2002 LAND ROVER DISCOVERY radiator cap

COOLING SYSTEM - V8
DESCRIPTION AND OPERATION 26-2-7
Inlet manifold - Cooling connections
Coolant leaves the cylinder block via an outlet pipe attached to the front of the air intake manifold. The pipe is
connected to the thermostat housing and the radiator by a branch hose off the radiator top hose.
Hot coolant from the engine is also directed from the inlet manifold via pipes and hoses into the heater matrix. Coolant
is circulated through the heater matrix at all times when the engine is running.
A further tapping from the inlet manifold supplies coolant to the throttle housing via a hose. The coolant circulates
through a plate attached to the bottom of the housing and is returned through a plastic bleed pipe to an expansion
tank. The hot coolant heats the air intake of the throttle housing preventing ice from forming.
An Engine Coolant Temperature (ECT) sensor is fitted in the inlet manifold adjacent to the manifold outlet pipe. The
sensor monitors coolant temperature emerging from the engine and sends signals to the ECM for engine
management and temperature gauge operation.

+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine
management.
Expansion tank
The expansion tank is located in the engine compartment. The tank is made from moulded plastic and attached to
brackets on the right hand inner wing. A maximum coolant when cold level is moulded onto the tank.
Excess coolant created by heat expansion is returned to the expansion tank from the radiator bleed pipe at the top of
the radiator. An outlet pipe is connected into the pump feed hose and replaces the coolant displaced by heat
expansion into the system when the engine is cool.
The expansion tank is fitted with a sealed pressure cap. The cap contains a pressure relief valve which opens to allow
excessive pressure and coolant to vent through the overflow pipe. The relief valve opens at a pressure of 1.4 bar (20
lbf.in
2) and above.
Heater matrix
The heater matrix is fitted in the heater assembly inside the passenger compartment. Two pipes pass through the
bulkhead into the engine compartment and provide coolant flow to and from the matrix. The pipes from the bulkhead
are connected to the matrix, sealed with 'O' rings and clamped with circular rings.
The matrix is constructed from aluminium with two end tanks interconnected with tubes. Aluminium fins are located
between the tubes and conduct heat away from the hot coolant flowing through the tubes. Air from the heater
assembly is warmed as it passes through the matrix fins. The warm air is then distributed into the passenger
compartment as required.

+ HEATING AND VENTILATION, DESCRIPTION AND OPERATION, Description.When the engine is
running, coolant from the engine is constantly circulated through the heater matrix.
Radiator
The 45 row radiator is located at the front of the vehicle. The cross-flow type radiator is manufactured from aluminium
with moulded plastic end tanks interconnected with tubes. Aluminium fins are located between the tubes and conduct
heat from the hot coolant flowing through the tubes, reducing the cooling temperature as it flows through the radiator.
Air intake from the front of the vehicle when moving carries heat away from the fins. When the vehicle is stationary,
the viscous fan draws air through the radiator fins to prevent the engine from overheating.
Two connections at the top of the radiator provide for the attachment of the top hose and bleed pipe. A connection at
the bottom of the radiator allows for the attachment of the bottom hose to the thermostat housing.
Two smaller radiators are located in front of the cooling radiator. The lower radiator provides cooling of the gearbox
oil and the upper radiator provides cooling for the engine oil.

+ MANUAL GEARBOX - R380, DESCRIPTION AND OPERATION, Description.

+ AUTOMATIC GEARBOX - ZF4HP22 - 24, DESCRIPTION AND OPERATION, Description.

+ ENGINE - V8, DESCRIPTION AND OPERATION, Description.

COOLING SYSTEM - V8
DESCRIPTION AND OPERATION 26-2-11
Viscous fan operation
A = Cold, B = Hot
1Drive plate
2Fan body
3Clearance
4Valve plate
5Valve
6Bi-metallic coil7Fluid seals
8Ball race
9Fluid chamber
10Reservoir
11Return port
When the engine is off and the fan is not rotating, the silicone fluid stabilises within the fluid chamber and the reservoir.
The fluid levels equalise due to the return port in the valve plate being open between the fluid chamber and the
reservoir. In this condition, when the engine is started, silicone fluid is present in the fluid chamber and causes drag
to occur between the drive plate and the body. This causes the fan to operate initially when the engine is started.
As the fan speed increases, centrifugal force and a scoop formed on the fluid chamber side of the valve plate, pushes
the silicone fluid through the return port in the valve plate into the reservoir. As the fluid chamber empties, the drag
between the drive plate and body is reduced, causing the drive plate to slip. This reduces the rotational speed of the
fan and allows it to 'freewheel'.
When the coolant temperature is low, the heat emitted from the radiator does not affect the bi-metallic coil. The valve
remains closed, preventing fluid escaping from the reservoir into the fluid chamber. In this condition the fan will
'freewheel' at a slow speed.

