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Old 02-21-2006, 12:17 AM   #1
Green Machine
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Another clutch fan question ?

I have added a thermostat clutch fan to my 68 and my 88 has one stock. They both have the thermostat coil on front. When the engines are stone cold, even 10 below the fan turns until they warm up, this seems totally backward but they never over heat in hot weather either, Is the fluild just to stiff when cold or are my clutches damaged ???
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Old 02-21-2006, 09:52 AM   #2
Stocker
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Re: Another clutch fan question ?

Quote:
Originally Posted by Green Machine
Is the fluild just to stiff when cold
I suspect that's it. I've had many over the years (on different vehicles), and typically when you start driving, the clutch will be engaged briefly, then the roar will fade away as it disengages. Yours sound normal to me.
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Old 02-21-2006, 11:06 AM   #3
sneakysnake
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Re: Another clutch fan question ?

The fan will always be turning,but the temp will determine if it slips on the shaft.The warmer it gets the less it slips there for moving more air.
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Old 02-21-2006, 02:29 PM   #4
68speedalert
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Re: Another clutch fan question ?

The clutches have a fluid, usually silicon, the is stiff on start up. As the fan turns after starting, fluid warms and releases the clutch, causing the roar to subside.

They are both working as designed.
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Old 02-21-2006, 08:18 PM   #5
Stocker
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Re: Another clutch fan question ?

Quote:
Originally Posted by sneakysnake
The fan will always be turning,but the temp will determine if it slips on the shaft.
Yup. I oversimplify by stating it disengages. It slows to the point you can't hear the roar, and parasitic drag is greatly reduced.
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Old 02-21-2006, 08:29 PM   #6
Green Machine
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Re: Another clutch fan question ?

Thanks, I was thinking they are OK, never hurts to ask I guess. Electric would be nice, but these are so simple and easy.
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