transmission LAND ROVER DISCOVERY 1995 Owner's Manual

V8i
1
DESCRIPTION AND OPERATION ENGINE COOLING
Description
The V8i engine uses a pressurised cooling system
and cross flow radiator which is supplied from a
separate header tank. The coolant radiator also
incorporates a section at the left hand end for cooling
the transmission oil and a section at the other end for
cooling the engine oil.The belt driven viscous fan and centrifugal water
pump is located in the engine front cover with ports for
circulation of coolant to both banks of cylinders and
cylinder heads. Coolant returns to the top of the
radiator via ports in the inlet manifold where the
thermostat is mounted horizontally.
Coolant also circulates through the vehicle heating
system and is used to heat air entering the inlet
manifold plenum chamber.
Coolant circulation (engine hot)
1. Cross flow radiator
2. Header tank
3. Viscous fan and water pump
4. Heater pipes
5. Plenum chamber connection
6. Thermostat

26COOLING SYSTEM
4
REPAIR RADIATOR
Service repair no - 26.40.01
Remove
1.Drain cooling system.
See Adjustment,
Coolant
2.Remove viscous coupling and fan assembly.
See Viscous Coupling, Fan Blades, Pulley
and Fan Cowl
3.Release 2 clips and remove fan cowl.
4.Disconnect radiator top hoses.
5.Disconnect four transmission and engine oil
cooler connections to radiator end tanks. Note oil
spillage will occur when connections are
loosened. Blank off exposed oil connections.
6.Disconnect transmission oil temperature sensor.
7.Remove radiator securing brackets from each
side.
8.Remove radiator unit by lifting from its location.
Check condition of rubber mounting pads.Refit
9.Reverse removal procedure.
10.Clean unions and apply sealant.
11.Lubricate new 'O' rings before fitting.
12.Check radiator sealing strips are securely
located.
13.Transfer oil cooler adaptors if fitting new radiator.
14.Ensure that oil cooler connections are tightened
to
30 Nm.before fitting fan blades and cowl.
15.Clean coolant/oil spillage from vehicle.
16.Check all connections for coolant/oil leaks.

CLUTCH
1
DESCRIPTION AND OPERATION DESCRIPTION
The clutch unit fitted with the manual transmission,
comprises a single dry plate friction disc and
diaphragm spring clutch unit, secured to the engine
flywheel.OPERATION
The unit is operated hydraulically by the clutch master
cylinder 12 and a slave cylinder 13 attached to the
transmission bell housing.
1. Crankshaft and flywheel
2. Friction plate
3. Clutch cover
4. Diaphragm spring
5. Pressure plate
6. Fulcrum posts (9) for diaphragm spring
7. Bearing rings (2) for diaphragm spring
8. Retraction links and bolts (3) for pressure plate
9. Release bearing
10. Release lever11. Release lever pivot post
12. Master cylinder
13. Slave cylinder
14. Master cylinder pedal pushrod
15. Primary shaft and taper bearing (in gearbox)
16. Gearbox front cover
17. Primary shaft flywheel bush
18. Pedal pivot and return spring
19. Hydraulic damper (Diesel only)

