2002 LAND ROVER DISCOVERY length

ENGINE - TD5
12-1-62 REPAIRS
Valve - relief - oil pressure
$% 12.60.56
Remove
1.Remove sump gasket.

+ ENGINE - Td5, REPAIRS, Gasket -
sump.
2.Remove and discard plug from oil pump
housing.
3.Remove spring and valve.
Refit
1.Clean valve, spring and plug.
2.Clean valve seating inside oil pump housing.
3.Check valve and bore for scoring and
corrosion. Light scoring may be removed using
grade 600 emery cloth soaked in oil.
4.Check spring for distortion, check free length of
spring: Spring free length = 42.00 mm (1.65 in).
CAUTION: Renew relief valve as an
assembly.
5.Lubricate valve and seating.
6.Fit valve and spring to pump.
7.Apply Loctite 243 sealant to threads of new
plug.
CAUTION: Do not attempt to fit original
plug.
8.Fit oil pump pressure relief valve plug and
tighten to 23 Nm (17 lbf.ft).
9.Fit sump gasket.

+ ENGINE - Td5, REPAIRS, Gasket -
sump.
10.Check engine oil level, top-up if necessary.
Switch - oil pressure
$% 12.60.50
Remove
1.Remove fixings and remove engine acoustic
cover.
2.Remove 3 bolts and remove exhaust manifold
heat shield.
3.Disconnect multiplug from oil pressure switch.
4.Position container below switch to catch oil
spillage.
5.Remove oil pressure switch from oil cooler
housing.

ENGINE - TD5
OVERHAUL 12-1-79
24.Compare figures obtained with camshaft
bearing clearance:
lCamshaft bearing clearance = 0.04 to 0.10
mm (0.002 to 0.004 in)
25.If any bearing clearance is found to exceed
figures given, repeat the above procedures
using a new camshaft. If, after repeating the
clearance check using a new camshaft the
clearances are still excessive, a new cylinder
head and camshaft carrier assembly must be
fitted.
26.Remove all traces of Plastigage using an oily
cloth, do not use a scraper.
27.On completion, discard camshaft carrier bolts.
28.Check free length of valve springs:
lFree length = 46.75 to 47.25 mm (1.84 to
1.86 in)
29. Replace valve springs as a set, if springs
are to be refitted, keep them in their fitted
order.
30.Clean carbon from valves, check valves for
burning, pitting or cracking; replace as
necessary.
31.Clean carbon from valve seat inserts, remove
all loose particles on completion.
32.Check valve seat inserts for pitting and burning.
It is not permissible to recut or replace valve
seat inserts.
33.Remove carbon deposits from valve guides
using tool LRT-12-186 inserted from the
combustion chamber face side of cylinder
head. Ensure all loose particles of carbon are
removed on completion.
34.Check and record diameter of each valve stem:
lValve stem diameter - Inlet = 6.907 to 6.923
mm (0.2719 to 0.2725 in)
lValve stem diameter - Exhaust = 6.897 to
6.913 mm (0.2715 to 0.2721 in)35.Renew any valve if stem diameter is less than
specified.
36.Check and record valve stem to guide
clearance using the following procedures.
37.Insert each valve into its respective guide.
38.Extend valve head 10 mm (0.375 in) out of
valve seat and position a DTI gauge to rear of
valve head.
39.Move valve towards front of cylinder head and
zero DTI gauge ensuring that stylus of gauge
remains in contact with valve head.
40.Move valve towards rear of cylinder head,
record gauge reading to give valve stem to
guide clearance:
lInlet valve = 0.025 to 0.059 mm (0.0009 to
0.0023 in)
lExhaust valve = 0.035 to 0.069 mm (0.0013
to 0.0027 in)
41.If stem to guide clearance exceeds figures
given and valve stem diameters were as
specified, cylinder head assembly must be
replaced; it is not possible to replace valve
guides.
42.Repeat above procedures for remaining valves.
Keep valves in their fitted order.
43.Check face angle of each valve, renew any
valve with incorrect face angles, do not attempt
to recut.
lValve face angle - inlet = 29
° 48' ± 12'
lValve face angle - exhaust = 44
° 48' ± 12'
44.Lap each valve to its seat using grinding paste.
45.Apply Prussion Blue to valve seat, insert valve
into guide and press it firmly, without rotating
on to seat.
46.Remove valve and check that a continuous,
even line of Prussian Blue has been
transferred on to valve face. Note that line
does not have to be across whole width of
valve face.
47.Remove all traces of grinding paste on
completion.
48.Check valve head stand down using the
following procedures.

