1995 LAND ROVER DISCOVERY catalytic converter

17EMISSION CONTROL
6
REPAIR CATALYTIC CONVERTER/FRONT PIPE - 4.0 V8
Service repair no - 17.50.09
WARNING: The removal of the exhaust
system must only be carried out when the
engine is cold.
Remove
1.Disconnect battery negative lead.
2.Raise vehicle on ramp.
3.Remove oxygen sensors
See Heated Oxygen
Sensor (HO2S) - 4.0 V8
4.Remove 4 nuts/bolts securing front anti-roll bar
brackets.
5.Remove 6 nuts securing front pipe flanges to
manifolds.
6.Remove 2 nuts securing front pipe to
intermediate pipe.
7.With assistance, release front pipe from manifold
flanges.8.With assistance, release front pipe from
intermediate pipe.
9.With assistance, lower anti-roll bar.
10.With assistance, remove exhaust front pipe.
11.Remove flange gaskets and discard.
Refit
12.Reverse removal procedure.

MANIFOLD AND EXHAUST SYSTEM
1
DESCRIPTION AND OPERATION CATALYTIC CONVERTERS - V8i
Description
Catalytic converters which form part of the engine
emission control system, are designed to 'clean' the
exhaust gases, by closely controlling the fuel air ratio
delivered to the engine and converting the residual
exhaust compounds into products more acceptable to
the environment.
The front section of the exhaust system to each
cylinder bank contain the ceramic elements of the
catalytic converters. The oxygen sensors which
transmit information to the fuel ECU for control of the
mixture, are located in the exhaust down pipes.
The Hydrocarbons (HC), Nitogen oxides (NO
x) and
Carbon monoxide (CO) emitted by the engine react
with the catalytic element and exhaust temperature to
convert the toxic gas, into Nitrogen (N), Carbon
dioxide (CO
2) and water vapour.Should the engine be supplied with a rich mixture
causing high CO in the exhaust gas, the ceramic
element will become coated and the useful life of the
catalyst reduced. If the mixture is too weak, excess
oxygen in the exhaust gas will cause the catalysts to
burn out.
1. Catalysts
2. Lambda oxygen sensors

41TRANSFER GEARBOX
2
REPAIR Remove
1.Site vehicle on a ramp [hoist].
2.Disconnect battery negative lead.
3.Remove fan cowl from radiator.
4.Remove transfer gear lever knob and gaiter.
5.Raise vehicle on ramp [hoist].
6.Drain oil and refit plug.
7.Detach heat shield at front exhaust pipe to
manifold.
8.Disconnect electrics to Lambda sensors.
9.Remove catalytic converter assembly.
10.Remove chassis crossmember from under
gearbox.
11.Remove heat shield from speedometer cable at
transfer gearbox.
12.Remove clamp and disconnect speedometer
cable from transfer gearbox. Tie cable to one
side.
13.Mark for reassembly then disconnect propeller
shaft to output flange, tie to one side.
14.Repeat on front propeller shaft to output flange.
15.Remove bolts retaining silencer front and rear
securing brackets and tie silencer to one side.
16.Place four 30mm long spacers between top of
hoist and adaptor plate, at securing points, and
secure adaptor plate to hoist.17.Remove four central bolts from transfer gearbox
bottom cover, move hoist into position and
secure adaptor plate to transfer gearbox.
18.Adjust hoist to take weight of transfer gearbox.
19.Remove tie bar, transfer gearbox to main
gearbox.
20.Remove nuts and bolts securing right transfer
gearbox mounting bracket to chassis.
21.Repeat for left mounting bracket. Removal of
these fixings will also free speedometer
transducer bracket.
22.Remove right side mounting bracket to flexible
mounting rubber.
23.Lower hoist until rear brake drum clears
passenger footwell. Check engine does not
crush any components while lowering.
24.Loosen park brake adjustment nut.
25.Remove park brake drum.
26.Remove park brake assembly complete from
rear output flange.
27.Disconnect leads from transfer gearbox
temperature sensor and differential lock warning
light switch.
28.Remove banjo bolt from breather pipe, retrieve
sealing washers and lay pipe aside.
29.Remove split [cotter] pin and washers securing
differential lock to connecting rod and disconnect
rod from lever.
30.Select low range transfer gearbox position.
31.Remove high/low rod lower lock nut and remove
rod from yoke.
32.Position hoist jack channel under bell housing.
33.Using wooden block support the main gearbox
and bell housing.
34.Remove upper and lower bolts securing transfer
gearbox to main gearbox.
35.Fit guide studs 18G 1425 to main gearbox and
move transfer gearbox rearwards to detach.

44AUTOMATIC GEARBOX
2
REPAIR 1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead.
3.Remove fan cowl securing screws and release
cowl from radiator.
4.Loosen securing clip and disconnect air flow
hose from plenum chamber.
5.Disconnect stepper motor hose from top of
plenum chamber.
6.Disconnect kickdown cable from throttle linkage
and release from clipping.7.Release two gearbox breather pipes from clip
located on lifting eye at rear of right hand
cylinder head.
8.Remove dipstick from main gearbox oil filler
tube.
9.Working inside vehicle detach transfer gear lever
gaiter from console, unscrew knob and withdraw
gaiter and knob.
10.Raise vehicle on ramp [hoist].
11.Remove drain plugs and drain oil from transfer
gearbox and main gearbox. Refit plugs.
12.Detach heat shield at front exhaust pipe to
manifold.
13.Disconnect electrics to Lambda sensors.
14.Remove catalytic converter assembly.
15.Remove chassis cross-member from under
gearbox.16.Remove heat shield from speedometer cable at
transfer gearbox.
17.Remove clamp and disconnect speedometer
cable from transfer gearbox. Tie cable to one
side.
18.Mark for reassembly propeller shaft to transfer
gearbox mating flanges.

