1996 LAND ROVER DEFENDER oil pressure

70BRAKES
10
REPAIR FRONT BRAKE CALIPERS
Service repair no - 70.55.05
Service repair no - 70.55.16
Before starting repair refer to general brake service
practice
See General Brake Service Practice.
Remove
1.Remove front road wheels.
2.Expose flexible brake hose by moving coiled
protective covering.
3.Using a recognised hose clamp, clamp hose to
prevent loss of brake fluid.
4.Disconnect rigid brake pipe from flexible hose,
seal exposed ends to prevent ingress of dirt.
5.Remove split pin, retaining pins and springs,
withdraw pads. If refitting pads, identify them for
assembly to original locations.
6.Remove 2 bolts and withdraw caliper from swivel
housing.
WARNING: Do not separate caliper halves
7.Clean outer surfaces of caliper using aerosol
brake cleaner.
8.Using special toolLRT-70-500, clamp pistons in
inboard half of caliper. Gently, keeping fingers
clear, and withCAUTION, apply air pressure to
fluid inlet port to expel pistons. It is unlikely that
pistons will expel at same time, regulate rate
with a suitable piece of wood between
appropriate piston and caliper.
9.Finally remove pistons, identifying them with
their respective bores.
10.Remove wiper seal retainer by inserting a blunt
screwdriver between retainer and seal. Pry
retainer carefully from mouth of bore.
11.Taking care not to damage seal grooves, extract
wiper seal and fluid seal.
12.Clean bores, pistons and seal grooves using
clean brake fluid only. If caliper or pistons are
corroded, or their condition is not perfect, new
parts must be fitted.

82AIR CONDITIONING
2
DESCRIPTION AND OPERATION Operation
Evaporator unit and expansion valve
High pressure liquid refrigerant is delivered to the
expansion valve which is the controlling device for the
air conditioning system. A severe pressure drop
occurs across the valve and as the refrigerant flows
through the evaporator it picks up heat from the
ambient air, boils and vaporizes. As this change of
state occurs, a large amount of latent heat is
absorbed. The evaporator is therefore cooled and as
a result heat is extracted from the air flowing across
the evaporator. The refrigerant leaves the evaporator,
on its way to the compressor, as a low pressure gas.
An evaporator sensor measures the air temperature at
the evaporator and engages or disengages the
compressor clutch to prevent icing of the air ways.
Compressor
The compressor, a pump specially designed to raise
the pressure of the refrigerant, is mounted on the front
of the engine and is driven by an independent drive
belt from the crankshaft pulley. The compressor draws
vaporized refrigerant from the evaporator. It is
compressed with a resulting rise in temperature and
passed on to the condenser as a hot, high pressure
vapour.
Condenser
The condenser is mounted directly in front of the
radiator and consists of a refrigerant coil mounted in a
series of thin cooling fins to provide the maximum
heat transfer. Air flow across the condenser is induced
by vehicle movement and assisted by two electric fans
attached to the frame of the condenser. The
refrigerant high pressure vapour enters the condenser
inlet on the RH side. As the vapour passes through
the condenser coils the air flow, assisted by the two
fans, carries the latent heat away from the condenser.
This induces a change of state resulting in the
refrigerant condensing into a high pressure warm
liquid. From the condenser, the refrigerant continues
to the receiver/ drier.
Receiver/drier
This component acts as a reservoir and is used to
hold extra refrigerant until it is needed by the
evaporator. The drier within the receiver unit contains
a filter and dessicant (drying material) which absorb
moisture and prevent dessicant dust from being
carried with the refrigerant into the system.AIR CONDITIONING AND HEATER CONTROLS -
LH DRIVE
1. Temperature control
Move the lever upwards (RED) to increase air
temperature, or downwards (BLUE) to reduce air
temperature.
2. Air conditioning switch
Press the switch (indicator lamp illuminates) to
activate the air conditioning. Press again to switch off.
3. Air recirculation control
Move the lever fully upwards to activate air
recirculation. Move the lever fully downwards to
cancel recirculation.
NOTE: Prolonged recirculation may cause
the windows to mist up.
4. Air distribution control
Lever fully up - air to windscreen vents (also provides
some air to the footwell).
Lever midway - air to fascia vents (also provides some
air to the footwell).
Lever fully down - air to footwell vents (also provides
some air to the windscreen).

