How To Upgrade 302 to a Thermostatic Clutch Fan

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1971 Mach 1
Thought I would get this out here since it is a pretty easy upgrade and only takes about 20 minutes. The direct drive fan works great for cooling but isn't exactly performance friendly. Upgrading to a modern thermostatic clutch fan will net a few easy horsepower and quiet down the engine a little bit also.

Also it gets the fan a little further into the shroud which IMO makes it less of a danger to fingers working in the engine bay. Direct drive fans hurt......

Parts I used are below.

Derale 17" 6 Blade Fan #17117

http://www.summitracing.com/parts/der-17117

Hayden Fan Clutch #2710

http://www.summitracing.com/parts/hda-2710

4 Fine Thread 5/16x1" Bolts to bolt the clutch to the water pump

4 Course Thread 5/16x3/4" Bolts to bolt the fan to the clutch

8 5/16 Lock Washers

Installation is easy take off the old fan and spacer. Bolt the new fan to the clutch paying attention to which is front and back. The fan will be labeled either saying what side is front or what side faces the engine. A bushing is included with the hayden fan clutch the needs to be installed to center the clutch properly on the water pump. Slide the new fan setup into place and bolt it on. Below are pictures to show that the new fan setup sets just a smidge farther into the shroud but just about the 50/50 in and out which is generally considered the desired spot for a fan.

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Great information, I was wondering if you could dumb this down for me. How do these actually work? How does it sense when to turn on and turn off? Is there applications these are not good for? Is there good track records for these on use on high milage application?

 
A thermostatic fan works off of heat transfer from the water pump. As the coolant gets hotter the heat transfers to the water pump pulley and fan shaft. The hotter it gets the more it causes the fan to engage. This one primarily engaging at 170 degrees and progressing from that temp. This type of fan has been in use for many years on various engines from OEM Manufacturers(Ford, Chevy, Dodge). Ford chose not to install a clutch fan on the early 302's. Opting for the direct drive fan which has an affect not only on HP but also gas mileage. Because the motor is always forced to power the fan at full even when it isn't needed.

 
I added a clutch fan to my 351C also. Came off a 351M late 70s early 80s. Easy junk yard find. I think the clutch fan off the 80s Crown Vics and Grand Marquis will also work.

 
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