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Old 03-10-2007, 11:55 AM
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xntrik xntrik is offline
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Originally Posted by Classix_Lover
Ok, here's the deal. Got another fan clutch, heavy duty this time, Hayden brand.

, everything spun true and of course massive cooling improvement at higher speeds compared to the other mediocre electric fans.

Once again, let it idle for a good while. Shut it off and imediately grabbed the fan blades to spin it and whaddya knowwww! The damn thing is STILL freewheeling and not properly locking up.


First, you don't need a fan above 30 mph, so it shouldn't make any difference. If it made a difference it is probably because the electric fan was blocking the airflow.

Second, you don't know how hot the air is going across the fan clutch.,,,,,


Third, the fan clutch is so close to the radiator that air cannot flow across it readily, so it might not be working correctly. 1 1/2 inches minimum clearance is needed for airflow.

Fourth, you are probably going to have to use a Derale stainess flex fan with 2 1/2 inches pitch and make a shroud, since a factory shroud will be too long and not match to your blade position. The blade should only be 3/4 inch maximum into the shroud.

Actually I don't think you will need a shroud if you use a high pitch Derale fan blade 3/4 inch from the radiator. I didn't.

I can hold my hand 10 inches in front of the radiator and feel the air pulling in with the engine at idle. I have never had a problem at 100+* and idling with the AC on. No shroud.

Sorry I missed your picture earlier.......
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Last edited by xntrik; 03-10-2007 at 12:13 PM.
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