ENGINE - TD5
12-1-92 OVERHAUL
9.Place a straight edge across pump body and
using feeler gauges, measure end-float of
outer rotor:
lOuter rotor end-float = 0.038 to 0.075 mm
(0.0001 to 0.003 in)
10.Check drive shaft bush in pump cover for signs
of scoring and wear.
11.Renew oil pump and stiffener plate assembly if
excessive scoring or wear exists.
12.Lubricate pump rotors and drive shaft bush with
engine oil.
13.Fit rotors ensuring reference marks are aligned
and identification mark on outer rotor is facing
outwards.
14.Fit cover to pump, fit 5 new screws and tighten
by diagonal selection to 6 Nm (4.5 lbf.ft).
15.Remove and discard oil pressure relief valve
plug.
16.Remove spring and relief valve plunger.
17.Clean valve plunger and spring.
18.Check valve plunger and relief valve bore for
scoring and corrosion, light scoring and
corrosion may be removed using grade 600
emery cloth soaked in oil.19.Check spring for distortion, check free length of
spring:
lSpring free length = 42.0 mm (1.65 in)
20.Lubricate valve plunger and seating.
21.Fit valve plunger and spring to oil pump.
22.Apply Loctite 243 sealant to threads of a new
plug. Do not attempt to fit original plug.
23.Fit plug and tighten to 23 Nm (17 lbf.ft).
Reassembly
1.Clean mating faces of oil pump, stiffener plate
assembly and cylinder block; ensure bolt and
dowel holes are clean and dry.
2.Lubricate a new 'O' ring with engine oil and fit to
oil pump housing outlet.
3.Position oil pump and stiffener plate assembly
on to cylinder block ensuring 2 dowels are
correctly located.
4.Fit new bolts and using sequence shown,
tighten to 13 Nm (10 lbf.ft).
5.Lubricate a new 'O' ring with engine oil and fit to
oil pick-up strainer.
6.Clean threads of oil pick-up strainer Torx
screws and apply Loctite 242 to screw
threads.
7.Fit oil pick-up strainer, fit Torx screws and
tighten to 10 Nm (8 lbf.ft).
8.Position oil pump drive sprocket to chain and oil
pump ensuring that the 'D' shape on the drive
sprocket is located on the flat on the oil pump
drive shaft.
9.Clean oil pump drive sprocket retaining bolt and
apply Loctite 242 to bolt threads.
10.Fit oil pump drive sprocket and tighten bolt to
25 Nm (18 lbf.ft).
11.Fit new sump gasket.

+ ENGINE - Td5, OVERHAUL, Gasket
- engine sump.

ENGINE - V8
OVERHAUL 12-2-63
6.Remove carbon deposits from exhaust valve
guide using a 8.70 mm (0.34 in) diameter
reamer inserted from combustion face side of
cylinder head.
NOTE: Modified inlet valves, exhaust valves
and valve guides were fitted to 4.0 litre engines
from the following engine numbers: 55D
05678A; 56D 50788A and 97D 05505A and are
fitted to all 4.6 litre engines.
7.Modified inlet valves may be identified by
measuring the distance 'A' from the valve head
face to the top of the undercut on the valve
stem:
lEarly valves = 29.5 to 30.5 mm (1.16 to 1.20
in)
lLater valves = 32.5 to 33.5 mm (1.28 to 1.32
in)8.Modified exhaust valves may be identified as
follows:
lEarly valves 'A' – Chrome finish
lLater valves 'B' – Black nitrided finish
9.Modified valve guides are 5 mm (0.211 in)
shorter than the early type, the overall length is
now 57 mm (2.24 in); the reduction in length
being the distance the guide protrudes into the
combustion chamber side of the cylinder head.
NOTE: The modified valves and guides may be
fitted to 4.0 litre engines prior to the above
numbers in cylinder sets. Early type valves will
continue to be supplied for early 4.0 litre
engines but if valve guides are found to be
worn, the later valves and guides must be fitted.

