Cooling System: Description and Operation

Cooling System
The engine has a closed liquid cooling system.

The cooling system consists of an inner and outer circuit. The outer circuit includes the radiator and expansion tank. The inner circuit contains the other components of the system and the heating system.

Circulation is controlled by a centrifugal pump, the rear faces of which are integral with the engine block. The pump is driven by the timing belt ensuring a uniform load on the pump bearings.

The system is filled and topped up through the expansion tank.

The only coolant covered by Volvo warranties is Volvo genuine coolant diluted 50/50 with pure water. This mixture helps prevent corrosion and freezing, and raises the boiling point to about 135°C (275°F).

Coolant need normally not be replaced unless the cooling system has been drained, during repair for example.

NOTE: the engine block is not fitted with frost plugs.