check oil LAND ROVER DISCOVERY 2002 Repair Manual

EMISSION CONTROL - TD5
17-1-4 DESCRIPTION AND OPERATION
Emission Control Systems
Engine design has evolved in order to minimise the emission of harmful by-products. Emission control systems fitted
to Land Rover vehicles are designed to maintain the emission levels within the legal limits pertaining for the specified
market.
Despite the utilisation of specialised emission control equipment, it is still necessary to ensure that the engine is
correctly maintained and is in good mechanical order, so that it operates at its optimum condition.
In addition to emissions improvements through engine design and the application of electronic engine management
systems, special emission control systems are used to limit the pollutant levels developed under certain conditions.
Two main types of additional emission control system are utilised with the Td5 engine to reduce the levels of harmful
emissions released into the atmosphere. These are as follows:
1Crankcase emission control – also known as blow-by gas emissions from the engine crankcase.
2Exhaust gas recirculation – to reduce NO
2 emissions.
Crankcase emission control
All internal combustion engines generate oil vapour and smoke in the crankcase as a result of high crankcase
temperatures and piston ring and valve stem blow-by, a closed crankcase ventilation system is used to vent
crankcase gases back to the air induction system and so reduce the emission of hydrocarbons.
Gases from the crankcase are drawn into the inlet manifold to be burnt in the combustion chambers with the fresh air/
fuel mixture. The system provides effective emission control under all engine operating conditions.
Crankcase gases are drawn through the breather port in the top of the camshaft cover and routed through the breather
hose and breather valve on the flexible air intake duct to be drawn into the turbocharger intake for delivery to the air
inlet manifold via an intercooler.
An oil separator plate is included in the camshaft cover which removes the heavy particles of oil before the crankcase
gas leaves via the camshaft cover port. The rocker cover features circular chambers which promote swirl in the oil
mist emanating from the cylinder head and camshaft carrier. As the mist passes through the series of chambers
between the rocker cover and oil separator plate, oil particles are thrown against the separator walls where they
condense and fall back into the cylinder head via two air inlet holes located at each end of the rocker cover.
The breather valve is a depression limiting valve which progressively closes as engine speed increases, thereby
limiting the depression in the crankcase. The valve is of moulded plastic construction and has a port on the underside
which plugs into a port in the flexible air intake duct. A port on the side of the breather valve connects to the camshaft
cover port by means of a breather hose which is constructed from a heavy-duty braided rubber hose which is held in
place by hose clips. A corrugated plastic sleeve is used to give further protection to the breather hose. The breather
valve is orientation sensitive, and “TOP” is marked on the upper surface to ensure it is mounted correctly.
It is important that the system is airtight so hose connections to ports should be checked and the condition of the
breather hose should be periodically inspected to ensure it is in good condition.

EMISSION CONTROL - V8
DESCRIPTION AND OPERATION 17-2-9
Emission Control Systems
Engine design has evolved in order to minimise the emission of harmful by-products. Emission control systems are
fitted to Land Rover vehicles which are designed to maintain the emission levels within the legal limits pertaining for
the specified market.
Despite the utilisation of specialised emission control equipment, it is still necessary to ensure that the engine is
correctly maintained and is in good mechanical order so that it operates at its optimal condition. In particular, ignition
timing has an effect on the production of HC and NO
x emissions, with the harmful emissions rising as the ignition
timing is advanced.
CAUTION: In many countries it is against the law for a vehicle owner or an unauthorised dealer to modify or
tamper with emission control equipment. In some cases, the vehicle owner and/or the dealer may even be
liable for prosecution.
The engine management ECM is fundamental for controlling the emission control systems. In addition to controlling
normal operation, the system complies with On Board Diagnostic (OBD) system strategies. The system monitors and
reports on faults detected with ignition, fuelling and exhaust systems which cause an excessive increase in tailpipe
emissions. This includes component failures, engine misfire, catalyst damage, catalyst efficiency, fuel evaporative
loss and exhaust leaks.
When an emission relevant fault is determined, the fault condition is stored in the ECM memory. For NAS vehicles,
the MIL warning light on the instrument pack will be illuminated when the fault is confirmed. Confirmation of a fault
condition occurs if the fault is still found to be present during the driving cycle subsequent to the one when the fault
was first detected.

