1999 LAND ROVER DISCOVERY length

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.

EMISSION CONTROL - V8
17-2-28 DESCRIPTION AND OPERATION
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 (SAI) pump is found to be malfunctioning, the following fault codes may be stored in the
ECM diagnostic memory, which can be retrieved using Testbook/T4:
NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to
determine root cause of fault codes.
NOTE: The electrical test of the SAI pump powerstage only indicates that there is a problem with the relay or the
power supply to the relay. It does not indicate the state of the SAI pump itself (i.e. broken or not connected).
As a result of a SAI pump powerstage malfunction, other fault codes may also become stored in the ECM memory.
These may include the following P codes.
NOTE: A malfunction of the SAI pump powerstage is logically expected to result in both engine banks reporting the
same fault.
NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to
determine root cause of fault codes.
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 System – Relay 'A' circuit malfunction (SAI pump
powerstage fault, e.g. - SAI pump relay fault or relay not connected / open circuit /
harness damage).
P-code Description
P1412Secondary Air Injection System – Malfunction Bank 1 LH (Insufficient SAI flow
during passive test)
P1414Secondary Air Injection System – Low air flow Bank 1 LH (Insufficient SAI flow
during active test)
P1415Secondary Air Injection System – Malfunction Bank 2 RH (Insufficient SAI flow
during passive test)
P1417Secondary Air Injection System – Low air flow Bank 2 RH (Insufficient SAI flow
during active test)

ENGINE MANAGEMENT SYSTEM - V8
DESCRIPTION AND OPERATION 18-2-53
Function
With the ECM operating in the 'New' state, TestBook is required to instruct the ECM to learn the new BCU code. If the
ECM is in delivery state (i.e. direct from the supplier), it will not run the vehicle and will store a new ECM fault code
when it is fitted. This code must be cleared after instructing the ECM to learn the BCU code using TestBook.
When the ECM is in the 'Secure' state, no further action is required as the ECM has successfully learned the BCU
code. A 'Secure' ECM can not be configured to a 'No Code' state.
If the vehicle is fitted with an ECM with a valid code, the engine will start and the MIL will go out.
However, if the ECM has an invalid BCU security code the engine will crank, start, and then immediately stall. The
status of the security system can only be interrogated using TestBook.
TestBook is able to retrieve the following immobilisation fault codes:
Misfire detection
Due to increasing legislation, all new vehicles must be able to detect two specific levels of misfire.
Conditions
The ECM is able to carry out misfire detection as part of the OBD system using the following component parts:
lFlywheel reluctor adaptation.
lCalculation of engine roughness.
lDetection of excess emissions misfire.
lDetection of catalyst damaging misfire.
Function
The flywheel/ reluctor ring is divided into four segments 90° wide. The ECM misfire detection system uses information
generated by the CKP to determine crankshaft speed and position. If a misfire occurs, there will be an instantaneous
slight decrease in engine speed. The ECM misfire detection system is able to compare the length of time each 90°
segment takes and is therefore able to pinpoint the source of the misfire.
For the ECM misfire detection system to be calibrated for the tolerances of the reluctor tooth positions, the flywheel/
reluctor ring must be 'adapted' as follows:
l1800 - 3000 rev/min = speed range 1.
l3000 - 3800 rev/min = speed range 2.
l3800 - 4600 rev/min = speed range 3.
l4600 - 5400 rev/min = speed range 4.
The ECM carries out flywheel/ reluctor ring adaptions across all the above speed ranges and can be monitored by
TestBook. The test should be carried out as follows:
lEngine at normal operating temperature.
lSelect second gear (for both automatic and manual transmission vehicles).
lAccelerate until engine rev limiter is operational.
lRelease throttle smoothly to allow engine to decelerate throughout the speed ranges.
lRepeat process as necessary until all adaptations are complete.
P Code J2012 Description Land Rover Description
P1666 Engine anti-theft signal circuit malfunction BCU serial link frame/ bit timing error
P1667 Engine anti-theft signal circuit low Serial link short circuit to earth
P1668 Engine anti-theft signal circuit high Serial link open circuit
P1672 Engine anti-theft signal circuit wrong code
receivedSecure ECM, received incorrect code
P1673 Engine anti-theft signal new engine control
module not configuredNew ECM fitted
P1674 Engine anti-theft signal No code ECM, valid code received

