engine LAND ROVER DISCOVERY 1999 Workshop Manual
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 1999, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 1999Pages: 1529, PDF Size: 34.8 MB
Page 464 of 1529
CLUTCH - V8
DESCRIPTION AND OPERATION 33-2-9
Operation
Hydraulic operation
Refer to illustration.
+ CLUTCH - V8, DESCRIPTION AND OPERATION, Hydraulic operation.
When the clutch pedal is depressed, the master cylinder piston is pushed into the master cylinder. The movement of
the piston pressurises the fluid in the master cylinder, forcing the pressurised fluid into the hydraulic feed pipe to the
slave cylinder. The hydraulic pressure is felt at the slave cylinder piston which moves under the hydraulic force
applied, pushing the clutch release lever via the piston rod.
When the clutch pedal is released, the force applied to the release lever by the fingers of the diaphragm, moves the
release lever, which pushes the slave cylinder piston into the cylinder. The displaced hydraulic fluid is pushed up the
hydraulic feed pipe and returned to the master cylinder.
Mechanism operation
When the clutch pedal is depressed, hydraulic pressure extends the piston and rod in the slave cylinder. The
extension of the piston pushes the rod against the outer end of the release lever which pivots around the ball spigot.
The inner end of the release lever pivots towards the engine applying pressure to the release bearing. The release
bearing slides along the release bearing sleeve and pushes on the fingers of the diaphragm. The diaphragm pivots
about the fulcrum rings in the cover. As the diaphragm is deflected, it removes pressure from the pressure plate. The
pressure plate moves away from the drive plate assisted by the three leaf springs and retractor clips.
The removal of force from the pressure plate on the drive plate reduces the friction between the flywheel, drive plate
and pressure plate. The drive plate slips between the flywheel and the pressure plate preventing rotary movement
being transferred from the flywheel and pressure plate to the primary driveshaft.
When the clutch pedal is released, hydraulic force is removed from the piston in the slave cylinder. This allows the
fingers of the diaphragm to push the release bearing along the release bearing sleeve. The movement of the release
bearing moves the release lever which pivots on the ball spigot, pushing the piston and rod back into the slave
cylinder.
The removal of pressure from the release bearing on the diaphragm, causes the diaphragm to pivot around the
fulcrum rings in the cover. The force applied to the pressure plate from the diaphragm overcomes the force of the leaf
springs and the pressure plate moves towards the drive plate and flywheel.
The pressure plate applies pressure to the drive plate which is pushed against the flywheel. As the clutch pedal is
progressively released, the friction between the drive plate, flywheel and pressure plate increases. The increase in
friction transfers the rotary movement of the flywheel and pressure plate to the drive plate which in turn starts to rotate
the primary driveshaft. When the clutch pedal is released fully, the force applied by the diaphragm to the pressure
plate forces the drive plate onto the flywheel with no slippage.
Page 478 of 1529
MANUAL GEARBOX - R380
DESCRIPTION AND OPERATION 37-7
Description
General
The R380 all synchromesh gearbox has five forward speeds and reverse and is mounted in line with the engine. The
clutch bell housing is bolted to the front of the gearbox and the transfer box is mounted at the rear.
Gearbox casings
Gearbox casings consist of a front cover, gearcase, centre plate and extension housing. All casings with the exception
of the front cover are located to each other by dowels and sealed. Gearbox filler/level and drain plugs are located in
the gearcase.
Reverse lamp switch
A reverse lamp switch is inserted into the extension housing. Selection of reverse gear will close the switch allowing
current from fuse 25 to flow through the switch to illuminate the reverse lamps. The switch also provides a feed to the
BCU and the electrochromic automatic interior mirror - if fitted; the mirror moving from the dimmed position if
applicable.
Gearchange assembly
The gearchange assembly is bolted to the top of the gearcase, the upper gear lever being attached to the lower gear
lever by means of a clamp bolt. The lower gear lever ball is housed in a Railko bush inserted in the gear change
housing, the end of the lever locating in the selector yoke which is attached to the end of the selector shaft. Bias
springs provide a positive return of the gear lever to the neutral position with selection of 1st/2nd and 5th/reverse gears
being against bias spring pressure. Spring loaded detent balls fitted in the centre plate locate in grooves in the selector
shaft to provide positive gear and neutral selection.
Lubrication
Lubrication is by an oil pump located in the extension housing and driven by the layshaft with additional lubrication
being provided by splash. The pump directs oil via a filter and internal drillings in the output shaft to lubricate the
components. On non UK and non European models, provision for oil cooling is by means of a thermostat housed in
a cover bolted to the side of the extension housing. The cover incorporates tappings for connections to an oil cooler.