+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine
management.
The following types of supplementary control system are used to reduce harmful emissions released into the
atmosphere from the vehicle:
1Crankcase emission control – also known as blow-by gas emissions from the engine crankcase.
2Exhaust emission control – to limit the undesirable by-products of combustion.
3Fuel vapour evaporative loss control – to restrict the emission of fuel through evaporation from the fuel
system.
4Fuel leak detection system (NAS only) – there are two types of system which may be used to check the
evaporative emission system for the presence of leaks from the fuel tank to purge valve.
aVacuum leak detection test – checks for leaks down to 1 mm (0.04 in.) in diameter.
bPositive pressure leak detection test – utilises a leak detection pump to check for leaks down to 0.5 mm (0.02
in.) in diameter.
5Secondary air injection system (NAS only) – to reduce emissions experienced during cold starting.
Crankcase emission control system
The concentration of hydrocarbons in the crankcase of an engine is much greater than that in the vehicle's exhaust
system. In order to prevent the emission of these hydrocarbons into the atmosphere, crankcase emission control
systems are employed and are a standard legal requirement.
The crankcase ventilation system is an integral part of the air supply to the engine combustion chambers and it is
often overlooked when diagnosing problems associated with engine performance. A blocked ventilation pipe or filter
or excessive air leak into the inlet system through a damaged pipe or a leaking gasket can affect the air:fuel mixture,
performance and efficiency of the engine. Periodically check the ventilation hoses are not cracked and that they are
securely fitted to form airtight connections at their relevant ports.
The purpose of the crankcase ventilation system is to ensure that any noxious gas generated in the engine crankcase
is rendered harmless by complete burning of the fuel in the combustion chamber. Burning the crankcase vapours in
a controlled manner decreases the HC pollutants that could be emitted and helps to prevent the development of
sludge in the engine oil as well as increasing fuel economy.

EMISSION CONTROL - V8
17-2-42 DESCRIPTION AND OPERATION
Secondary air injection system
When the engine is started, the engine control module checks the engine coolant temperature and if it is below 55°
C, the ECM grounds the electrical connection to the coil of the secondary air injection (SAI) pump relay.
A 12V battery supply is fed to the inertia switch via fuse 13 in the engine compartment fusebox. When the inertia
switch contacts are closed, the feed passes through the switch and is connected to the coil of the Main relay. An earth
connection from the Main relay coil is connected to the ECM. When the ECM completes the earth path, the coil
energises and closes the contacts of the Main relay.
The Main and Secondary Air Injection (SAI) pump relays are located in the engine compartment fusebox. When the
contacts of the Main relay are closed, a 12V battery supply is fed to the coil of the SAI pump relay. An earth connection
from the coil of the SAI pump relay is connected to the ECM. When the ECM completes the earth path, the coil
energises and closes the contacts of the SAI pump relay to supply 12V to the SAI pump via fusible link 2 in the engine
compartment fusebox. The SAI pump starts to operate, and will continue to do so until the ECM switches off the earth
connection to the coil of the SAI pump relay.
The SAI pump remains operational for a period determined by the ECM and depends on the starting temperature of
the engine, or for a maximum operation period determined by the ECM if the target engine coolant temperature has
not been reached in the usual time.
When the contacts of the main relay are closed, a 12V battery supply is fed to the SAI solenoid valve via Fuse 2 in
the engine compartment fusebox.
The ECM grounds the electrical connection to the SAI vacuum solenoid valve at the same time as it switches on the
SAI pump motor. When the SAI vacuum solenoid valve is energised, a vacuum is provided to the operation control
ports on both of the vacuum operated SAI control valves at the exhaust manifolds. The control vacuum is sourced
from the intake manifold depression and routed to the SAI control valves via a vacuum reservoir and the SAI vacuum
solenoid valve.
The vacuum reservoir is included in the vacuum supply circuit to prevent vacuum fluctuations caused by changes in
the intake manifold depression affecting the operation of the SAI control valves.
When a vacuum is applied to the control ports of the SAI control valves, the valves open to allow pressurised air from
the SAI pump to pass through to the exhaust ports in the cylinder heads for combustion.
When the ECM has determined that the SAI pump has operated for the desired duration, it switches off the earth paths
to the SAI pump relay and the SAI vacuum solenoid valve. With the SAI vacuum solenoid valve de-energised, the
valve closes, cutting off the vacuum supply to the SAI control valves. The SAI control valves close immediately and
completely to prevent any further pressurised air from the SAI pump entering the exhaust manifolds.
The engine coolant temperature sensor incurs a time lag in respect of detecting a change in temperature and the SAI
pump automatically enters a 'soak period' between operations to prevent the SAI pump overheating. The ECM also
compares the switch off and start up temperatures, to determine whether it is necessary to operate the SAI pump.
This prevents the pump running repeatedly and overheating on repeat starts.
Other factors which may prevent or stop SAI pump operation include the prevailing engine speed / load conditions.

