General

COOLING SYSTEM – V8

26-2-8

DESCRIPTION AND OPERATION

Description 

General 
The cooling system employed is the bypass type, which allows coolant to circulate around the engine and the heater 
circuit while the thermostat is closed. The primary function of the cooling system is to maintain the engine within an 
optimum temperature range under changing ambient and engine operating conditions. Secondary functions are to 
provide heating for the passenger compartment and cooling for the transmission fluid. The cooling system comprises:

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Radiator

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Passenger compartment heater matrix

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Transmission fluid cooler

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Coolant pump

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Thermostat 

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Expansion tank

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Viscous cooling fan

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Electric cooling fan

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Connecting hoses and pipes

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Fuel Burning Heater (FBH) – selected markets only

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Liquid cooled alternator housing.

The coolant is circulated by a centrifugal type pump mounted on the front of the engine and driven by an ancillary 
drive 'polyvee' belt. The coolant pump circulates coolant through the cylinder block and the cylinder heads via a 
chamber located in the 'vee' of the engine. Having passed through the engine, the coolant returns via a rear-mounted 
manifold that features the connections for the heater matrix and through pipes running in the 'vee' of the engine to the 
coolant pump. The coolant pump also circulates coolant to the radiator-mounted transmission fluid cooler and the 
liquid cooled alternator housing via flexible hoses. 

The die-cast coolant pump, driven by an ancillary drive belt, is fitted to the timing case cover. It contains the dual 
coolant temperature sensor and the electrically heated 'map controlled' thermostat controlled by the engine 
management system.

The map controlled thermostat incorporates a heating element inside a conventional expanding wax thermostat core 
which enables the engine management system to 'power' the thermostat open when the engine is under full load and/
or high output conditions. This provides sufficient cooling reserve through anticipation of the thermal load whilst 
allowing the engine to run at higher operating temperatures under part load conditions.
 

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 ENGINE MANAGEMENT SYSTEM – V8, DESCRIPTION AND OPERATION, Bosch ME 7.2 Engine 

Management System.

The radiator is a cross flow type with an aluminium matrix and has a drain tap on the lower left hand rear face. The 
bottom of the radiator is located in rubber bushes supported by plastic brackets which are clipped into the body 
longitudinals. The top of the radiator is located in rubber bushes secured by brackets fitted to the bonnet locking 
platform.

The radiator top and bottom hoses are connected to the outlet and inlet sides of the coolant pump housing 
respectively.

An expansion tank is fitted forward of the LH suspension turret in the engine compartment. The expansion tank allows 
for expansion of the coolant when the engine is hot and replaces the coolant into the system as the engine cools down.

The liquid cooled transmission fluid cooler is mounted on the plastic radiator support adjacent to the lower right hand 
rear of the matrix and receives coolant from either the bottom of the radiator or the return elbow pipe between the 
coolant pump and the radiator as required.

The Fuel Burning Heater (FBH) is located below the battery. The unit is connected in series with the coolant supply 
to the heater matrix.
 

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 AIR CONDITIONING, DESCRIPTION AND OPERATION, Description.

For additional airflow through the radiator matrix, particularly when the vehicle is stationary, two cooling fans are fitted; 
one being driven by the engine via the coolant pump drive shaft and one being driven by an integral electric motor.

CAUTION: The fan is attached to a threaded spigot on the pulley with a left hand thread.