44AUTOMATIC GEARBOX
8
REPAIR INHIBITOR SWITCH
Service repair no - 44.15.19
Remove
1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead. Raise vehicle.
3.Disconnect inhibitor switch multi plug.
4.Remove inhibitor switch retaining plate.
5.Remove inhibitor switch.
6.Remove 'O' ring seal.
7.Clean inhibitor switch.
Refit
8.Clean mating face on casing.
9.Fit and lubricate new 'O' ring seal to switch.
10.Fit switch to casing.
11.Secure with retaining plate and bolt.
12.Connect multiplug to harness.
13.Reconnect battery and remove vehicle from
ramp [hoist].
SELECTOR SHAFT OIL SEAL
Service repair no - 44.15.34
Renew
1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead.
3.Raise vehicle.4.Detach heat shield at front exhaust pipe to
manifold.
5.Disconnect electrics from Lambda sensors.
6.Remove catalytic converter assembly.
7.Remove chassis cross-member from under
gearbox.
8.Engage low range gear in the transfer gearbox.
9.Support transfer gearbox with a jack or
transmission hoist.
10.Remove transfer gearbox chassis mounting
bracket nuts and bolts. Note location of
speedometer cable bracket for refit.
11.Lower transmission to allow access to selector
shaft.
12.Remove selector lever from shaft.
13.Remove selector shaft seal from casing.
14.Clean selector shaft and seal mating faces.
15.Fit centre section of special tool LST 114 over
selector shaft.
16.Lubricate new oil seal and position seal on tool.
17.Fit tool outer sleeve and screw on nut to drive
seal into housing.
18.Remove tool from shaft.
19.Refit selector lever to shaft.
20.Raise transmission and secure mounting
brackets to chassis. Ensure speedometer cable
bracket is secured. Tighten bolts to
30Nm.
21.Remove support jack.
22.Refit chassis cross-member.
23.Refit catalytic converter assembly.
24.Connect electrics to Lambda sensors.
25.Connect heat shield front pipe to manifold.
26.Connect battery.
27.Check/top up gearbox oil level.

ZF
9
REPAIR OIL SUMP
Service repair no - 44.24.05
Remove
1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead.
3.Raise vehicle.
4.Drain oil and refit plug with new seal.
5.Detach heat shield at front exhaust pipe to
manifold.
6.Disconnect electrics from Lambda sensors.
7.Remove catalytic converter assembly.
8.Remove chassis cross-member from under
gearbox.
9.Disconnect dipstick tube at oil sump. Loosen
securing bolt at bell housing and move dipstick
aside.
10.Remove clamps securing oil sump. Note their
locations for refit and withdraw sump.
11.Remove gasket and clean gasket mating faces.Refit
12.Refit oil sump using a new gasket.
13.Connect dipstick tube to oil sump and tighten
bolt at bell housing.
14.Refit chassis cross member.
15.Refit catalytic converter assembly
16.Connect electrics to Lambda sensors.
17.Connect heat shield front pipe to manifold.
18.Connect battery.
19.Refill gearbox using correct grade of oil.
See
LUBRICANTS, FLUIDS AND CAPACITIES,
Information, Recommended Lubricants and
Fluids

44AUTOMATIC GEARBOX
10
REPAIR OIL SCREEN
Service repair no - 44.24.07
Renew
1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead.
3.Raise vehicle.
4.Drain oil and refit plug with new seal.
5.Detach heat shield at front exhaust pipe to
manifold.
6.Disconnect electrics from Lambda sensors.
7.Remove catalytic converter assembly.
8.Remove chassis cross-member from under
gearbox.
9.Disconnect dipstick tube at oil sump. Loosen
securing bolt at bell housing and move dipstick
aside.
10.Remove clamps securing oil sump. Note their
locations for refit and withdraw sump.
11.Remove gasket and clean gasket mating faces.
12.Remove securing screws and detach oil screen
and suction pipe, taking care to retain suction
pipe spacer, discard 'O' ring seal.13.Detach suction pipe from oil screen, discard 'O'
ring seal.
14.Clean oil screen and blow out with airline.
15.Clean suction pipe.
16.Fit new 'O' ring seals to oil screen using light
grease to aid assembly.
17.Fit oil screen and suction pipe with spacer and
secure with three bolts.
18.Refit oil sump using a new gasket.
19.Connect dipstick tube to oil sump and tighten
bolt at bell housing.
20.Refit chassis cross-member.
21.Refit catalytic converter assembly
22.Connect electrics to Lambda sensors.
23.Connect heat shield front pipe to manifold.
24.Connect battery.
25.Refill gearbox oil system using correct grade of
oil.
See LUBRICANTS, FLUIDS AND
CAPACITIES, Information, Recommended
Lubricants and Fluids

ZF
11
REPAIR CONTROL UNIT
Remove
1.Site vehicle on a four post ramp [hoist].
2.Disconnect battery negative lead.
3.Raise vehicle.
4.Drain oil and refit plug with new seal.
5.Detach heat shield at front exhaust pipe to
manifold.
6.Disconnect electrics from Lambda sensors.
7.Remove catalytic converter assembly.
8.Remove chassis cross-member from under
gearbox.
9.Disconnect dipstick tube at oil sump. Loosen
securing bolt at bell housing and move dipstick
aside.
10.Remove clamps securing oil sump. Note their
locations for refit and withdraw sump.
11.Remove gasket and clean gasket mating faces.
12.Remove securing screws and detach oil screen
and suction pipe, taking care to retain suction
pipe spacer, discard 'O' ring seal.
13.Remove securing screws and detach control unit
from casing.