ENGINE MANAGEMENT SYSTEM - V8
DESCRIPTION AND OPERATION 18-2-33
In the event of an IACV signal failure any of the following symptoms may be observed:
lEither low or high idle speed.
lEngine stalls.
lDifficult starting.
lIdle speed in default condition.
There are eight IACV diagnostic checks performed by the ECM:
lOutput short circuit to earth – opening coil
lOutput short circuit to battery supply – opening coil
lOutput open circuit – opening coil
lOutput short circuit to earth – closing coil
lOutput short circuit to battery voltage – closing coil
lOutput open circuit – closing coil
lBlocked IACV – rev/min error low (engine speed must be 100 rev/min less than the target speed, engine load
less than 2.5 and the measured air flow more than 10 kg/h less than the expected air flow for a fault condition to
be flagged).
lBlocked IACV – rev/min error high (the engine speed must be more than 180 rev/min greater than the target
speed and the measured air flow more than 10 kg/h greater than the expected air flow for a fault condition to be
flagged).
Should a malfunction of the component occur, the following fault codes may be evident and can be retrieved by
TestBook.
Fuel pump relay
The fuel pump relay is located in the engine compartment fuse box. It is a 4 pin normally open relay. Input from the
ECM allows the fuel pump relay to control the electrical input to the fuel pump, regulating the fuel supply to the fuel
injectors. When the ignition is switched on and the engine is cranked, the fuel pump relay is activated by the ECM,
allowing the fuel system to be pressurised to 3.5 bar (52 lbf.in
2). The ECM then deactivates the relay until the engine
has started.
If the fuel pump runs, but the fuel pressure is out of limits, adaptive fuel faults will be stored.
P Code J2012 Description Land Rover Description
P1510 IACV opening coil malfunction Short circuit to battery supply - opening winding
P1513 IACV opening coil malfunction Short circuit to earth - opening winding
P1514 IACV opening coil malfunction Open circuit - opening winding
P1553 IACV closing coil malfunction Short circuit to battery supply - closing winding
P1552 IACV closing coil malfunction Short circuit to earth - closing winding
P1551 IACV closing coil malfunction Open circuit - closing winding
P0505 Idle control system malfunction Blocked IACV - high or low rev/min error

MANIFOLDS AND EXHAUST SYSTEMS - V8
REPAIRS 30-2-15
Refit
1.Clean old RTV sealant from cylinder head and
cylinder block notches.
2.Clean mating faces of cylinder block, cylinder
head and inlet manifold.
3.Apply RTV sealant to cylinder head and
cylinder block notches.
4.Fit new gasket seals, ensuring ends engage
correctly in notches.
5.Fit new inlet manifold gasket.
6.Position gasket clamps and fit bolts, but do not
tighten at this stage.
7.Position inlet manifold to engine. Fit manifold
bolts and, working in the sequence shown,
tighten bolts initially to 10 Nm (7 lbf.ft) then to
51 Nm (38 lbf.ft).
8.Tighten gasket clamp bolts to 18 Nm (13 lbf.ft).
9.Connect fuel pipe.
10.Clean top hose outlet pipe mating faces.
11.Fit new 'O' ring to outlet pipe.
12.Position outlet pipe, fit bolts and tighten to 22
Nm (16 lbf.ft).
13.Position alternator, fit bolts and tighten to 45
Nm (33 lbf.ft).
14.Position PAS pump to auxiliary housing and
locate housing on engine. Fit bolts and tighten
to 40 Nm (30 lbf.ft).
15.Fit and tighten auxiliary housing nut to 10 Nm (7
lbf.ft).
16.Fit bolts securing PAS pump and tighten to 22
Nm (16 lbf.ft). 17.Position oil cooling pipe bracket fit bolt and
tighten to 22 Nm (16 lbf.ft).
18.Fit and tighten PAS pump high pressure pipe.
19.Position jockey pulley and tighten bolt to 50 Nm
(37 lbf.ft).
20.Clean PAS pump pulley mating faces.
21.Position PAS pump pulley, fit bolts and tighten
to 22 Nm (16 lbf.ft).
22.Clean ACE pump dowels and dowel holes.
23.Position ACE pump, fit bolts and tighten to 22
Nm (16 lbf.ft).
24.Fit auxiliary drive belt.