On UK and European models, the thermostat and cover are replaced by an oil by-pass block.
Internal pressures produced within the gearbox are vented to atmosphere via a plastic breather pipe. The pipe is
attached to the extension housing and is routed across the top of the gearcase and secured at the open end by a clip
attached to the engine cylinder block.
Selector shaft and forks
Selector forks for 1st/2nd, 3rd/4th and 5th/reverse gears are located on a single selector shaft; the 1st/2nd and 3rd/
4th selector forks are inside the main gearcase whilst the 5th/reverse selector fork is inside the extension housing.
Each of the selector forks locates inside its corresponding synchromesh hub.
Synchromesh assemblies
Each synchromesh assembly is located on the output shaft adjacent to its corresponding gears and comprises a
synchromesh ring, hub, slippers and sleeve. The hubs and slippers are retained in the sleeves by means of spring
clips. 1st/2nd and 3rd synchromesh assemblies are fitted with double synchromesh rings whilst 4th, 5th and reverse
assemblies are fitted with single rings.
The gear train
The gear train comprises an input shaft, output shaft, layshaft and reverse idler shaft together with their appropriate
gears and synchromesh assemblies.
The gear train input shaft, output shaft and layshaft are supported by taper roller bearings with all gears on the input
and output shafts running on caged needle roller bearings. Layshaft gears are integral with the shaft with the
exception of reverse/5th gears which are splined to the shaft and retained with a nut. 1st, 2nd, 3rd and 4th gears are
shot peened to improve durability. The reverse idler shaft and gear are supported in the centre plate by a caged
needle roller bearing. End-float of the output shaft and layshaft is controlled by selective shims located in the centre
plate whilst reverse idler shaft end-float is controlled by a selective shim located behind reverse gear.
Page 486 of 1529
MANUAL GEARBOX - R380
REPAIRS 37-15
32.Remove 3 bolts securing oil cooling pipe
housing to gearbox, release housing and
discard 'O' rings.
33.Using a second jack support the weight of the
engine.
34.Remove 14 bolts securing gearbox to engine.
35.With assistance, remove gearbox from engine.
Refit
1.Clean gearbox to engine mating faces, dowels
and dowel holes.
2.Raise gear gearbox on jack and align to clutch
and engine.
3.Fit bolts securing gearbox to engine and
tighten to 45 Nm (33 lbf.ft).
4.Lubricate and fit new 'O' rings to oil cooling
pipe housing. 5.Position coolant pipe housing, fit bolts and
tighten to 25 Nm (18 lbf.ft).
6. If fitted: Secure harness in retaining clips,
connect Lucars to differential lock warning
switch and multiplug to neutral sensor.
7.Position breather pipes and secure 'P' clip with
bolt.
8.Using new sealing washers fit breather pipe
banjo bolts and tighten to 15 Nm (11 lbf.ft).
9.Connect oil temperature sensor Lucars and
reverse lamp switch multiplug.
10.Position low ratio selector cable to housing and
secure with 'C' washer and clevis pin.
11.Secure cable to fuel pipes with new cable ties.
12.Raise gearbox, ensuring gear change lever is
located in grommet.
13.Fit gearbox mountings and tighten bolts to 85
Nm (63 lbf.ft).
14.Fit nuts to mountings and tighten to 48 Nm (37
lbf.ft).
15.Remove 3 bolts securing support plate to
gearbox.
16.Position clutch slave cylinder and heat shield,
fit bolts and tighten to 25 Nm (18 lbf.ft).
17.Clean handbrake back plate and mating face.
18.Position handbrake back plate, fit bolts and
tighten to 75 Nm (46 lbf.ft).
19.Clean handbrake drum.
20.Fit handbrake drum and tighten retaining
screw.
21.Clean propeller shafts and mating faces.
22.Position propeller shafts, align to marks and
tighten bolts to 47 Nm (35 lbf.ft).
23.Clean exhaust silencer and tail pipe mating
faces.
24.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts
and tighten to 25 Nm (18 lbf.ft).
25.Position rear cross member, fit bolts and
tighten to 25 Nm (18 lbf.ft).
26.Refill gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
27.Refill transfer gearbox oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
28.Fit front exhaust pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.
29.Fit gear lever extension, fit clamp bolt and
tighten to 25 Nm (18 lbf.ft).
30.Fit gear lever trim and gear change knob.
31.Connect battery earth lead.
32. Fit battery cover and cooling fan cover and
secure fixings.
Page 489 of 1529
MANUAL GEARBOX - R380
37-18 REPAIRS
22.Ensure gear lever is released from grommet
and no wires or pipes are trapped when
gearbox is lowered.