CLUTCH
1
FAULT DIAGNOSIS CLUTCH ASSEMBLY CONDITIONS
For the clutch to operate correctly as described and
illustrated in the "Description and Operation", it is
important the following conditions are satisfied:-
A. The primary shaft 15 must be free in the
crankshaft spigot bush 17.
B. The friction plate 2 must be able to slide easily
on the splines on the primary shaft 15, to a
position where it does not contact either the
flywheel or the pressure plate.
C. The friction plate must not be distorted or the
linings contaminated with oil, which may cause it
to stick or continue to run in contact with the
flywheel or pressure plate.
A number of faults can develop in the operation of the
clutch for a variety of reasons and although most
faults are due to normal wear at high mileage,
problems can also occur if the unit has been renewed
by an unskilled operator.
Recognising and diagnosing a particular clutch fault is
therefore of paramount importance in ensuring, that
the problem is rectified at the first attempt.
Problems which develop in the clutch are as follows:-
A. Clutch spin/drag
B. Clutch slip
C. Clutch judder/fierceCLUTCH SPIN - DRAG
Symptoms
Clutch spin is that, with engine running and clutch
pedal depressed, the gears cannot be immediately
engaged without making a grinding noise. This
indicates the clutch is not making a clean break.
However, if the clutch pedal is held depressed for
several seconds the friction plate will eventually break
free from the engine and the gear will engage silently.
Clutch spin as it becomes more severe develops into
clutch drag, making the silent engagement of a gear
impossible, regardless of how long the pedal is held
depressed.
CLUTCH SLIP
Symptoms
Clutch slip is most evident climbing a hill or when the
vehicle is moving off from stationary with a heavy
load. As the clutch is released slip occurs between the
engine and the transmission, allowing the engine
speed to increase without a corresponding increase in
vehicle speed.
Clutch slip can develop to the stage where no power
is transmitted through the clutch as the pedal is
released.
CLUTCH JUDDER - FIERCE
Symptoms
Clutch judder or fierce engagement, like slip, is most
likely to occur when the vehicle is moving off from
stationary. As the clutch pedal is released the vehicle
will move rapidly or in a series of jerks, which can not
be controlled even by careful operation of the clutch
by the driver.
It should be noted that a vehicle may display all the
symptoms or any combination of the symptoms
described, depending on the driving conditions vehicle
load and operating temperatures.

R380
1
DESCRIPTION AND OPERATION MANUAL TRANSMISSION
Description
The all synchromesh five speed manual gearbox unit,
is married to a LT230T two speed transfer gearbox.
All the gears including reverse run on needle roller
bearings and the main, layshaft and primary shafts
are supported by tapered roller bearings.The whole of the geartrain is lubricated through
drillings in the shafts, supplied by a low pressure
pump driven from the rear of the layshaft. The gear
change has a single rail selector and spool type
interlock. The main and transfer gearboxes ventilate
through nylon pipes, which terminate high up in the
engine compartment to prevent water entry when the
vehicle is operating in adverse conditions.
1. Mainshaft 1st gear
2. Mainshaft 2nd gear
3. Mainshaft 3rd gear
4. Primary input shaft
5. Mainshaft 5th gear
6. Layshaft
7. Mainshaft
8. Lubrication pump9. Drain plug
10. Ventilation pipe
11. Single rail gear shift
12. 1st/2nd synchromesh
13. Oil seals
14. 3rd/4th synchromesh
15. 5th gear synchromesh

R380
1
FAULT DIAGNOSIS MANUAL GEARBOX
Symptom - Gear jumps out of engagement (any
forward gear)
1.Check condition and security of transmission
and engine mountings.
2.Check in situ, gear lever and selector
adjustments.
3.In situ, remove gearshift and check selector rail
yoke security.
Also check selector detent spring tension and
both spool retainers.
Suspect internal fault
See remove and overhaul procedure.
4.Check action/operation of main selector rail and
forks.
5.Check condition of synchromesh and gear dog
teeth.
6.Check main and layshaft end floats bearings and
adjustments.
7.Check condition of all gearbox components,
ensure clearances and adjustments are correct
on reassembly.
Symptom - Reverse gear only jumps out of
engagment
1.Check condition and security of transmission
and engine mountings.
2.Check in situ, gear lever and selector
adjustments.
3.In situ, remove gearshift and check selector rail
yoke security.
Also check selector detent spring tension and
both spool retainers.
Suspect internal fault
See remove and overhaul procedure.
4.Check action/operation of main selector rail and
reverse lever.
5.Check condition of reverse gear, angled
bearings and shaft.
6.Check condition of all gearbox components,
ensure clearances and adjustments are correct
on reassembly.Symptom - Excessive force required to engage or
change gear, vehicle stationary or moving.
1.Check lubricant specification and level, if low do
not top up at this stage.
2.In situ, lubricate gear mechanism, and check
selector adjustments.
3.In situ, remove gearshift and check selector rail
is free and that the yoke is secure. Also check
selector detent spring tension and both spool
retainers.
4.Drain lubricant and check for contamination or
metal particles.
Suspect worn synchromesh unit or baulk rings
on affected gears. See remove and overhaul
procedure.
Symptom - Noisy gear engagement, vehicle
stationary.
See CLUTCH, Fault diagnosis, Clutch
Noise - Mechanical Faults
Symptom - Noisy gear selection, vehicle moving.
1.Confirm that clutch operation is satisfactory.
2.Establish which gear/gears is causing noise.
3.Check lubricant specification and level, if low do
not top up at this stage.
4.Drain lubricant and check for contamination or
metal particles.
Suspect worn synchromesh. See remove and
overhaul procedure.
5.Check condition of synchromesh unit, springs
and cones for distortion and wear. Also check
dog teeth for damage and cone mating surface
on gear for signs of overheating.
6.Check condition of all gearbox components,
ensure clearances and adjustments are correct
on reassembly.
Symptom - Noise from gearbox in neutral, which
changes tone or becomes worse when clutch is
depressed.
See CLUTCH, Fault diagnosis, Clutch
Noise - Mechanical Faults

