LAND ROVER DISCOVERY 1999 Workshop Manual

ENGINE - V8
12-2-66 OVERHAUL
26.Remove worn valve seat.
CAUTION: Take care not to damage the
counterbore in the cylinder head when
removing valve seats.
27.Heat cylinder head evenly to approximately
120° C (250°F).
WARNING: Handle the hot cylinder head
with care.
28.Using a suitable mandrel, press new insert fully
into counterbore.
29.Allow cylinder head to air cool.
CAUTION: Renew worn valve guides and/or
valve seats before lapping the valves.
30.Recut valve seat in head and lap in valves
using fine paste.
31.Coat valve with a small quantity of engineer's
blue, insert valve and press into position
several times without rotating. Seating position
should be in centre of valve face. 32.Check valve installed height if valve seats have
been refaced or renewed.
lValve installed height, end of valve to base
of spring seat, 'A' = 44.16 to 45.29 mm (1.74
to 1.80 in).
33.Reface valves as necessary. If a valve has to
be ground to a knife-edge to obtain a true seat,
renew valve.
34.Cut valve seats using suitable cutters:
lValve seat angle 'A' = 45°.
lValve seat insert diameter 'B' Inlet = 36.83
mm (1.45 in).
lValve seat insert diameter 'B' Exhaust =
31.50 mm (1.24 in).
lSeating width 'C' - Inlet = 0.89 to 1.4 mm
(0.035 to 0.055 in).
lSeating width 'C' - Exhaust = 1.32 to 1.83
mm (0.052 to 0.072 in).
lAngle 'D' = 70° .
lAngle 'E' = 46° to 46° 25'.
lAngle 'F' = 20° .

ENGINE - V8
OVERHAUL 12-2-67
35. Check that cutter blades are adjusted so that
middle of blade contacts area of material to be
cut. Use light pressure and only remove the
minimum of material necessary.
36.Clean valve seat and valve.
Reassembly
1.Clean spring caps, collets and valve springs.
2.Lubricate new valve stem oil seal with clean
engine oil and fit seal.
3.Lubricate valve with clean engine oil and fit
valve.
4.Fit spring and cap, compress spring using tool
LRT-12-034 and fit collets.
5.Release valve spring and remove tool LRT-12-
034.
6.Fit cylinder head gasket.

+ ENGINE - V8, OVERHAUL, Gasket -
cylinder head.
Piston assemblies
$% 12.17.02.01
Disassembly
1.Remove cylinder head.

+ ENGINE - V8, OVERHAUL, Gasket -
cylinder head.
2.Remove oil pick-up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.
3.Suitably identify each connecting rod and
piston assembly to its respective cylinder bore.
4.Remove 2 bolts securing each connecting rod
bearing cap.
5.Remove connecting rod bearing cap and
collect connecting rod bearings.
6.Remove ridge of carbon from top of cylinder
bores.
7.Carefully push each piston assembly from the
top of the cylinder.
CAUTION: Ensure that connecting rods do
not contact cylinder bores.
8.Refit bearing cap onto connecting rod, lightly
tighten dowel bolts.
9.Suitably identify each piston to its respective
connecting rod.

ENGINE - V8
12-2-68 OVERHAUL
10.Position body of tool LRT-12-013 in vice.
11.Screw large nut back until flush with end of
centre screw.
12.Push centre screw forward until nut contacts
thrust race.
13.Position remover/replacer LRT-12-126/2 in
LRT-12-013 with its long spigot inside bore of
hexagon body.
14.Locate piston and connecting rod assembly on
centre screw and up to remover/replacer
adapter tool LRT-12-126/2.
CAUTION: Ensure that prongs of remover/
replacer adapter LRT-12-162/2 remain in
contact with piston and do not contact
gudgeon pin.
15.Fit remover/replacer bush LRT-12-126/1 on
centre screw with flanged end facing away from
gudgeon pin.
CAUTION: Ensure that remover/replacer
bush LRT-12-126/1 is correctly located in
gudgeon pin bore of piston.
16.Screw stop nut onto centre screw.
17.Lock the stop nut securely with the lock screw.
18.Push connecting rod to locate end of gudgeon
pin in remover/replacer adapter LRT-12-126/2.
19.Ensure remover/replacer bush LRT-12-126/1
is located in gudgeon pin bore of piston.
20.Screw large nut up to tool LRT-12-013.
21.Hold lock screw and turn large nut until
gudgeon pin is withdrawn from piston.
CAUTION: Ensure that prongs of tool LRT-
12–126/2 remain in contact with piston and
do not contact the gudgeon pin.
22.Dismantle tool LRT-12-013 and remove piston,
connecting rod and gudgeon pin. 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 0.015 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.
CAUTION: Ensure replacement pistons are
correct for the compression ratio of the
engine. The compression ratio will be found
on the cylinder block adjacent to the engine
serial number.
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).

