On models with air conditioning, the condenser is mounted in front of the radiator. All models have a separate expansion tank. The cooling system thermostat is located in the water pump housing on 4-cylinder models, or at the inlet on the left side of the cylinder block on 5-cylinder models.
The system works as follows. When the engine is cold, the thermostat is closed and the water pump pumps water through the internal passages, then through the bypass hose and heater circuit, through the thermostat capsule, and back to the water pump inlet. This water cycle cools the cylinder passages, combustion surfaces, and valve seats. However, when the coolant reaches a certain temperature, the thermostat begins to open. The coolant is now fed through the upper hose to the top of the radiator. As it passes through the radiator, the water is cooled by the air flow as the car moves, aided if necessary by the action of the electric cooling fan. Finally, the coolant returns to the water pump through the lower hose and the open thermostat.
The electric cooling fan is controlled by a thermal switch located at the base of the radiator. Additionally, on some 4-cylinder fuel-injected engines, a thermal switch is located near the injectors in the cylinder head. The water temperature is checked by a sensor in the cylinder head.
Warning: The electric cooling fan may operate even if the ignition is off when the radiator coolant temperature (and the cylinder head on some models) reaches a certain value. Therefore, exercise extreme caution when working near the fan blades.
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