COOLING SYSTEM - V8
ADJUSTMENTS 26-2-13
ADJUST ME NTS
Drain and refill
$% 26.10.01
WARNING: Since injury such as scalding could
be caused by escaping steam or coolant, do not
remove the filler cap from the coolant expansion
tank while the system is hot.
Drain
1.Visually check engine and cooling system for
signs of coolant leaks.
2.Examine hoses for signs of cracking, distortion
and security of connections.
3.Position drain tray to collect coolant.
4.Remove expansion tank filler cap.
LH side
RH side5.Remove drain plugs from LH and RH sides of
cylinder block and allow cooling system to
drain.
6.Disconnect bottom hose from radiator and
allow cooling system to drain.
7.Disconnect top hose from thermostat and
position open end of hose below level of
coolant pump inlet, to allow coolant to drain
from the system.
Refill
1.Flush system with water under low pressure.
Do not use water under high pressure as it
could damage the radiator.
2.Apply Loctite 577 to cylinder block drain
plugs.Fit drain plugs to cylinder block and
tighten to 30 Nm (22 lbf.ft).
3.Connect bottom hose to radiator and top hose
to thermostat housing. Secure with hose clips.
4.Prepare coolant to required concentration.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Anti-Freeze Concentration.

COOLING SYSTEM - V8
REPAIRS 26-2-17
16.Remove radiator assembly.
17.Release clip and remove bottom hose from
radiator.
18.Remove 2 bolts and remove extension
brackets from radiator.
19.Remove 2 captive nuts from radiator.
20.Remove 2 screws and remove gearbox oil
cooler from radiator.
21. If fitted: Remove 2 screws and remove engine
oil cooler from radiator.
22.Remove 2 rubber mountings from radiator.
23.Remove sealing strip from bottom of radiator.
24.Remove 2 cowl retaining clips from radiator. Refit
1.Fit cowl retaining clips to radiator.
2.Fit sealing strip to radiator.
3.Fit rubber mountings to radiator.
4.Fit gearbox oil cooler to radiator and secure
with screws.
5. If fitted: Fit engine oil cooler to radiator and
secure with screws.
6.Fit captive nuts to radiator.
7.Fit extension brackets to radiator and secure
with bolts.
8.Fit bottom hose to radiator and secure with clip.
9.Fit radiator and engage lower mountings in
chassis.
10.Ensure connections are clean, then secure
hoses to oil coolers.
11.Fit air conditioning condenser brackets and
secure with screws.
12.Fit radiator upper mounting brackets and
secure with bolts.
13.Fit LH horn and secure with nut.
14.Fit air deflectors and secure with scrivets.
15.Connect multiplug of gearbox oil temperature
sensor.
16.Fit front grille.

+ EXTERIOR FITTINGS, REPAIRS,
Grille - front - up to 03MY.
17.Connect bottom hose to thermostat housing
and secure with clip.
18.Connect top hose to radiator and secure with
clip.
19.Connect bleed hose to radiator and fit clip.
20.Fit lower fan cowl and secure with screws.
21.Fit viscous fan.

+ COOLING SYSTEM - V8, REPAIRS,
Fan - viscous.
22.Top up gearbox oil.
23.Top up engine oil.
24.Refill cooling system.

+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.

AIR CONDITIONING
REPAIRS 82-35
18.Remove sealing strip from outer upper seam of
condenser.
19.Remove captive nut plates from condenser.
Refit
1.Fit captive nut plates to new condenser.
2.Fit seal to condenser.
3.Fit RH mounting bracket to condenser and
secure with bolt.
4.Fit receiver drier bracket assembly and secure
with bolts.
5.Ensure condenser pipe and new receiver drier
connections are clean.
6.Lubricate new 'O' ring with refrigerant oil and fit
to condenser pipe.
7.Fit receiver drier to bracket and condenser
pipe. Tighten bolt securing condenser pipe to 5
Nm (3.7 lbf.ft). Fit clamping bolt securing
receiver drier to bracket and tighten to 5 Nm
(3.7 lbf.ft).
8.Ensure adaptor block and receiver drier
connections are clean.
9.Lubricate new 'O' ring with refrigerant oil and fit
to adaptor block.
10.Fit adaptor block to receiver drier and tighten
bolt to 5 Nm. (3.7 lbf.ft).
11.Fit condenser assembly. 12.Fit cooling fan to condenser and fit bolts to
secure support rails to condenser brackets.
13.Ensure connections of condenser, receiver
drier and evaporator pipes are clean.
14.Lubricate new 'O' ring seals with refrigerant oil
and fit one seal to each evaporator pipe.
15.Connect evaporator pipes and tighten bolts to 5
Nm (3.7 lbf.ft).
16.Connect multiplug to dual pressure switch.
17.Fit radiator.
l

+ COOLING SYSTEM - Td5,
REPAIRS, Radiator.
l

+ COOLING SYSTEM - V8,
REPAIRS, Radiator.
18.Recharge A/C system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.