Chevrolet Repair: radiator fan cluch, fan clutches, fan clutch

Question
how do i know if it bad? is it hard to replace? this is on a chev. 350 v8 and i think it is a 1990

Answer
Hello Ken,
You could Google search for testing fan clutches, and get a ton of information, but basically, with the engine off and cold, you should be able to easily turn the fan blade, but it shouldn't just continue to spin freely.
There shouldn't be a great deal of play where the clutch mounts to its shaft, if you move the blade front to rear, but a tiny bit is acceptable, as long as fluid, or oil, is not leaking out of the hub/shaft seal area.
The clutch should definately NOT be locked up solid.
And...after warming up the engine, when you turn the engine off, the fan blades should not continue to free wheel. When hot, it should stop within probably one revolution of the engine stopping.

One thing that points toward needing a fan clutch is if the engine runs hot in city traffic where you are stopped often, but cools down when driving on the highway. That indicates that the fan is not moving enough air through the radiator to dissipate the heat.

Van