ENGINE - V8
OVERHAUL 12-2-69
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.
3.Clamp hexagon body of tool LRT-12-013 in
vice.
4.Screw large nut back until flush with end of
centre screw.
5.Locate remover/replacer adapter LRT-12-126/
2 with its long spigot inside bore of hexagon
body.
6.Fit parallel sleeve, part of tool LRT-12-013,
ensuring that grooved end is towards open end
of tool LRT-12-013. Position sleeve up to
shoulder of centre screw.
7.Lubricate gudgeon pin and bores of connecting
rod and piston with graphite oil.
8.Locate connecting rod and piston to centre
screw with connecting rod entered on parallel
sleeve, part of LRT-12-013 up to the machined
groove on the sleeve.

ENGINE - V8
12-2-70 OVERHAUL
9.Fit gudgeon pin on to centre screw and into
piston bore up to connecting rod.
10.Fit remover/replacer bush LRT-12-126/1 with
flanged end towards gudgeon pin.
11.Screw the stop nut on to centre screw and
position piston against groove of tool LRT-12-
126/2.
CAUTION: Ensure that prongs of tool LRT-
12–126/2 remain in contact with piston and
do not contact gudgeon pin.
12.Lock the stop nut securely with the lockscrew.
13.Lubricate centre screw threads and thrust race
with graphite oil, screw large nut up to tool
LRT-12-013.
14.Set torque wrench to 16 Nm (12 lbf.ft) and using
socket on large nut, pull gudgeon pin in until
flange of remover/replacer bushLRT-12-126/1
is 0.40 mm (0.016 in), dimension 'A' from
face of piston. If torque is exceeded during this
procedure, fit of gudgeon pin to connecting rod
is not acceptable and components must be
replaced.
CAUTION: The centre screw and thrust race
must be kept well lubricated throughout the
operation.
15.Dismantle tool, remove piston and check no
damage has occurred during pressing and that
piston moves freely on gudgeon pin.
16.Remove compression rings, oil control rails
and expander from new piston.
17.Invert piston and with arrow pointing towards
rear of cylinder block, insert piston into cylinder
liner.
18.Position piston with bottom of skirt 30 mm (1.12
in) from top cylinder liner. 19.Using feeler gauges, measure and record
clearance between piston and left hand side of
cylinder- viewed from the front of cylinder
block.
lPiston to bore clearance = 0.020 to 0.045
mm (0.001 to 0.002 in).
20.Insert piston rings into cylinder bore, use the
piston to hold the rings square to bore and
check the ring gap.
l1st compression ring = 0.30 to 0.50 mm
(0.012 to 0.02 in).
l2nd compression ring = 0.40 to 0.65 mm
(0.016 to 0.026 in).
lOil control ring rails = 0.38 to 1.40 mm
(0.015 to 0.055 in).
21.Remove piston rings from bore.
22.Fit oil control ring rails and expander, ensuring
ends butt and do not overlap.
23.Fit 2nd compression ring marked 'TOP' with
marking uppermost in 2nd groove.
24.Fit 1st compression ring in first groove either
way round.
25.Check piston ring to groove clearance.
l1st compression ring = 0.05 to 0.10 mm
(0.002 to 0.004 in).
l2nd compression ring = 0.05 to 0.10 mm
(0.002 to 0.004 in).
26.Position oil control expander ring joint and ring
rail gaps all at one side, between gudgeon pin
and away from LH side of piston - viewed from
front of piston. Position the gaps in ring rails
approximately 25 mm (1.0 in) each side of
expander ring joint.
27.Position compression rings with gaps on
opposite side of piston between gudgeon pin
and RH side of piston - viewed from front of
piston.
28.Thoroughly clean cylinder bores.
29.Lubricate piston rings and gudgeon pin with
clean engine oil.
30.Lubricate cylinder bore with clean engine oil.

