1999 LAND ROVER DISCOVERY coolant

ENGINE - V8
12-2-42 REPAIRS
Refit
1.Clean mating faces of timing gear cover and
cylinder block. Clean dowels and dowel holes.
Ensure bolt holes are clean and dry, remove all
traces of sealant from bolt threads.
2.Fit new gasket, dry, to dowels in cylinder block.
3.Locate tool LRT-12-090 on timing cover and oil
pump drive gear.
4.Position timing cover to cylinder block and at
the same time, rotate tool LRT-12-090 until
drive gear keyway is aligned with Woodruff key.
5.Remove tool LRT-12-090.
6.Apply sealant, Part Number STC 50552 to
threads of timing cover bolts, fit bolts and
working in the sequence illustrated, tighten to
22 Nm (17 lbf.ft) . Ensure CMP sensor multiplug
bracket is secured by bolt.
7. If fitted: Fit new 'O' ring to oil cooler pipe,
connect pipe to timing gear cover and tighten
union to 15 Nm (11 lbf.ft).
8.Connect multiplug to oil pressure switch.
9.Connect multiplug to CMP sensor. 10.Connect coolant hose to coolant pump and
secure with clip.
11.Ensure mating faces of PAS pump pulley and
drive flange are clean, fit pulley and tighten
bolts to 22 Nm (16 lbf.ft).
12.Remove all traces of thread locking material
from coolant pump pulley drive flange bolt
holes using an M8 tap.
13.Ensure mating faces of coolant pump pulley
and drive flange are clean, fit pulley and tighten
new Patchlok bolts to 22 Nm (16 lbf.ft).
14.Ensure mating faces of oil filter and adaptor are
clean, smear clean engine oil onto seal and fit
filter.
15.Fit timing gear cover oil seal.

+ ENGINE - V8, REPAIRS, Seal - cover
- timing gears.
16.Fit oil pick-up strainer.

+ ENGINE - V8, REPAIRS, Strainer -
oil pick-up.
17.Refill cooling system.

+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.

ENGINE - V8
OVERHAUL 12-2-45
OVERHAUL
Gasket - inlet manifold
$% 30.15.08.01
Disassembly
1.Disconnect multiplug from coolant thermistor.
2.Disconnect multiplugs from injectors; release
injector harness from fuel rail and position
aside.
3.Remove 3 bolts securing PAS pump pulley and
remove pulley.
4.Loosen bolt securing jockey pulley and remove
pulley. 5.Remove 4 bolts and one nut securing auxiliary
housing and remove housing.
6.Remove 2 nuts securing alternator cables and
release the cables.
7.Remove two bolts securing alternator and
remove alternator.
8.Remove 4 bolts securing coolant outlet elbow
and remove outlet elbow.
9.Remove and discard 'O' ring.
10.Release ht leads from rocker covers.

ENGINE - V8
OVERHAUL 12-2-47
15.Remove 2 bolts securing manifold gasket and
collect gasket clamps.
16.Remove inlet manifold gasket.
17.Remove gasket seals.
Reassembly
1.Clean sealant from cylinder head and from
notches in the cylinder block.
2.Clean mating faces of cylinder block, cylinder
head and manifold.
CAUTION: Do not use a metal scraper or
machined surfaces may be damaged.
3.Ensure bolt holes are clean and dry.
4.Apply sealant, Part No. STC 50550 to cylinder
head and notches in cylinder block.
5.Fit new gasket seals, ensuring the ends
engage correctly in notches.
6.Apply sealant, Part No. STC 50550 to gasket
seals above the notches in the cylinder block.
7.Fit new manifold gasket, dry.
8.Position gasket clamps, fit and lightly tighten
bolts.
9.Position inlet manifold assembly to cylinder
head. 10.Fit manifold bolts and, working in the sequence
illustrated, tighten as follows:
lInitially, tighten bolts numbered 1, 4, 9 and
12 in numerical order to 5 Nm (4 lbf.ft).
lInlet manifold bolts - initial tighten = 10 Nm
(8 lbf.ft).
lInlet manifold bolts - final tighten = 51 Nm
(38 lbf.ft).
lTighten inlet manifold gasket clamp bolts to
18 Nm (14 lbf.ft).
lTighten inlet manifold bolts to 51 Nm (38
lbf.ft)
11.Clean mating faces of rocker cover and cylinder
head, ensure that bolt holes are clean and dry.
12.Fit new rocker cover gaskets, dry, position
rocker covers, ensuring gaskets are correctly
located.
13.Fit new 'patched' multi-hex rocker cover bolts
ensuring that short bolts are on sides of rocker
coves nearest centre of engine.
14.Tighten bolts by diagonal selection to:
lStage 1 - 3 Nm (2.5 lbf.ft)
lStage 2 - 8 Nm (6 lbf.ft)
15.Ensure that outer rim of each gasket is correctly
positioned around periphery of rocker cover.
16.Secure ht leads to rocker cover.
17.Clean coolant outlet elbow mating faces.
18.Lubricate and fit new 'O' ring to outlet pipe.
19.Position coolant outlet elbow, fit bolts and
tighten to 22 Nm (17 lbf.ft).
20.Position alternator, fit mounting bolts and
tighten to 45 Nm (34 lbf.ft).