23.Remove clevis pin and 'C' washer securing low
ratio selector cable to lever and release cable
from lever housing.
24.Remove 2 cable ties securing cable to fuel
pipes. 25.Disconnect 2 Lucars from oil temperature
sensor and disconnect reverse lamp switch
multiplug.
26.Remove banjo bolts securing breather pipes
and discard sealing washers.
27.Remove bolt securing breather pipe 'P' clip and
release breather pipes.
28. If fitted: Disconnect 2 Lucars from differential
lock switch, release and disconnect transfer
box neutral sensor multiplug. Release harness
from 2 retaining clips.
29.Position container to catch oil spillage
30.Remove 2 bolts securing oil cooling pipe
housing to gearbox, release housing and
discard 'O' rings.
CAUTION: Always fit plugs to open
connections to prevent contamination.
31.Using a second jack support the weight of the
engine.
Page 490 of 1529
MANUAL GEARBOX - R380
REPAIRS 37-19
32.Remove 8 bolts securing gearbox to engine.
33.With assistance, remove gearbox from engine.
Refit
1.Clean gearbox to engine mating faces, dowels
and dowel holes.
2.With assistance raise gearbox on jack and
align to clutch and engine.
3.Fit bolts securing gearbox to engine and
tighten to 50 Nm (37 lbf.ft).
4.Clean oil cooling pipe housing mating faces.
5.Lubricate and fit new 'O' rings to oil cooling
pipe housing.
6.Position cooling pipe housing, fit bolts and
tighten to 25 Nm (18 lbf.ft).
7. If fitted: Secure harness in retaining clips,
connect Lucars to differential lock warning
switch and multiplug to transfer box neutral
switch.
8.Position breather pipes and secure 'P' clip with
bolt.
9.Using new sealing washers fit breather pipe
banjo bolts and tighten to 15 Nm (11 lbf.ft).
10.Connect oil temperature sensor Lucars and
reverse lamp switch multiplug.
11.Position low ratio selector cable to housing and
secure with 'C' washer and clevis pin.
12.Secure cable to fuel pipes with new cable ties.
13.Raise gearbox, ensuring gear change lever is
located in grommet.
14.Fit gearbox mountings and tighten bolts to 85
Nm (63 lbf.ft).
15.Fit nuts to gearbox mountings and tighten to 48
Nm (37 lbf.ft).
16.Remove 3 bolts securing support plate to
gearbox. 17.Position clutch slave cylinder and heat shield,
fit bolts and tighten to 25 Nm (18 lbf.ft).
18.Clean handbrake back plate and mating face.
19.Position handbrake back plate, fit bolts and
tighten to 75 Nm (55 lbf.ft).
20.Clean handbrake drum.
21.Fit handbrake drum and tighten retaining
screw.
22.Fit front propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front..
23.Fit rear propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
24.Clean exhaust silencer and tail pipe mating
faces.
25.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts
and tighten to 25 Nm (18 lbf.ft).
26.Fit exhaust front pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.
27.Refit starter motor.
+ CHARGING AND STARTING,
REPAIRS, Starter motor - diesel.
28.Refill gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
29.Refill transfer gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
30.Fit gear lever extension, fit clamp bolt and
tighten to 25 Nm (18 lbf.ft).
31.Fit gear lever trim and gear change knob.
32.Connect battery earth lead.
33.Fit cooling fan cowl and battery cover and
secure fixings.
Page 494 of 1529
MANUAL GEARBOX - R380
REPAIRS 37-23
Cooler - oil - gearbox - Diesel
$% 37.24.02
Remove
1.Remove intercooler.
+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
2.Position absorbent cloth under each gearbox
oil cooler hose connection to collect spillage.
3.Push against coupling release ring and
disconnect both fluid hoses from oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
4.Remove screw securing oil cooler to radiator.
5.Release oil cooler from location on radiator,
and remove the oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.Refit
1.Fit oil cooler to radiator and secure with screw.
2.Ensure connections are clean and secure
hoses to cooler.
3.Fit intercooler.
+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
4.Top up gearbox oil level.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
Page 495 of 1529
MANUAL GEARBOX - R380
37-24 REPAIRS
Cooler - oil - gearbox - V8
$% 37.24.02
Remove
1. If fitted: Remove engine oil cooler.
+ ENGINE - V8, REPAIRS, Cooler -
engine oil.
2.Position absorbent cloth under each gearbox
oil cooler hose connection to collect spillage.
3.Push against coupling release rings and
disconnect both hoses from oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
4.Remove screw securing oil cooler to radiator.
