travel mm (in.) Oil temperature °C
0 (0) < 74 °C
5 (0.20) 80 °C
12 (0.47) 90 °C
16 (0.63) 130 °C

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
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.