+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
25.Secure injector harness and connect injector
multiplugs.
26.Position top hose and secure clips.
27.Fit rocker covers.
l

+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - LH.
l

+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - RH.
28.Check and top up PAS fluid

MANUAL GEARBOX - R380
OVERHAUL 37-29
20.Check end float of 3rd gear between gear and
flange on output shaft:
lNew = 0.11 - 0.21 mm (0.004 - 0.0083 in)
lService limit = 0.337 mm (0.013 in)
21.Check output shaft and layshaft end float as
follows.
22.The end float setting for both shafts is:
lNew = 0.00 to 0.05 mm (0.0 to - 0.002 in)
lService limit = 0.05 mm (0.002 in)
23.Fit front cover to gearbox case without the oil
seal and tighten bolts by diagonal selection to
25 Nm (18 lbf.ft).
24.Position in vice with front cover facing
downwards.
25.Fit input shaft to gearbox case less 4th gear
baulk ring.
26.Fit output shaft assembly to input shaft.
27.Fit output shaft bearing track and shim to centre
plate.
28.Fit centre plate to gearbox case and secure
using 8 slave bolts.
29.Rotate output shaft to settle bearings.
30.Fit a suitably large ball bearing into end of
output shaft.
31.Position a suitable DTI and zero probe on ball
bearing.
32.Lift output shaft and note DTI reading.
33.If reading is incorrect, dismantle and fit shim to
give correct end float.
34.Repeat above procedure.
35.Repeat procedure for layshaft end float.
36.Remove and discard 6 bolts and remove
gearbox front cover.
37.Fit gearbox selector fork - set.

+ MANUAL GEARBOX - R380,
OVERHAUL, Fork - set - selector shaft.
38.Fit gearbox front cover.

+ MANUAL GEARBOX - R380,
OVERHAUL, Cover - front.
Synchroniser - gearbox - set
$% 37.20.07
Disassembly
1.Remove gearbox selector fork set.

+ MANUAL GEARBOX - R380,
OVERHAUL, Fork - set - selector shaft.
2.Using tool LRT-99-002 and support bars
under 1st gear, press output shaft bearing from
output shaft.
3.Remove 1st gear, bearing collar, needle roller
bearing and synchromesh rings.
4.Noting its fitted position, remove 1st / 2nd gear
synchroniser hub, 2nd gear synchromesh
rings, 2nd gear and needle roller bearing.

MANUAL GEARBOX - R380
OVERHAUL 37-45
5.Remove 2 bolts securing spool retainer to
gearbox case. Remove retainer, remove and
discard 'O' ring - if fitted.
6.Remove interlock spool from selector shaft.
7.Remove filter from gearbox case.
8.Align selector shaft pin with slot in centre plate
and using wooden blocks and hide mallet,
release centre plate and collect lower detent
ball and spring. 9.Press out reverse idler shaft using a suitable
press.
10.Remove idler gear, needle roller bearing and
spacer.
Reassembly
1.Clean centre plate and reverse gear
components.
2.Lubricate gearbox components with clean gear
oil.
3.Position idler gear, bearing and spacer to idler
shaft.
4.Using a suitable press fit idler shaft to centre
plate.
5.Using feeler gauges, check clearance between
reverse idler and shaft flange; fit a thicker or
thinner spacer if necessary in order to achieve
correct clearance:
lNew clearance = 0.04 - 0.38 mm (0.002 -
0.015 in)
lService limit = 0.38 mm (0.015 in)
6.Apply sealant, Part No. STC 3254 to gearbox
casing.
7.Fit lower spring and detent ball into centre
plate, retain using a dummy shaft.
8.Align selector shaft pin with slot in centre plate.
9.Fit centre plate and fit 2 off 8x35 mm slave bolts
to retain centre plate in position on gearbox
case; recover dummy shaft.