ENGINE - V8
12-2-48 OVERHAUL
21.Position alternator cables and tighten terminal
B+ to 18 Nm (13 lbf.ft) and terminal D+ to 5 Nm
(3.5 lbf.ft).
22.Position auxiliary housing, fit bolts and tighten
to 40 Nm (30 lbf.ft). Fit nut and tighten to 22 Nm
(17 lbf.ft).
23.Clean jockey pulley mating faces.
24.Position jockey pulley and tighten bolt to 50 Nm
(37 lbf.ft).
25.Clean PAS pump pulley mating faces.
26.Position PAS pump pulley, fit bolts and tighten
to 22 Nm (17 lbf.ft).
27.Secure injector harness and connect injector
multiplugs.
28.Connect multiplug to coolant thermistor.
Gasket - exhaust manifold
$% 30.15.12.01
Disassembly
1.Remove 8 bolts securing exhaust manifold and
collect spacers. Discard the bolts.
2.Remove exhaust manifold.
3.Remove 2 manifold gaskets and discard.
Reassembly
1.Clean exhaust manifold and cylinder head
mating face.
CAUTION: Do not use a metal scraper or
machined surfaces may be damaged.
2.Fit new gaskets, dry, fit exhaust manifold.
CAUTION: Ensure that link bar on gasket is
positioned below spark plugs.
LH bank illustrated
3.Fit spacers to new manifold bolts and, working
in the sequence illustrated, initially tighten bolts
to 15 Nm (11 lbf.ft), then finally tighten to 38 Nm
(28 lbf.ft).

ENGINE - V8
12-2-56 OVERHAUL
Gasket - timing gear cover
$% 12.65.04.01
Disassembly
1.Remove oil pick up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.
2.Remove and discard 3 bolts securing coolant
pump pulley.
3.Remove coolant pump pulley.
4.Secure tool LRT-12-080 to crankshaft pulley
with 2 bolts.
5.Remove crankshaft pulley bolt.
6.Remove crankshaft pulley. 7.Remove oil filter and discard.
8.Noting the positions of the longer bolts, remove
9 bolts securing timing gear cover.
9.Remove timing gear cover.
10.Remove and discard timing gear cover gasket.
11.Remove seal from timing gear cover and
discard.

ENGINE - V8
OVERHAUL 12-2-57
Reassembly
1.Clean timing gear cover and mating face.
2.Clean oil seal register in timing gear cover.
3.Ensure bolt holes in cylinder block are clean
and dry, remove all traces of sealant from
threads of timing cover bolts.
4.Fit a new timing gear cover gasket, dry, to
timing cover locating dowels.
5.Locate tool LRT-12-090. on timing cover and
oil pump drive gear.
6.Position timing cover to cylinder block and at
the same time rotate tool LRT-12-090. until
drive gear keyway is aligned with Woodruff key.
7.Remove tool LRT-12-090..
8.Apply sealant, Part Number STC 50552 to
threads of timing cover bolts.
9.Align 2 camshaft sensor harness clips to timing
gear cover bolt holes. Noting positions of the
longer bolts and, working in the sequence
shown, tighten timing gear cover bolts to 22
Nm (16 lbf.ft). 10.Apply smear of Retinax LX grease to oil seal
running surface on crankshaft.
CAUTION: Replacement oil seal is pre-
greased, do not apply any additional
lubricant.
11. Fit seal to timing gear cover using tool LRT-12-
089.
12.Clean and fit crankshaft pulley.
13.Fit crankshaft pulley bolt and tighten to 270 Nm
(200 lbf.ft).
14.Remove tool LRT-12-080 from crankshaft
pulley.
15.Clean oil filter mating face.
16.Lubricate new oil filter seal with clean engine oil
and fit filter.
17.Ensure coolant pump and pulley mating faces
are clean.
18.Remove all traces of thread locking material
from coolant pump pulley drive flange bolt
holes using an M8 tap.
19.Fit coolant pump pulley and tighten new
Patchlok bolts to 22 Nm (16 lbf.ft).
20.Fit oil pick up strainer.

+ ENGINE - V8, OVERHAUL, Strainer
- oil pick-up.