ENGINE - V8
12-2-64 OVERHAUL
10.Check the following valve dimensions. Renew
valves as necessary.
lValve head diameter 'A': Inlet = 39.75 to
40.00 mm (1.56 to 1.57 in).
lValve head diameter 'A': Exhaust = 34.23 to
34.48 mm (1.35 to 1.36 in).
lValve stem diameter 'B': Inlet = 8.664 to
8.679 mm (0.341 to 0.342 in).
lValve stem diameter 'B': Exhaust – 4.0 litre
engines up to engine nos. 55D 05677A; 56D
50787A and 97D 05504A = 8.651 to 8.666
mm (0.340 to 0.341 in).
lValve stem diameter 'B': Exhaust – 4.0 litre
engines from engine nos. 55D 05678A; 56D
50788A and 97D 05505A and all 4.6 litre
engines = 8.641 to 8.656 mm (0.340 to
0.341 in)
11.Check installed height of valve.
lValve installed height, end of valve to base
of spring seat, 'C' = 44.163 to 45.288 mm
(1.741 to 1.802 in).12.Check condition of valve springs. Valve
springs must be replaced as a complete
set.
lValve spring free length = 48.30 mm (1.90
in).
lValve spring fitted length = 40.40 mm (1.59
in).
l Spring load - valve closed = 339
± 10 N (76
± 2.25 lbf).
lSpring load - valve open = 736
± 10 N (166
± 2.25 lbf).
13.Check valve stem to guide clearance using the
following procedures:
14.Insert each valve into its respective guide.
15.Extend valve head approximately 13 mm (0.6
in) out of valve seat and position a DTI gauge
to rear of valve head.
16.Move valve towards front of cylinder head and
zero DTI gauge ensuring that stylus of gauge
remains in contact with valve head.
17.Move valve towards rear of cylinder head and
record gauge reading to give valve stem to
guide clearance.
l Valve stem to guide clearance 'D': Inlet =
0.025 to 0.066 mm (0.001 to 0.002 in).
l Valve stem to guide clearance 'D': Exhaust
– 4.0 litre engines up to engine nos. 55D
05677A; 56D 50787A; 97D 05504A = 0.038
to 0.078 mm (0.0015 to 0.003 in).
lValve stem to guide clearance 'D': Exhaust
– 4.0 litre engines from engine nos. 55D
05678A; 56D 50788A; 97D 05505A and all
4.6 litre engines = 0.048 to 0.088 mm
(0.0019 to 0.0035 in).
18.Renew valve guides as necessary.
19.Using valve guide remover tool LRT-12-037
press valve guide into combustion face side of
cylinder head.

ENGINE - V8
12-2-68 OVERHAUL
Inspect
1.Clean carbon from piston. Inspect piston for
distortion, cracks and burning.
2.Remove piston rings from piston.
3.Measure and record piston diameter at 90
° to
gudgeon pin axis and 10 mm (0.4 in) from
bottom of the skirt. The piston must be 0.02 to
0.045 mm (0.001 to 0.002 in) smaller than the
cylinder bore.
4.Check gudgeon pin bore in piston for signs of
wear and overheating.
5.Pistons fitted on production are graded 'A' or
'B', the grade letter is stamped on the piston
crown.
lPiston diameter: Grade 'A' = 93.970 to
93.985 mm (3.6996 to 3.7002 in).
lPiston diameter: Grade 'B' = 93.986 to 94.00
mm (3.7002 to 3.7007 in).
6.Worn cylinders fitted with grade 'A' pistons may
be honed to accept the grade 'B' piston
provided that specified cylinder bore and
ovality limits are maintained. Grade 'B'
pistons are supplied as service
replacements. Do not attempt to de-glaze
cylinder bores.
7.Check gudgeon pins for signs of wear and
overheating.
8.Check clearance of gudgeon pin in piston.
l Gudgeon pin to piston clearance = 0.006 to
0.015 mm (0.0002 to 0.0006 in).
9.Check overall dimensions of gudgeon pin.
Gudgeon pins are only supplied as an
assembly with replacement pistons.
lGudgeon pin length = 60.00 to 60.50 mm
(2.362 to 2.382 in).
lGudgeon pin diameter = 23.995 to 24.00
mm (0.9446 to 0.9448 in)10.Measure cylinder bore wear and ovality in two
axis 40 to 50 mm (1.6 to 2 in) from top of bore.
The temperature of piston and cylinder
block must be the same to ensure accurate
measurement. Do not attempt to de-glaze
cylinder bores.
lGrade 'A' pistons: Cylinder bore = 94.00 to
94.015 mm (3.7007 to 3.7013 in).
lGrade 'B' pistons: Cylinder bore = 94.016 to
94.030 mm (3.7014 to 3.7019 in).
lMaximum ovality = 0.013 mm (0.0005 in).
11.Check alignment of connecting rods.
Reassembly
1.Pistons have a 5 mm (0.2 in) offset gudgeon pin
which can be identified by an arrow mark on
the piston crown. This arrow must always point
towards the front of the engine.
2.Assemble pistons to connecting rods with
arrow on piston pointing towards domed
shaped boss on connecting rod for RH bank of
cylinders and arrow pointing away from domed
shaped boss for LH bank of cylinders.

