Fan clutch Test?

[Aus94Q45]

Is there a reliable and easy way to tell if the fan clutch is operating properly?

[ardvarkus]

You're referring to the viscous coupling?

I'd never found any specs.

Wound up taking a 'known good' fan and comparing the time it took for a given weight to turn the clutch a given distance- measured at three different temps.

Adam

[Aus94Q45]

That is the one. I was hoping that there was some type of test you can preform on the car. Timing light marker or something. It is just difficult to tell if the thing is engaging like it should as I rev the engine. Thanks!

[ardvarkus]

It is surprisingly flat, at least to the human hand! The coupling when cool versus warm doesn't *seem* all that different, and at both temps it seems pretty loose.

The key is that at 3000 RPM there is still plenty of coupling to pull air.

My fault, BTW, was in the aux radiator fan- it had failed, and I didn't realize it. I wasn't getting adequate cooling and suspected the coupling.. finally found the mad fan motor, popped it out- new one in and it was fine.

A