Well, I have all of the bolt on stuff, off of my motor right now. and i was going to replace my fan clutch. Here's my questions, -What's the difference between a thermal clutch and a non thermal clutch. (they offer both for my car) Also, I can't find a replacement fan like mine. It is an a/c fan for a 390 fe, with 7 blades. -Can I paint my existing fan or is this a bad idea? Thanks in advance for any info.
A non thermal clutch is on at idle and shuts off at higher rpm, or at least slips more. A thermal clutch has a thermostat in the center that is visible. When it gets hot, it restricts fluid flow and has more lock up. HD fan clutches make the fan howl when it reaches approximately 215 degrees. They really lock up. They also will turn off as they approach 180 to 190 degrees. Yes, you can paint your existing fan. I will also say that Hayden HD fan clutches only last about a year for me. I had to carry a spare in my truck and change them out on the road. I had this down to about a 20 minute process on a hot engine in the desert................
Use OEM thermals from junkyard...last forever. They are even crudely adjustable...unhook end of thermo spring, wrap tighter or looser and rehook. Run only when hot, stop and use zero ppower when not needed.
so you guys think whether i have a thermo clutch or not, i should run one? sorry man, this quote kind of lost me. Sorry to ask for further explanation, but I've never changed a fan clutch before. I've bolted on flex fans, but never had the privlege of pulling a clutch
The thermo clutch uncouples when cool enough and fan just freewheels, so no useless power drain when car is moving.
And the flex fans continue turning no matter what...you rarely actually need fan except when idling or moving very slowly.
Since the fan is in the radiator's airflow, it heats up as the airstream does. With a thermal clutch, at low temps the clutch is real slippy. At high temps it's pretty much locked up. There's actually a little heat sensitive spring on the front that's very similar to a carburetor choke spring, it moves with temp change and actuates the clutch "slippy lever" (technical term) With a non thermal clutch, it's medium slippy all the time so that fan blade RPM is connected to your engine RPM with a rubber band effect of always trying to catch up. make sense?
Thanks for the info guys, I appreciate everyone taking the time to clear that up for me. Wild Earp said I can paint my fan, this wont effect the fans balance in any way?
Heck yea. Paint that sucker. I allways paint mine black then mask the last 2 inches and paint them bright yellow. Kinda like a WW2 prop. Looks cool but still bites stupid fingers.
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