82AIR CONDITIONING
2
ADJUSTMENT SERVICING PRECAUTIONS
Care must be taken when handling refrigeration
system components. Units must not be lifted by their
hoses, pipes or capillary lines. Hoses and lines must
not be subjected to any twist or stress. Ensure that
hoses are positioned in their correct run before fully
tightening the couplings, and ensure that all clips and
supports are used. Torque wrenches of the correct
type must be used when tightening refrigerant
connections to the stated value. An additional spanner
must be used to hold the union to prevent twisting of
the pipe.
Before connecting any hose or pipe ensure that
refrigerant oil is applied to the seat of the new '0' ring
but not to the threads.
Check the oil trap for the amount of oil lost.
All protective plugs on components must be left in
place until immediately prior to connection.
The receiver/drier contains desiccant which absorbs
moisture. It must be positively sealed at all times.
CAUTION: Whenever the refrigerant
system is opened, the receiver/drier must
be renewed immediately before evacuating
and recharging the system.
Use alcohol and a clean cloth to clean dirty
connections.
Ensure that all new parts fitted are marked for use
withR134a.
Refrigerant oil
Use the approved refrigerant lubricating oil - Nippon
Denso ND-OIL 8.
CAUTION: Do not use any other type of
refrigerant oil.
Refrigerant oil easily absorbs water and must not be
stored for long periods. Do not pour unused oil back
into the container.
When renewing system components, add the
following quantities of refrigerant oil:
Condenser 40ml..........................................................
Evaporator 80ml..........................................................
Pipe or hose 20ml........................................................
Receiver/drier 20ml......................................................Total quantity of refrigerant oil in system = 140ml
A new compressor is sealed and pressurised with
Nitrogen gas, slowly release the sealing cap, gas
pressure should be heard to release as the seal is
broken.
NOTE: A new compressor should always
have its sealing caps in place and these
must not be removed until immediately
prior to fitting
A new compressor is supplied with an oil fill of 140ml.
A calculated quantity of oil must be drained from a
new compressor before fitting.
To calculate the quantity of oil to be drained:
1.Remove sealing plugs from the OLD
compressor.
2.Invert compressor and gravity drain oil into
measuring cylinder. Rotating the compressor
clutch plate will assist complete draining.
3.Note the quantity of oil drained (Yml).
4.Calculate the quantity (Qml) of oil to be drained
from the NEW compressor using the following
formula:
Xml - (Yml + 20ml) = Qml
Rapid refrigerant discharge
When the air conditioning system is involved in
accident damage and the circuit is punctured, the
refrigerant is discharged rapidly. The rapid discharge
of refrigerant will also result in the loss of most of the
oil from the system. The compressor must be
removed and all the remaining oil in the compressor
drained and refilled as follows:
1.Gravity drain all the oil, assist by rotating the
clutch plate (not the pulley).
2.Refill the compressor with 90ml of new
refrigerant oil.
3.Plug the inlet and outlet ports.
Servicing Equipment
The following equipment is required for full servicing
of the air conditioning system.
Recovery, recycling and charging station
Leak detector
Thermometer +20°C to -60°C
Safety goggles and gloves

AIR CONDITIONING
3
ADJUSTMENT REFRIGERANT RECOVERY, RECYCLING,
RECHARGING
WARNING: The air conditioning system is
charged with a high pressure, potentially
toxic refrigerant. Repairs or servicing must
only be carried out by an operator familiar with
both the vehicle system and the charging and
testing equipment.
All operations must be carried out in a
well-ventilated area away from open flame and
heat sources.
Always wear safety goggles and gloves when
opening refrigerant connections.
WARNING: Wear eye and hand safety
protection. Open connections slowly in
case liquid or pressure is present. Allow to
bleed off slowly.
CAUTION: Overcharging air conditioning
system will cause excessive head
pressure.
An air conditioning portable Refrigerant Recovery
Recycling Recharging Station for use with R134a
refrigerant incorporates all the features necessary to
recover refrigerant R134a from the air conditioning
system, to filter and remove moisture, to evacuate and
recharge with the reclaimed refrigerant. The unit can
also be used for performance testing and air
conditioning system analysis.
The operator must adhere to the equipment
manufacturers' instructions.
Recovery and recycling
1.Connect a Refrigerant Station to the high and
low pressure servicing connections.
2.Operate the refrigerant recovery system
according to the manufacturers instructions.
3.Measure the amount of oil discharged from the
system. Add an equal amount of new refrigerant
oil to compressor before evacuation sequence.
WARNING: Refrigerant must always be
recycled before reuse, to ensure that the
purity of the refrigerant is high enough for
safe use in the air conditioning system. Recycling
should always be carried out with equipment
which is design certified by Underwriter
Laboratory Inc. for compliance with SAE-J1991.
Other equipment may not recycle refrigerant to
the required level of purity.
A R134a Refrigerant Recovery Recycling
Recharging Station must not be used with any
other type of refrigerant.
Refrigerant R134a from domestic and commercial
sources must not be used in motor vehicle air
conditioning systems.
Evacuation and recharging
1.Add refrigerant oil to compressor if necessary.
2.Renew the receiver/drier.
CAUTION: When a major repair has been
carried out, a leak test should be carried
out using inert gas.
3.Connect a Refrigerant Station to the high and
low pressure servicing connections.
CAUTION: Whenever the refrigerant
system is opened, the receiver/drier must
be renewed immediately before evacuating
and recharging the system.
4.Operate the refrigerant evacuation system
according to the manufactures instructions.
NOTE: If the vacuum reading is below
700mmHg after 15 minutes, suspect a leak
in the system. Partially recharge the
system and check for leaks using an electronic
leak tester. Check suction lines first, then run the
compressor for 5 minutes and then check the high
pressure lines.
CAUTION: The system must be Evacuated
immediately before recharging
commences. Delay between Evacuation
and Recharging is not permitted.