ENGINE - V8
OVERHAUL 12-2-71
31.Using LRT-12-204, compress piston rings.
32.Insert connecting rod and piston into its
respective cylinder bore, ensuring domed
shaped boss on connecting rod faces towards
front of engine on RH bank of cylinders and
towards rear on LH bank of cylinders.
33.Clean connecting rod journal and bearing cap.
34.Lubricate connecting rod journal and
connecting rod bearings. 35.Fit connecting rod bearings and connecting rod
bearing caps ensuring they are in their correct
fitted order.
NOTE: The rib on the edge of the bearing cap
must face towards the front of the engine on the
RH bank of cylinders and towards the rear on
the LH bank.
36.Fit bolts and tighten to 20 Nm (15 lbf.ft) then
turn a further 80°.
37.Fit oil pick-up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.
38.Fit cylinder head gasket.

+ ENGINE - V8, OVERHAUL, Gasket -
cylinder head.

ENGINE - V8
12-2-72 OVERHAUL
Bearings - connecting rods
$% 12.17.16.01
Disassembly
1.Remove oil pick up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.
2.Suitably mark cylinder reference number on
each connecting rod bearing cap.
3.Remove 2 bolts securing each connecting rod
bearing cap, remove caps and recover
connecting rod bearings.
CAUTION: Keep bearing caps, bearings and
bolts in their fitted order.
4.Push each connecting rod up cylinder bore
until connecting rods are clear of crankshaft
journals.
CAUTION: Ensure that connecting rods do
not contact cylinder bores.
5.Remove bearing shells from each connecting
rod. Inspect
1.Clean crankshaft journals and bearing
locations in connecting rods.
2.Inspect connecting rod bearings for wear and
renew if necessary. Connecting rod bearings
are available in two oversizes.
lConnecting rod bearing 1st oversize = 0.254
mm (0.01 in).
lConnecting rod bearing 2nd oversize =
0.508 mm (0.02 in).
3.Check crankshaft big-end journals for wear and
scoring. Measure for ovality; taking 3
measurements at 120° intervals at each end
and at centre of journals.
lStandard journal = 55.500 to 55.513 mm
(2.20 to 2.22 in).
l1st undersize journal - 0.254 mm (0.01 in) =
55.246 to 55.259 mm (2.17 to 2.18 in).
l2nd undersize journal - 0.508 mm (0.02 in)
= 54.992 to 55.005 mm (2.16 to 2.165 in).
lJournal - max. ovality = 0.040 mm (0.002 in)
Reassembly
1.Clean connecting rod caps.
2.Lubricate connecting rod journals and bearing
shells with clean engine oil.
3.Fit bearing shells to connecting rods and caps.
4.Rotate crankshaft until connecting rod journals
are correctly positioned.
5.Taking care not to displace bearing shells, pull
connecting rods on to crankshaft journals.
6.Check that bearing shells are correctly located
in connecting rod bearing caps.
7.Fit connecting rod bearing caps, ensuring that
they are in their correct fitted order.
NOTE: The rib on the edge of the bearing cap
must face towards the front of engine on the RH
bank of cylinders and towards the rear on the
LH bank.
8.Lightly oil threads of connecting rod bolts. Fit
connecting rod bolts and tighten to 20 Nm (15
lbf.ft) then turn a further 80°.

ENGINE - V8
OVERHAUL 12-2-73
9.Check clearance between connecting rods on
each crankshaft journal.
l Connecting rod clearance = 0.15 to 0.36
mm (0.006 to 0.014 in).
10.Fit oil pick up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.
Crankshaft and main bearings
$% 12.21.33.01
Disassembly
1.Remove crankshaft rear oil seal.

+ ENGINE - V8, OVERHAUL, Seal -
crankshaft - rear - automatic models.
2.Remove timing gear cover gasket.

+ ENGINE - V8, OVERHAUL, Gasket -
timing gear cover.
3.Remove bolt securing camshaft gear.
4.Remove timing chain and gears.
5.Remove connecting rod bearings.