TRANSFER BOX - LT230SE
OVERHAUL 41-45
4. 03 Model Year onwards: Using tools LRT-99-
003 and LRT-41-006, fit bearing tracks to
intermediate gears ensuring that tracks are fully
seated against shoulders in gears.
5.Using a micrometer, measure the width of each
bearing inner track. 6.Record each reading as measurement 'A' and
'B', both measurements should fall within the
range of 21.95 to 22.00 mm (0.864 to 0.866 in).
7.Fit inner bearing track 'A' onto tool LRT-41-017
and position intermediate gear cluster onto
bearing 'A'.
8.Fit inner bearing track 'B' to intermediate gear,
apply finger pressure to bearing inner track
and rotate intermediate gear 5 to 10 turns to
settle in bearing rollers.
9.Attach a DTI to base of tool LRT-41-017 , zero
gauge on top of tool post and take 2
measurements at 180° of the step height
between the top of the tool post and the
bearing inner track. Take an average of the two
readings and record this as measurement 'C'.
Measurement 'C' should be in the range of 0.15
to 0.64 mm (0.006 to 0.025 in).
10.Using the formula 103.554 mm (4.0769 in) -'A'-
'B'-'C', calculate the length of bearing spacer
required. From the result of the calculation
round DOWN to the nearest length of spacer
available to give a correct bearing pre-load of
0.005 mm (0.002 in). 40 spacers are
available ranging in length from 58.325 mm
(2.296 in) to 59.300 mm (2.335 in) rising in
increments of 0.025 mm (0.001 in).
11.Remove intermediate gear assembly from tool
LRT-41-017.
12.Lubricate and fit bearings and selected spacer
to intermediate gear.
13.Position tool LRT-41-004 through bearings
and spacer.

TRANSFER BOX - LT230SE
OVERHAUL 41-53
11.Check differential lock selector fork for cracks
and wear.
12.Check selector fork finger width.
lFinger width = 7.92 to 7.97 mm (0.311 to
0.313 in).
13.Check differential lock selector fork clips for
wear and damage. Check spring for distortion
and free length.
lSpring free length = 84.58 mm (3.33 in).
14.Check dog clutch internal teeth and grooves
and teeth on output shaft for wear and
damage. Check selector fork groove width.
lGroove width = 8.05 to 8.20 mm (0.32 to
0.33 in).
15.Carry out the following inspection procedures
for all transfer boxes.
16.Check threads and splines of output shaft for
damage and wear. Check dog clutch teeth on
shaft for wear and damage.17. 03 Model Year onwards: Compress high/low
selector fork spring and remove retaining clips
from each end of spring, remove high/low
selector shaft.
High/low selector shaft fitted to pre 03 Model Year
illustrated.
18.Check detent grooves in high/low selector shaft
for wear. Do not remove fork from shaft
unless either component is being renewed.
If fork is removed from shaft, coat the
threads of the set screw with sealant, Part
No. STC 50552 prior to assembling.
19.Check width of high/low selector groove.
lGroove width = 16.0 to 16.1 mm (0.63 to
0.64 in).

TRANSFER BOX - LT230SE
41-54 OVERHAUL
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 Model Year 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 Model Year transfer boxes may be
fitted to pre 03 Model Year 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.

TRANSFER BOX - LT230SE
OVERHAUL 41-55
Reassembly
1.Lubricate all components with recommended
oil and lightly oil the differential bolt threads.
2.Secure rear half of differential carrier in a soft
jawed vice.
3.Fit each planet gear to its respective cross
shaft, fit new dished thrust washer to each
gear.
4.Fit cross shafts, planet gears and dished thrust
washers in rear half of carrier.Ensure that
cross shafts are fitted correctly. Do not fit
the sun gear into the rear half carrier at this
stage.
5.Fit retaining ring.
6.Fit a 1.05 mm (0.04 in) thrust washer to sun
gear from front half of carrier. Position gear in
front half of carrier.
7.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
8.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).9.Insert the front output shaft into the front half of
the carrier and check that the gears rotate
freely.
10.Fit output flange on to the splines of the output
shaft, but do not fit flange nut at this stage.
11.Fit transmission brake drum to output flange
and secure the drum using 2 nuts.
12.Secure a length of cord around the drum and
attach one end of the cord to a spring balance.
13.Pull on the spring balance and note the load at
which the brake drum starts to turn. Used
gears should rotate smoothly, while new
gears will have a 'notchy' feel as they rotate.
14.Compare the figure obtained with the following.
lUsed gears = 0.45 kg (1.0 lb)
lNew gears = 1.72 kg (3.8 lb)
15.If the load to turn figure is below the specified
limits, proceed as follows.
16.Remove the front output shaft and brake drum.
17.Remove the 8 bolts securing the two halves of
the differential carrier
18.Separate the differential carrier and remove the
sun gear and thrust washer from the front half.
19.Select a thicker thrust washer from the range
available. 5 different thrust washers are
available, rising in increments of 0.10 mm
(0.004 in) from 1.05 mm to 1.45 mm (0.04 to
0.06 in).
20.Repeat steps 7 to 19 as necessary until the
load to turn figure is as specified
21.When specified load to turn is obtained,
proceed as follows.
22.Remove the front output shaft and brake drum.
23.Remove the 8 bolts securing the two halves of
the differential carrier
24.Separate the differential carrier and remove the
sun gear and thrust washer from the front
half.Retain the selected thrust washer with
its sun gear.

PROPELLER SHAFTS
47-2 DESCRIPTION AND OPERATION
Description
General
Front and rear propeller shafts transmit the drive from the transfer box to the axles.
On vehicles from 03 model year fitted with the 4.6l V8 engine and 4HP24 transmission, the front propeller shaft is 15
mm (0.6 in) longer and the rear propeller shaft is 15mm (0.6 in) shorter than those used on vehicles with the 4.0l V8
and Td5 engines. This is to accomodate an increase in length of the 4HP24 transmission.