82AIR CONDITIONING
6
ADJUSTMENT SYSTEM TEST
1.Place the vehicle in a ventilated, shaded area
free from excessive draught, with the doors and
windows open.
2.Check that the surface of the condenser is not
restricted with dirt, leaves, flies, etc. Do not
neglect to check the surface between the
condenser and the radiator. Clean as necessary.
3.Switch on the ignition and the air conditioner air
flow control. Check that the blower is operating
efficiently at low, medium and high speeds.
Switch off the blower and the ignition.
4.Check that the evaporator condensate drain
tubes are open and clear.
5.Check the tension of the compressor driving belt,
and adjust if necessary.
6.Inspect all connections for the presence of
refrigerant oil. If oil is evident, check for leaks,
and repair as necessary.
NOTE: The compressor oil is soluble in
Refrigerant R134a and is deposited when
the refrigerant evaporates from a leak.
7.Start the engine.
8.Set the temperature controls to cold and switch
the air conditioner blower control on and off
several times, checking that the magnetic clutch
on the compressor engages and releases each
time.
9.With the temperature control at maximum
cooling and the blower control at high speed,
warm up the engine and fast idle at 1000
rev/min.
10.Repeat at 1800 rev/min.
11.Gradually increase the engine speed to the high
range and check the sight glass at intervals.
12.Check for frosting on the service valves.
13.Check the high pressure hoses and connections
by hand for varying temperature. Low
temperature indicates a restriction or blockage at
that point.
14.Switch off the air conditioning blower and stop
the engine.
15.If the air conditioning equipment is still not
satisfactory, carry out a pressure test as
previously described in this section.PRECAUTIONS IN HANDLING REFRIGERANT
LINES
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
1.When disconnecting any hose or pipe
connection the system must be discharged of all
pressure. Proceed cautiously, regardless of
gauge readings. Open connections slowly,
keeping hands and face well clear, so that no
injury occurs if there is liquid in the line. If
pressure is noticed, allow it to bleed off slowly.
2.Lines, flexible end connections and components
must be capped immediately they are opened to
prevent the entrance of moisture and dirt.
3.Any dirt or grease on fittings must be wiped off
with a clean alcohol dampened cloth. Do not use
chlorinated solvents such as trichloroethylene. If
dirt, grease or moisture cannot be removed from
inside the hoses, they must be replaced with
new hoses.
4.All replacement components and flexible end
connections must be sealed, and only opened
immediately prior to making the connection.
5.Ensure the components are at room temperature
before uncapping, to prevent condensation of
moisture from the air that enters.
6.Components must not remain uncapped for
longer than 15 minutes. In the event of delay, the
caps must be fitted.
7.Receiver/driers must never be left uncapped as
they contain Silica Gel crystals which will absorb
moisture from the atmosphere. A receiver/ drier
left uncapped must not be used, fit a new unit.
8.The compressor shaft must not be rotated until
the system is entirely assembled and contains a
charge of refrigerant.
9.A new compressor contains an initial charge of
refrigerant oil. The compressor also contains a
holding charge of gas when received which
should be retained by leaving the seals in place
until the pipes are re-connected.
10.The receiver/drier should be the last component
connected to the system to ensure optimum
dehydration and maximum moisture protection of
the system.