+ ENGINE - V8, OVERHAUL, Bearings
- connecting rods.

ENGINE - V8
12-2-74 OVERHAUL
6.Reference mark main bearing caps to aid
assembly.
7.Remove 10 side bolts securing main bearing
caps to block.
8.Collect 'Dowty' washers from side bolts. Rear
side bolts have Allen heads.
9.Starting at the centre main bearing cap,
progressively loosen, then remove 2 bolts
securing each main bearing cap.
10.Release and remove main bearing caps.
CAUTION: Keep bearing caps, bearings and
bolts in their fitted order.
11.Remove and discard cruciform seals from rear
main bearing cap.
12.Remove crankshaft.
13.Remove main bearings from cylinder block and
main bearing caps.
14.Remove key from keyway.
15.Remove rear main sealing washers.
Inspect
1.Clean crankshaft journals and bearing
locations in cylinder block.
2.Inspect main bearings for wear and renew if
necessary. Main bearings are available in two
oversizes. If 2nd oversize bearing is being
fitted, it may be necessary to grind thrust
face of centre main bearing to achieve
correct end-float.
lMain bearing 1st oversize = 0.254 mm (0.01
in).
lMain bearing 2nd oversize = 0.508 mm
(0.02 in).3.Check main bearing journals for wear and
scoring. Measure for ovality; taking 3
measurements at 120° intervals at each end
and at centre of journals.
lJournal diameter - standard = 63.487 to
63.500 mm (2.499 to 2.520 in).
l1st undersize journal = 63.223 to 63.246
mm (2.511 to 2.512 in).
l2nd undersize journal = 62.979 to 62.992
mm (2.509 to 2.510 in).
lJournal width - standard = 26.975 to 27.026
mm (1.061 to 1.064 in).
lMaximum ovality = 0.040 mm (0.002 in)

ENGINE - V8
OVERHAUL 12-2-75
Reassembly
1.Clean main bearing locations in cylinder block
and bearing caps; ensure bolt holes are clean
and dry.
2.Clean sealant from rear main bearing cap and
mating faces.
3.Fit key to keyway.
4.Check threads of main bearing cap bolts for
damage, renew bolts in pairs.
5.Lubricate grooved main bearing shells with
clean engine oil and fit to their locations in
cylinder block.
NOTE: Ensure that the flanged bearing is fitted
to the centre position.
6.Lubricate crankshaft journals with clean engine
oil.
7.Position crankshaft in cylinder block.
8.Lubricate plain bearing shells with clean
engine oil and fit to main bearing caps.
9.Fit main bearing caps 1 to 4 only at this stage,
ensuring that they are the correct way round
and in their fitted order.
10.Lightly lubricate threads of main bearing cap
bolts with clean engine oil.
11.Fit main bearing cap bolts but do not tighten at
this stage. Do not fit side bolts at this stage.12.Lubricate new cruciform seals with engine oil
and fit to rear main bearing cap.
CAUTION: Do not trim off excess from
cruciform seals at this stage.
13.Apply a 3 mm (0.12 in) wide bead of sealant,
Part No. STC 50550 to bearing cap rear mating
faces on cylinder block.
CAUTION: Ensure sealant does not enter
bolt holes.
14.Carefully fit rear main bearing cap assembly, fit
but do not tighten bolts.
CAUTION: Ensure engine oil does not enter
the side bolt holes in the bearing cap. Do
not trim off excess material from cruciform
seals at this stage.
15.Lubricate 'Dowty' washers with engine oil and
fit to side bolts.
16.Fit but do not tighten side bolts. Rear side
bolts are Allen headed.
17.Using the sequence shown, tighten main
bearing cap bolts as follows:
lInitial torque - all main bearing cap bolts and
side bolts - 13.5 Nm (10 lbf.ft).
lFinal torque - main bearing cap side bolts 11
to 15 - 45 Nm (34 lbf.ft).
lFinal torque - main bearing cap bolts 1 to 8
- 72 Nm (54 lbf.ft).
lFinal torque - main bearing cap bolts 9 and
10 - 92 Nm (68 lbf.ft).
lFinal torque - main bearing cap side bolts 16
to 20 - 45 Nm (34 lbf.ft).
18.Trim off excess material from cruciform seals.