R380
1
REPAIR R380 MANUAL GEARBOX
Service repair no - 37.20.02
Remove
WARNING: Where the use of a
transmission hoist is necessary, it is
absolutely essential to follow the
manufacturer's instructions to ensure safe and
effective use of equipment.
1.Install vehicle on a ramp [hoist].
2.Disconnect battery earth lead.
3.Remove centre console.
See CHASSIS AND
BODY, Repair, Centre Console
4.Remove sound insulation from top of
transmission tunnel.
5.Remove bolt and remove upper gear lever.
6.Remove screws securing gear selector lever and
high/low selector lever draft excluders.
7.Remove draft excluder clamp rings.
8.Remove handbrake cable clevis pin clip and
clevis pin.
9.Remove 'C' clip and cable adjuster.
10.Select low range to prevent gear lever fouling
tunnel when removing gearbox.
11.Remove bolt securing gearbox breather pipe clip
to cylinder block.
12.Remove bolts securing fan cowl to radiator.
13.Release fan cowl from radiator and lay over fan
blades.
14.Raise ramp [hoist].
15.Drain oil from main gearbox and transfer
gearbox.
See SECTION 10, Maintenance,
Under Vehicle Maintenance
16.Remove exhaust front pipe(s).See MANIFOLD
AND EXHAUST SYSTEM, Repair, Exhaust
System Complete
17.Release intermediate exhaust pipe(s) from
mountings and tie aside.
18.Remove bolts securing clutch slave cylinder.
19.Release slave cylinder from clutch housing and
collect spacer.
20.Mark propeller shaft drive flange relationships for
reassembly.
21.Disconnect front and rear propeller shafts from
transfer gearbox. Tie shafts aside.
22.Remove clamp and disconnect speedometer
cable from transfer gearbox.
23.Release handbrake cable from transmission
tunnel.
24.Temporarily support transmission in a way which
enables the crossmember to be removed and a
hoist cradle to be fitted.

37MANUAL GEARBOX
2
REPAIR 25.Remove nuts and bolts securing transmission
cross-member to chassis.
26.Remove nuts and bolts securing cross-member
mountings to transmission.
27.Remove cross-member.
28.Manufacture an adapter plate to dimensions
given in service tool section and attach it to a
transmission hoist. To achieve balance of the
transmission unit when mounted to hoist, it is
essential that pointA,is situated over lifting hoist
ram. Drill holesBto suit hoist table. Secure the
transmission unit cradle at pointCusing the
lower bolts retaining transfer gearbox rear cover.
Raise hoist just enough to take weight of
transmission.
29.Lower hoist sufficiently to allow transfer gearbox
selector lever to clear transmission tunnel
aperture.
30.Disconnect differential lock switch connectors.
31.Disconnect reverse lamp switch connectors.
32.Remove clips securing gearbox breather pipes
to harness.
33.Support engine under sump with a jack.
CAUTION: Use a wooden block to protect
sump.
34.Remove bell housing nuts.
35.Withdraw transmission whilst ensuring all
connections to engine and chassis are released.36.Remove transmission assembly from hoist
cradle and position safely on a bench.
37.Remove breather pipes. Discard pipe union
sealing washers.
38.Remove 'Nyloc' nut, and remove bolt, securing
lever to high/low shaft.
39.Collect spacer washer.
40.Remove 2 clips and remove differential lock
lever link.
41.Remove lower locknut from high/low operating
rod.
42.Place a sling round transfer box and attach to
hoist.
43.Remove nut and 5 bolts securing transfer
gearbox to extension housing.
44.Withdraw transfer gearbox.

