Join Date: Aug 1998
Location: Waldorf Md. USA
Usually a good test of the clutch is to go for a ride and get the motor good and hot, stop and let it idle for a minute or so and then shut the motor off while someone watches the fan. It should come to a stop within a revolution or two when it is hot. If it spins free for a while before it stops, the clutch is probably bad. This is sort of a subjective test. If you have a known good fan to watch, use that as a comparison.
The fluid is some sort of silicon substance and I do not beleive it is servicable. Like mccorry said, a new one is cheap, I would just replace it if it is bad.
Advanced Automotive Machine