EMISSION CONTROL - V8
17-2-26 DESCRIPTION AND OPERATION
Secondary Air Injection System
The secondary air injection (SAI) system comprises the following components:
lSecondary air injection pump
lSAI vacuum solenoid valve
lSAI control valves (2 off, 1 for each bank of cylinders)
lSAI pump relay
lVacuum reservoir
lVacuum harness and pipes
The secondary air injection system is used to limit the emission of carbon monoxide (CO) and hydrocarbons (HCs)
that are prevalent in the exhaust during cold starting of a spark ignition engine. The concentration of hydrocarbons
experienced during cold starting at low temperatures are particularly high until the engine and catalytic converter
reach normal operating temperature. The lower the cold start temperature, the greater the prevalence of
hydrocarbons emitted from the engine.
There are several reasons for the increase of HC emissions at low cold start temperatures, including the tendency for
fuel to be deposited on the cylinder walls, which is then displaced during the piston cycle and expunged during the
exhaust stroke. As the engine warms up through operation, the cylinder walls no longer retain a film of fuel and most
of the hydrocarbons will be burnt off during the combustion process.
The SAI pump is used to provide a supply of air into the exhaust ports in the cylinder head, onto the back of the
exhaust valves, during the cold start period. The hot unburnt fuel particles leaving the combustion chamber mix with
the air injected into the exhaust ports and immediately combust. This subsequent combustion of the unburnt and
partially burnt CO and HC particles help to reduce the emission of these pollutants from the exhaust system. The
additional heat generated in the exhaust manifold also provides rapid heating of the exhaust system catalytic
converters. The additional oxygen which is delivered to the catalytic converters also generate an exothermic reaction
which causes the catalytic converters to 'light off' quickly.
The catalytic converters only start to provide effective treatment of emission pollutants when they reach an operating
temperature of approximately 250°C (482°F) and need to be between temperatures of 400°C (752°F) and 800°C
(1472°F) for optimum efficiency. Consequently, the heat produced by the secondary air injection “afterburning”,
reduces the time delay before the catalysts reach an efficient operating temperature.
The ECM checks the engine coolant temperature when the engine is started in addition to the elapsed time since the
engine was last started. The engine coolant temperature must be below 55°C (131°F) for the SAI pump to run.
NOTE: The ambient air temperature must also be above 8
°C (46°F) for the SAI pump to run.
Also, depending on the long term 'modelled' ambient temperature determined by the ECM, the minimum elapsed time
required since the last engine start can be up to 8.25 hours. The period of time that the SAI pump runs for depends
on the starting temperature of the engine and varies from approximately 96 seconds at 8°C (46°F) to 30 seconds at
55°C (131°F).
Air from the SAI pump is supplied to the SAI control valves via pipework and an intermediate T-piece which splits the
air flow evenly to each bank.
At the same time the secondary air pump is started, the ECM operates a SAI vacuum solenoid valve, which opens to
allow vacuum from the reservoir to be applied to the vacuum operated SAI control valves on each side of the engine.
When the vacuum is applied to the SAI control valves, they open simultaneously to allow the air from the SAI pump
through to the exhaust ports. Secondary air is injected into the inner most exhaust ports on each bank.
When the ECM breaks the ground circuit to de-energise the SAI vacuum solenoid valve, the vacuum supply to the
SAI control valves is cut off and the valves close to prevent further air being injected into the exhaust manifold. At the
same time as the SAI vacuum solenoid valve is closed, the ECM opens the ground circuit to the SAI pump relay, to
stop the SAI pump.
A vacuum reservoir is included in the vacuum line between the intake manifold and the SAI vacuum solenoid valve.
This prevents changes in vacuum pressure from the intake manifold being passed on to cause fluctuations of the
secondary air injection solenoid valve. The vacuum reservoir contains a one way valve and ensures a constant
vacuum is available for the SAI vacuum solenoid valve operation. This is particularly important when the vehicle is at
high altitude.

EMISSION CONTROL - V8
DESCRIPTION AND OPERATION 17-2-27
The ECM connector and pins pertinent for secondary air injection are listed in the following table:
Secondary Air Injection System Components
The secondary air injection (SAI) system components (where fitted) are described below:
Secondary Air Injection (SAI) Pump
1SAI pump cover
2Foam filter3SAI pump
4Pressurised air to exhaust manifolds
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.
Connector / Pin No. Description Signal type Control
C0635-23 Main relay output Output drive Switch to ground
C0636-4 Secondary air injection vacuum solenoid
valve controlOutput, drive Switch to ground
C0636-16 Secondary air injection pump relay control Output drive Switch to ground
C0636-21 Coolant temperature (ECT) sensor Ground 0V
C0636-22 Coolant temperature (ECT) sensor Input signal Analogue 0 - 5V
C0637-20 MIL "ON" Output drive Switch to ground
M17 0204
1
4
2
3