5.Release oil cooler from its location on radiator. 6.Move radiator towards engine sufficiently only
to release gearbox oil cooler from radiator.
7.Remove gearbox oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
Refit
1.Fit gearbox oil cooler to radiator, engage in
location and secure with screw.
2.Ensure connections are clean and secure
hoses to cooler.
3. If fitted: Fit engine oil cooler.
+ ENGINE - V8, REPAIRS, Cooler -
engine oil.
4.Top up gearbox oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
Page 538 of 1529
TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-13
Description
General
The LT 230SE transfer box is mounted at the rear of the gearbox and transmits drive via high or low reduction ratios
to the front and rear axles via the propeller shafts. The high/low ratios are 1.211:1 and 3.32:1 respectively.
Transfer boxes fitted to this model have the prefixes 41D and 42D to the unit serial number. Prefix 41D denotes that
the unit is not fitted with interlock whilst 42D denotes that interlock is fitted.
Vehicles up to 03 model year – Whilst similar to LT230Q transfer boxes fitted to other models, the LT230SE transfer
box has certain engineering modifications incorporated which are as follows:
lUprated torque capacity
lModified front and rear output and cross shaft housings
lIntermediate gear bearing pre-load now controlled by a selective, non-collapsible spacer
lSpeedometer drive and driven gears not fitted for this application
lModified high/low sleeve
lModified front output flange and mud shield
lDifferential lock fitted to certain vehicles, but no longer driver operated
lFixed setting of differential lock warning lamp switch on vehicles fitted with differential lock
Vehicles from 03 model year – The LT230SE transfer box is as described above for vehicles up to 03 model year
with the following modifications:
The following items are introduced on vehicles from 03 model year
lRibs added to main casing to reduce operating noise
lRevised machining process for intermediate gears to reduce operating noise
lBearing retaining nut on the differential carrier has patchlock added to the threads
lInterlock solenoid moved from main casing to selector lever assembly
lIntermediate gears modified with machined internal shoulder and bearing circlips deleted
lDriver operated differential lock
lHigh/Low selector shaft fitted with spring assist
lExisting differential lock switch replaced by 2 new switches of improved design with the additional switch installed
adjacent to the existing switch location.
Construction
The transfer box comprises three main assemblies; the main casing, the front output housing and the rear output
housing. Both output housings and all cover plates are sealed to the main casing by sealant; mud and water ingress
being prevented by mud shields located on the output flanges.
Main casing
The main casing carries the mainshaft input gear, the intermediate gears and the differential, together with the high/
low range gears, selector shaft and fork. The front and rear output housings are bolted to either side of the main
casing.
Transmission neutral sensor
A transmission neutral sensor is fitted on automatic gearbox vehicles for North America and Japan. The sensor is
connected to the BCU and is normally in the open position. The sensor provides an earth path for the BCU which then
interprets the signal and activates an audible warning generated by the IDM if neutral is selected on the transfer box
when the ignition is on.
Transfer box interlock solenoid - Automatic gearbox vehicles
An interlock solenoid is fitted for North America and Japan. The solenoid is located on the top of the transfer box main
casing on vehicles up to 03 model year or on the selector lever assembly on vehicles from 03 model year. The
solenoid is connected to the transfer box relay which, in turn, is controlled by the IDM. The purpose of the solenoid is
to prevent neutral being selected on the transfer box when the ignition key is removed, thereby locking the box in
either high or low ratio.
Page 539 of 1529
TRANSFER BOX - LT230SE
41-14 DESCRIPTION AND OPERATION
Mainshaft input gear
The gearbox output shaft is splined into the mainshaft input gear which is supported by taper roller bearings.
Input gear bearing pre-load is achieved by the use of a selective shim located in the bearing housing.
Intermediate gears
The intermediate gear cluster is supported by the taper roller bearings located at each end of the cluster and runs on
the intermediate shaft which, in turn, is supported at the front and rear by the main casing.
A selective spacer, positioned between the gears, pre-loads the intermediate gear bearings when the intermediate
shaft nut is tightened sufficiently to achieve the correct 'torque to turn' of the intermediate gears.
On vehicles from 03 model year, the circlips used to retain the bearings in the intermediate gear are deleted. The bore
of the intermediate gear is machined with a shoulder at each end to locate the bearings.
Differential assembly
The differential assembly is supported at the front and rear by taper roller bearings, the front bearing outer track is
located in the front output housing and the rear bearing outer track is located in the main casing by the rear output
housing. Bearing pre-load is achieved by means of a selective shim located in the front output housing.
The differential rear shaft carries the low range gear, high/low selector sleeve and hub, high range gear and bush and
the differential rear bearing; these components being secured to the shaft by a special staked nut.