R380
3
REPAIR Assembling transfer gearbox to main gearbox
45.Clean extension housing and transfer gearbox
mating faces.
46.Ensuring loose upper dowel is fitted, hoist
transfer gearbox into position.
47.Fit and tighten nut and bolts to
34Nm.
48.Connect high/low operating rod, fit and tighten
locknut.
49.Fit link to differential lock lever and secure with 2
clips
50.Align lever to high/low shaft, position washer, fit
bolt and new Nyloc nut. Tighten to
2Nm.
51.Position breather pipes, secure pipe unions
using new sealing washers. Tighten unions to
15Nm.
Fitting transfer gearbox and main gearbox
assembly to engine
52.Position transmission assembly to hoist cradle.
53.Clean bell housing and engine mating faces.
54.Temporarily fit gear lever and select any gear in
main gearbox to facilitate entry of gearbox input
shaft.
55.Position and raise hoist, and fit transmission to
engine whilst keeping wires and pipes clear to
prevent trapping.
56.Fit and tighten nuts securing transmission to
engine.
57.Connect reverse lamp switch connectors and
differential lock switch connectors.
58.Secure breather pipes to harness with clips.
59.Position temporary support.
60.Remove 2 bolts securing lifting cradle to
transmission and remove hoist. Apply Loctite
290 to bolts and refit bolts.
61.Position cross-member, loosely fit nuts and bolts
securing cross-member mountings to
transmission.62.Raise transmission, align cross-member and
loosely fit nuts and bolts securing cross-member
to chassis.
63.Tighten all securing nuts and bolts. Remove
supporting jack from under sump.
64.Remove temporary support.
65.Fit handbrake cable through transmission tunnel
and secure gaiter.
66.Connect speedometer cable to transfer gearbox.
67.Line up marks and connect front and rear
propeller shafts.
68.Clean spacer, clutch slave cylinder and gearbox
mating faces.
69.Position spacer and slave cylinder, fit bolts.
Tighten to
25Nm.
70.Untie intermediate exhaust pipe(s) and refit
exhaust front pipe(s).
See MANIFOLD AND
EXHAUST SYSTEM, Repair, Exhaust System
Complete
71.Refill main gearbox and transfer gearbox with oil.
See SECTION 10, Maintenance, Under
Vehicle Maintenance
72.Lower ramp [hoist].
73.Fit fan cowl, fit and tighten bolts.
74.Align breather pipe clip to cylinder block, fit and
tighten bolts.
75.Fit handbrake cable adjuster and secure with 'C'
clip.
76.Align cable trunnion to handbrake lever, fit clevis
pin and secure with clip.
77.Check handbrake adjustment.
See SECTION
10, Maintenance, Vehicle Interior
78.Fit upper gear lever, fit and tighten bolt.
79.Fit gear selector lever and high/low selector
lever draft excluders.
80.Position draft excluder clamp rings, fit and
tighten screws.
81.Refit sound insulation.
82.Refit centre console.
See CHASSIS AND
BODY, Repair, Centre Console
83.Connect battery earth lead.

TRANSFER GEARBOX
1
REPAIR LT230T TRANSFER GEARBOX
Service repair no - 41.10.25
Remove
Adaptor plate for removing transfer gearbox
The transfer gearbox is removed from underneath the
vehicle. Using a transmission hoist with an adaptor
plate for securing the transfer gearbox to the hoist.
The adaptor can be manufactured locally to the
drawing below.
WARNING: When using a transmission
hoist it is essential to follow the hoist
manufacturer's instructions.