AIR CONDITIONING
7
ADJUSTMENT 11.All precautions must be taken to prevent
damage to fittings and connections. Slight
damage could cause a leak with the high
pressures used in the system.
12.Always use two wrenches of the correct size,
one on each fitting when releasing and
tightening refrigeration unions.
13.Joints and 'O' rings should be coated with
refrigeration oil to aid correct seating. Fittings
which are not lubricated with refrigerant oil are
almost certain to leak.
14.All lines must be free of kinks. The efficiency of
the system is reduced by a single kink or
restriction.
15.Flexible hoses should not be bent to a radius
less than 90mm radius.
16.Flexible hoses should not be within 100mm of
the exhaust manifold.
17.Completed assemblies must be checked for
refrigeration lines touching metal panels. Any
direct contact of lines and panels transmits noise
and must be eliminated.PERIODIC MAINTENANCE
Routine servicing, apart from visual checks, is not
necessary. The visual inspections are as follows:
Condenser
With a water hose or air line, clean the fins of the
condenser to remove flies, leaves, etc. Check the pipe
connections for signs of oil leakage.
Compressor
Check pipe connections for signs of oil leakage.
Check flexible hoses for swelling. Examine the
compressor belt for tightness and condition.
Sight glass
Examine the sight glass for bubbles with the system
operating. Check connections for leakage.
Evaporator
Examine the refrigeration connections at the unit.

AIR CONDITIONING
1
REPAIR COMPRESSOR
Service repair no - 82.10.20
Remove
1.Disconnect battery.
2.Recover refrigerant from air conditioning system
See Adjustment, Refrigerant recovery,
recycling, recharging.
3.Remove compressor drive belt.See
Compressor drive belt
4.Disconnect high pressure pipe from compressor.
5.Disconnect low pressure pipe from compressor.
6.Remove 'O' ring from each flange.
7.Disconnect compressor clutch harness
multi-plug.
8.Remove compressor from mounting bracket
studs.Refit
9.If a new compressor is to be fitted first drain oil
from new compressor. Drain and measure oil
from old compressor. Measure new oil equal to
amount from old compressor, add 30 ml extra to
this amount and refill new compressor through
outlet port.
10.Locate compressor over mounting bracket studs.
11.Reconnect compressor clutch harness
multi-plug.
12.Fit new 'O' rings to high and low pressure hose
flanges, lubricate with refrigerant oil.
13.Fit high and low pressure hoses.
14.Fit compressor drive belt
See Compressor
drive belt.
15.Evacuate and recharge air conditioning system
See Adjustment, Refrigerant recovery,
recycling, recharging.
16.Reconnect battery.
17.Perform a leak test on disturbed joints.
18.Carry out a functional check.

82AIR CONDITIONING
4
REPAIR
8.Remove 4 bolts and large packing washers
securing fan cowling brackets to wing sides.
9.Remove 4 nuts securing fan cowling to lower
mounting bracket and lift complete assembly
from condenser.
10.Remove 2 bolts securing bonnet striker support
plate and cross braces to grille top panel.
11.Remove 2 bolts securing cross braces to front
wings.
12.Lift condenser, from bottom mounting lugs and
carefully ease forwards to clear top grille panel.
13.Lift condenser, complete with receiver/drier, from
vehicle taking care to clear high and low
pressure hose/pipes at side of radiator.
14.Disconnect condenser and receiver/drier pipes.
15.Remove clamp bolts and release receiver/drier if
a new condenser is to be fitted.
16.Discard all pipe connection 'O' rings. Cap or plug
all connections to prevent ingress of dirt and
moisture.Refit
17.Coat unions, threads and new 'O' rings with
refrigerant oil prior to reassembly.
18.Secure receiver/drier to mounting clamps.
19.Fit condenser and receiver/drier pipes.
20.Lower condenser into position ensuring high and
low pressure pipes are located between radiator
and front wing.
21.Secure cross braces and bonnet striker support
plate to top grille.
22.Secure cross braces to front wings.
23.Secure fan cowl assembly to lower mounting
bracket and front wings.
24.Fit high pressure pipe at evaporator.
25.Fit condenser low pressure pipe at compressor.
26.Connect multi-plug at receiver/drier dual
pressure switch.
27.Connect fan motor lead multi-plug.
28.Evacuate and recharge air conditioning system
See Adjustment, Refrigerant recovery,
recycling, recharging.
29.Reconnect battery.
30.Fit grille panel.