Land Rover Defender V8i Workshop Supplement Rover Manual

26 - COOLING SYSTEM
CONTENTS
Page
DESCRIPTION AND OPERATION
ENGINE COOLING 1..............................................................................................
COOLANT CIRCULATION 2...................................................................................
FAULT DIAGNOSIS
ENGINE OVERHEATING 1....................................................................................
ENGINE RUNS COLD 2............................................................................................

COOLING SYSTEM
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 expansion tank. The coolant radiator also
incorporates a section at the side for cooling the
engine oil. The transmission fluid cooler is mounted
below the radiator.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...

26COOLING SYSTEM
2
DESCRIPTION AND OPERATION COOLANT CIRCULATION
Operation
When the engine is started from cold the thermostat
prevents any coolant circulation through the radiator
by closing off the top hose. During the engine warm
up period, the water pump, pumps coolant around the
cylinders to the rear of the cylinder block along the
main galleries in both cylinder banks. At the rear of
the cylinder block the coolant rises through a large
port in each cylinder head/block joint face, and then
flows...

COOLING SYSTEM
1
FAULT DIAGNOSIS ENGINE OVERHEATING
Before conducting any cooling system diagnosis:
See
Description and operation, Engine Cooling
1.Is coolant level correct?
NO - Allow engine to cool, top up level to
expansion tank seam.
YES - Continue.
2.Is coolant in radiator frozen?
YES - Slowly thaw and drain system.
See
Adjustment, Coolant Requirements
NO - Continue.
3.Is air flow through radiator restricted or blocked?
YES - Apply air pressure from engine side of
radiator to clear obstruction.
NO -...

26COOLING SYSTEM
2
FAULT DIAGNOSIS ENGINE RUNS COLD
Before conducting any cooling system diagnosis:
See
Description and operation, Engine cooling
1.Check operation of viscous unit.See
Description and operation, Viscous Fan
Is viscous unit operating correctly?
NO -
See Repair, Viscous coupling
YES - Continue.
2.Is thermostat correct type and operating?
See
Repair, Thermostat
If problem is not diagnosed: Continue.
3.Are the air conditioning fans operating
continuously?
YES -
See Electrical Trouble...

COOLING SYSTEM
1
ADJUSTMENT COOLANT REQUIREMENTS
Frost precautions and engine protection.
Cooling systemMUST ALWAYSbe filled and
topped-up with solution of water and anti-freeze,
winter and summer.NEVERuse water alone, this
may corrode aluminium alloy.
CAUTION: Do not use salt water otherwise
corrosion will occur. In certain territories
where only available natural water supply
has some salt content use only rain or distilled
water.
Recommended solutions
Anti-freeze:Universal anti-freeze or permanent...

26COOLING SYSTEM
2
ADJUSTMENT
NOTE: It is not possible to drain all coolant
retained in heater system.
7.Remove engine drain plugs beneath exhaust
manifolds and allow coolant to drain from
engine.
Refill
1.Fit drain plugs to engine.
2.Connect hose to coolant pump and secure with
clip.
3.Fit viscous coupling.
See Repair, viscous
coupling
4.Pour correct solution of water and anti-freeze
into expansion tank until radiator is full.
5.Start engine and run until normal operating
temperature is reached.
6.Top...

COOLING SYSTEM
1
REPAIR EXPANSION TANK
Service repair no - 26.15.01
Remove
WARNING: Do not remove expansion tank
filler cap when engine is hot. The cooling
system is pressurised and personal
scalding could result.
1.Remove expansion tank filler cap by slowly
turning it anti-clockwise. Pause to allow pressure
to escape then continue to turn in same direction
and remove.
2.Position container to collect any coolant spillage.
3.Loosen clip securing radiator hose to expansion
tank.
4.Release radiator hose...