Jeep Fan Clutch: Controlling Radiator Fan Speed

Anthony Fontanelle
January 28, 2008

Engine overheating, particularly during summer, can get on the nerves of every motorist. When it happens, the vehicle apparently stops operating. That explains why all vehicles are equipped with various components such as the radiator to keep the engine cool. But a radiator is not all that is needed. For off-road vehicles like Jeep, radiators need assistance in keeping the engine’s ideal temperature. The radiator fan and Jeep fan clutch work together to help the radiator do its task.

Radiator fans need to operate at an appropriate time and speed. Controlling the speed of the radiator fan is what the Jeep fan clutch does best. This radiator component is a small fluid coupling designed to be sensitive to temperature changes. The small fluid mixture in the fan clutch is composed partly of silicone oil. The Jeep fan clutch lets out this silicone oil through the bimetal coil spring and into the fluid coupling. However, this is only left to flow out when the temperature of the air passing through the radiator is high. The fan clutch then causes the bimetal coil spring to open up to let the oil flow out into the fluid coupling. Afterwards, the radiator fan starts to rotate at the appropriate speed. If the air’s temperature is already cool, then the oil goes back to the fluid coupling, making the fan run slowly.

The Jeep fan clutch can be found near the water pump. A belt and pulley attached to the crankshaft make the fan clutch work. The fan clutch is equipped with a thermostatic device that controls the rotating fan’s speed to match the temperature in the engine, preventing it from overheating. When the radiator fan is not needed, the fan clutch can make it slow down. That way, fuel consumption is reduced and engine power is conserved.

Source:  Amazines.com