The differential assembly comprises front and rear half carriers with integral shafts and with sun and planet gears
mounted on cross shafts within the half carriers. Dished, non-selective thrust washers control the engagement of the
planet gears with the sun gears, whilst selective thrust washers are used to control engagement of the sun gears and
'torque to turn' of the differential. The differential carrier halves are bolted together, a retaining ring providing positive
location of the cross shafts.
The high/low selector shaft and fork are located at the side of the differential, movement of the shaft, fork and selector
sleeve being controlled by the high/low selector finger. A spring loaded detent ball fitted in the main casing, locates
in grooves in the shaft.
On vehicles from 03 model year, the selector fork is modified and fitted with a spring assister and clips to reduce the
effort required to move the selector lever.
Front output housing
The front output housing carries the front output shaft and flange, high/low cross shaft, housing and selector and on
certain vehicles, the differential lock selector shaft and fork.
The front output shaft is supported in the housing by a single bearing and is splined into the differential front sun gear.
High/low selector
The high/low cross shaft is located in a housing bolted to the top of the output housing and is connected to the high/
low selector finger which locates in a slot in the selector shaft.
High/low detect switch
A high/low detect switch is fitted in the front output housing and connects to earth when low is selected. The switch is
connected to the engine ECM, the SLABS ECU and the EAT ECU. The purpose of the switch is to enable selection
of the hill descent feature and to modify the engine fuelling and automatic gearbox gearshift maps stored within the
respective ECM's and ECU's.
Differential lock - If fitted
The differential lock selector housing is bolted to the top of the front output housing, the selector finger passes through
the housing, locating in a slot in the differential lock selector shaft. The differential lock selector shaft passes through
the selector fork which is located beneath a plate bolted to the side of the output housing. The selector fork engages
the dog clutch sleeve with the differential rear shaft when the splines of the sleeve and differential rear shaft are
aligned. A spring loaded detent ball fitted in the output housing locates in grooves in the shaft.
Page 541 of 1529
TRANSFER BOX - LT230SE
41-16 DESCRIPTION AND OPERATION
Differential lock warning lamp switch - if fitted - Vehicles up to 03 model year
A differential lock warning lamp switch connected to the SLABS ECU and operated by movement of the selector fork
and shaft is screwed into the top of the output housing. The switch connects to earth when the differential lock is
engaged.
Differential lock warning lamp switches - Vehicles from 03 model year
Vehicles from 03 model year are fitted with two differential lock warning lamp switches.
Both switches are of a new design and are fitted into the top of the front output housing. The switches are connected
to the SLABS ECU and are operated by movement of the selector shaft.
Both switches have an aluminium washer which seals the switch to the casing and also sets the switch position,
removing the requirement for a setting procedure.
Both switches are connected in parallel to earth when the differential lock is engaged. This earth is sensed by the
SLABS ECU which illuminates the differential lock warning lamp in the instrument pack.
Differential lock warning lamp - Vehicles up to 03 model year – if fitted
The differential lock warning lamp is located in the instrument pack and provides a warning to the driver when the
ignition is switched on that the differential lock is engaged. The warning lamp illuminates in a Red colour.
With the lock engaged, the traction control and electronic brake distribution warning lamps will also be illuminated.
Disengagement of the differential lock should be carried out with the ignition switched off. The warning lamps must
be extinguished when the ignition is switched on again.
Differential lock warning lamp – vehicles from 03 model year
The differential lock warning lamp is amber coloured and is located in the instrument pack.
When the lock is engaged, the warning lamp is illuminated and the instrument pack sounder emits three audible
chimes. When the lock is disengaged, the warning lamp is extinguished and the instrument pack sounder emits three
audible chimes.
Rear output housing
The rear output housing carries the output shaft and flange. A cable operated transmission brake is attached to the
housing, the brake drum being attached to the output flange.
The rear output shaft is supported in the housing by a single bearing and is splined into the differential rear sun gear.
Lubrication
Lubrication is by splash, oil filler/level and drain plugs being located in the main casing.
Internal pressures caused by thermal expansion and contraction are avoided by the use of a plastic breather pipe
venting the interior of the box to atmosphere. The pipe is attached to the top of the high/low selector housing by a
banjo bolt and is then routed in a continuously rising path into the engine compartment where the open end is secured
by a clip attached to the engine cylinder block.
Oil temperature warning lamp switch
An oil temperature switch is fitted to V8 engine models up to 03 Model Year. In the event of the transfer box oil
approaching maximum recommended working temperature of 145°C (293°F), the switch will close and a warning
lamp in the instrument pack will be illuminated.