The cooling system maintains engine temperature at an efficient level during all engine operating conditions. When the engine is cold the system cools slowly, or not at all, to allow the engine to warm up quickly.

The cooling system includes the following components:

Operation of the cooling system requires proper functioning of all components. Coolant is drawn from the radiator by the coolant pump and circulated through coolant jackets in the engine block, intake manifold, and cylinder head(s), and then directed back to the radiator where it is cooled.

This system directs some coolant though hoses to the heater core, to provide for heating and defrosting. A recovery reservoir is connected to the radiator to recover coolant displaced by expansion from high temperatures and maintain correct coolant level. As the coolant cools and contracts it is drawn back into the radiator by vacuum.

The coolant pump is belt driven. Coolant from the radiator outlet (lower right side of the radiator) flows to the coolant pump inlet and is pumped through coolant passages in the cylinder block and into the cavities surrounding the cylinder liners. Coolant flows through holes in the cylinder head gaskets into the cylinder head coolant passages and into the throttle body coolant system. Passages in the intake manifold direct the coolant to the thermostat at the rear of the manifold. When the thermostat is closed (cold engine), the coolant is prevented from retuning to the radiator and is recirculated for quick engine warm-up.

Once the engine has warmed sufficiently, the thermostat opens and coolant flows to the inlet tank on the top left side of the radiator. It is cooled as it flows across the horizontal core tubes to the outlet tanks on the right side of the radiator, completing the cycle.

This switch activates a warning lamp in the Instrument Panel Cluster if the engine overheats. With optional instrumentation, a temperature gauge replaces the warning lamp and a transducer replaces the temperature switch. For location and diagnosis of the switch, refer to Temperature Lamp Switch in Electrical Diagnosis.

The fan and the clutch mount to the water pump. The clutch has a heat sensitive spring that contracts as the engine temperature changes. This factor determines how fast the fan blades turn in order to cool the radiator.

The coolant pump is a centrifugal-type pump consisting of an impeller, impeller drive shaft, pulley flange, and a cast housing. The pulley which attaches to the pump is driven by the accessory drive belt.

You can use various methods and equipment to flush the cooling system. If special equipment is used (such as a back flusher) follow the manufacturer's instructions. However, always remove the thermostat before flushing the system.