EMISSION CONTROL - V8
17-2-28 DESCRIPTION AND OPERATION
The SAI pump is attached to a bracket at the rear RH side of the engine compartment and is fixed to the bracket by
three studs and nuts. The pump is electrically powered from a 12V battery supply via a dedicated relay and supplies
approximately 35kg/hr of air when the vehicle is at idle in Neutral/Park on a start from 20
°C (68°F).
Air is drawn into the pump through vents in its front cover and is then passed through a foam filter to remove
particulates before air injection. The air is delivered to the exhaust manifold on each side of the engine through a
combination of plastic and metal pipes.
The air delivery pipe is a flexible plastic type, and is connected to the air pump outlet via a plastic quick-fit connector.
The other end of the flexible plastic pipe connects to the fixed metal pipework via a short rubber hose. The part of the
flexible plastic pipe which is most vulnerable to engine generated heat is protected by heat reflective sleeving. The
metal delivery pipe has a fabricated T-piece included where the pressurised air is split for delivery to each exhaust
manifold via the SAI control valves.
The pipes from the T-piece to each of the SAI control valves are approximately the same length, so that the pressure
and mass of the air delivered to each bank will be equal. The ends of the pipes are connected to the inlet port of each
SAI control valve through short rubber hose connections.
The T-piece is mounted at the rear of the engine (by the ignition coils) and features a welded mounting bracket which
is fixed to the engine by two studs and nuts.
The foam filter in the air intake of the SAI pump provides noise reduction and protects the pump from damage due to
particulate contamination. In addition, the pump is fitted on rubber mountings to help prevent noise which is generated
by pump operation from being transmitted through the vehicle body into the passenger compartment.
If the secondary air injection pump malfunctions, the following fault codes may be stored in the ECM diagnostic
memory, which can be retrieved using 'Testbook':
Secondary air injection (SAI) pump relay
The secondary air injection pump relay is located in the engine compartment fusebox. The engine control module
(ECM) is used to control the operation of the SAI pump via the SAI pump relay. Power to the coil of the relay is supplied
from the vehicle battery via the main relay and the ground connection to the coil is via the ECM.
Power to the SAI pump relay contacts is via fusible link FL2 which is located in the engine compartment fusebox.
P-code Description
P0418Secondary air injection pump powerstage fault (e.g. - SAI pump relay fault / SAI
pump or relay not connected / open circuit / harness damage).

ENGINE MANAGEMENT SYSTEM - TD5
18-1-28 DESCRIPTION AND OPERATION
Exhaust Gas Regulator (EGR) modulator
The EGR modulator is located in the engine compartment on the offside inner wing. It regulates the vacuum source
to the EGR valve allowing it to open or close. The ECM utilises the EGR modulator to control the amount of exhaust
gas being recirculated in order to reduce exhaust emissions and combustion noise. Optimum EGR is usually obtained
when the vehicle is operating at light throttle openings, and the vehicle is cruising at approximately 2000 to 3000 rev/
min.
Input/Output
The EGR modulator receives battery voltage from fuse 2 in the engine compartment fuse box. The earth path is via
pin 3 of ECM connector C0158. The length of time that the ECM supplies an earth is how long the exhaust gases are
allowed to recirculate. The ECM decides how long to supply the earth for by looking at engine temperature and engine
load.
The EGR can fail in the following ways:
lSolenoid open circuit.
lShort circuit to vehicle supply.
lShort circuit to earth.
In the event of an EGR modulator failure the EGR system will become inoperative.
The MIL will not illuminate in the event of an EGR modulator failure.