How to test fan clutch operation?

[CyFi6]

I have looked in the TSRM, and the only thing it mentions about the fluid coupling fan clutch is that it should not have any signs of leaking. Now, i don't see any signs of leaking on mine, but is there a way to functionally test the fan clutch? I am going to be moving to an area with very warm temperatures and i want to make sure my cooling system is up to par! I have a good fan shroud, new radiator, and fresh mix of coolant in it right now with a new head gasket. Thanks very much for any help!

 

[natedogr]

i think you just try to turn it, while the car is off obviously, and if theres some resistance to it then its in good condition. if it spins freely then you should replace it. i've read that on sf before and someone just mentioned that in a recent thread today i believe.

 

[jetjock]

Indications of a working clutch:

1) Clutch should have resistance to turning. It should stop in less than one rev when spun hard when cold.

2) It should engage when the engine is started and then smoothly quiet down as the rpm is brought up to 2000 and held there. If you're under florescent lights you'll be able to see this happen. A timing light can also be used.

Testing:

1) Insert longish temperature probe between radiator and shroud so as to measure temp ear clutch bimetallic coil.

2) With engine at hot idle block airflow through radiator.

3) Clutch should begin to engage at about 170 F and be fully engaged by 200 F.

4) Unblock radiator. Clutch should be begin to disengage at about 190 F and be fully disengaged by 165 F.

If it doesn't work (and assuming the bearing is still good) split the case and refill with 50cc of 3000 centistoke silicone oil from the local hobby shop or buy a new one....

 

[CyFi6]

Wow thank you guys, just the information i needed!