TRANSFER BOX - LT230SE
REPAIRS 41-35
3.Fit new seal using tool LRT-41-012.
4.Position drive flange, fit new felt and steel
washers.
5.Position tool LRT-51-003 and tighten new
drive flange nut to 148 Nm (109 lbf.ft).
6.Position handbrake drum and tighten screw.
7.Tighten brake shoe adjuster bolt to 25 Nm (18
lbf.ft) then loosen one and a half turns.
8.Check that brake drum is free to rotate.
9.Fit propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
10.Top-up transfer box oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
Gasket - rear output shaft housing
$% 41.20.55
Remove
1.Drain transfer gearbox oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
2.Remove rear output shaft seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Seal - rear output shaft.
3.Mark output shaft housing to main casing for
assembly purposes.
4.Note position of shoulder bolt, remove 6 bolts
securing housing to main casing.
Refit
1.Clean output shaft housing, mating face on
main casing and sealant from bolt threads.
2.Apply sealant, Part No. STC 3254 to mating
flange on output shaft housing.
3.Fit output shaft housing to main casing.
4.Apply Loctite 290 to bolt threads.
5.Fit output shaft housing bolts and tighten by
diagonal selection to 45 Nm (33 lbf.ft).
6.Fit rear output shaft seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Seal - rear output shaft.
7.Fill transfer gearbox with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.

TRANSFER BOX - LT230SE
OVERHAUL 41-49
19.Check width of high/low selector groove.
lGroove width = 16.0 to 16.1 mm (0.63 to
0.64 in).
20.Check high/low selector fork for cracks and
wear. Check selector fork finger width.
lFinger width = 7.37 to 7.47 mm (0.290 to
0.294 in).
21.03 MY onwards: Check high/low selector fork
clips for wear and damage. Check spring for
distortion, check free length of spring:
lSpring free length = 75 mm (2.95 in)
Note: High/low selector shaft, fork and spring
fitted to 03 MY transfer boxes may be fitted to
pre 03 MY boxes as an assembly.
22.Check differential sun and planet gears for
wear, cracks and chipping of teeth.
23.Check cross shafts and recesses in both halves
of differential carrier for damage and
wear.Ensure planet gears are retained with
their respective shafts.
24.Check retaining ring for distortion.
25.Check differential splines for wear and
damage.26.Check high/low hub for cracks, chipping and
uneven wear. Check width of selector fork
groove.
lGroove width = 7.5 to 7.6 mm (0.295 to 0.30
in).
27.Check splines and teeth on high/low selector
sleeve for uneven wear, cracks, damage and
chipping.
28.Check teeth of high and low range gears for
cracks, chipping and uneven wear.
29.Check high range gear bush for wear and
damage.
Reassembly
1.Lubricate all components with recommended
oil and lightly oil the differential bolt threads.

TRANSFER BOX - LT230SE
OVERHAUL 41-55
37.Heat the front output housing to 100°C (210°F)
and fit new output shaft bearing using tool
LRT-41-011.
38.Allow housing to air cool.
39.Fit new bearing retaining circlip ensuring that
circlip is fully seated.
40.Using tool LRT-41-012, fit new output shaft oil
seal. Check that oil seal is just contacting
circlip. 41.Position selected shim in front output housing
and using tool LRT-54-003, fit new differential
front bearing track.
42.Fit bearing spacer to output shaft with chamfer
on spacer towards threaded end.
43. If fitted: Fit dog clutch with flange on clutch
facing towards splined end.
44.Using a copper mallet, drive output shaft into
bearing.
Note: Carry out the following operations for
transfer boxes fitted with differential lock.
45.Compress differential lock selector spring and
fit selector fork.
46.Position selector fork to groove in dog clutch.
47.Fit selector shaft and locate in housing recess,
rotate shaft until the two flats for retaining clips
are at right angles to the cover plate mating
face.