Hey guys, I changed out the fan clutch a while back and can't seem to get rid of a new roar created by the fan blade now. been through four different clutches. The original had no noticable noise at all. The original clutch was also a lot thinner than any thing I have found at any parts house.
The roar is so loud @ 3,000 rpm it is starting to dround out the exhaust (Momma"s not happy).
My fan blade seems to match what is being sold for stock for a 1972 350 ci. w/ac.
Thanks for any suggestions.
David

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Is it a thermostatic or a centrifugal clutch? A thermostatic clutch as a little coil spring steel in the center which engages the clutch when it gets hot. You can actually hear the difference when it engages. The centrifugal has nothing in the center and just gets tighter with higher rpm. Sounds like thats the one you have.

 

I've noticed that the seven blade fans on A/C cars do roar when the clutch engages. I kept my five blade when I installed A/C and never had any cooling problems or fan roar.

 

thermastatic clutch with 7 blade fan, noise is there even when cold though.
Any body tried the reproduction parts from corvette america, maybe thinner clutch more slip?
thanks

 

Just so I've got this straight, you kept the same seven blade fan that was quiet w/ the original (OEM) clutch and all subsequent clutches have caused fan roar when engaged (hot) or disengaged (cold)?

 

That is correct.
wierd huh?
Tried one from Napa, Carquest two from O'rlies.

 

Question to the forum guys; Would these after market clutches cause the fan to turn faster than the original clutch allowed, with less slippage than the original clutch permitted?
When I had the factory exhaust on my '81, my fan WOULD sound louder than the engine/exhaust at certain RPMs, however, not to the point of being annoying.
Please keep us posted.

 

Hey Texas Jim you may be on to something just got back from a drive and car was about15 deg. cooler than norm.
was running 195 now about 180. Its 94 outside.

 

Does it free wheel when cold, ie, doesn't roar when first started with a cold engine?

 

Roars just as loud cold as hot.
I drove about 3 hours today, thought it might need to be broken in. nothin changed. well... my blood pressure did go down a few points