Clutch Fan vs. Flex Fan

[Mikey]

Typical thing.....Bronco is running pretty warm but not over-boil...especially at idle in summer at 5000 ft. Stock 302 with C4.

If I had the stock flex fan or a stock Ford clutch fan, what's better for cooling? Any other considerations?

Thanks,
Mikey

 

[76 explorer]

i dont think you can run a clutch fan without moving the radiator forward. at least that was the case for my 76

ive found fixed pitch blades to work the best.

 

[SaddleUp]

Clutch fans works better for cooling at slow speeds. You might not be able to fit one in though.

 

[Mikey]

Thanks! I've got a 79 Ford van with a 302 and C6 I'm parting out and it has a clutch fan. Having a bit of warm idles so was going to break out the tape measure and see if I could fit it if you guys thought it might cool better than the stock 74 flex fan. If not, maybe I should track down a good aftermarket flex fan?
Thanks again,
Mikey

 

[a67and77]

I just put a clutch fan set up on my 77 Bronco with the help of a friend of mine at A and D automotive with about 1 inch between the clutch and plenty of fan space from a 4 core radiator in stock location. The temp here has been hot around 96-100 or so depending where your at. My temp won't go over 195 right now with a 180 thermostat. I got the parts from Napa and can get the part numbers from my friend that ordered them. It's a real stubby thermostatic clutch assembly and a fixed pitch fan. So far works great...

 

[RT]

I put in a clutch fan (fixed pitch fan) about two years ago , so far so good.

I found the stubby after I moved the rad ahead , so now I have more than enough room. But I had to extend my shroud about a inch.

This setup is way quieter on the freeway too.

 

[DonsBolt]

a67and77 and RT

Can you share your setups with us. Part numbers and any other info you can give us.

I would love to run a clutch fan, it would be quieter, maybee free up a few HP(especially at higher rpms) give a little better fuel millage, and would be much better if you ever cross rivers or streams

 

[73stallion]

most auto part stores do have a listing for a fan clutch for the EB's, but as stated above i don't think you'll have enough room. i don't in mine, otherwise i'd have one.

 

[a67and77]

As soon as I get the NAPA part numbers I'll send them to who needs them. It was a trial and error experience. My buddy went through a number of fan assemblies untill he found the right one to use and then helped me out with it. His 76 ran much cooler than mine for some reason with this setup. I went through a couple of clutches until he orded me this stubby one and have enough room to run a 4 core, stock fan shroud, and all is in the stock location. My engine runs much quieter. I hope it continues to work out for me. I ran a flex fan with no luck, stock fan with better luck but heavy, and now the setup I run now thanks to Danny at A and D.

 

[Mikey]

You guys are right, it does not look like the 79 Van clutch fan will fit. It looks about 1/4" too long. Any ideas how I could fit it? Is it possible to remove the clutch from my stock clutch fan and install the shorter clutch?

Ideas? I'd like to get off cheap since I have the 79 Van's clutch fan.
Thanks,
Mike

 

[73stallion]

As soon as I get the NAPA part numbers I'll send them to who needs them. It was a trial and error experience. My buddy went through a number of fan assemblies untill he found the right one to use and then helped me out with it. His 76 ran much cooler than mine for some reason with this setup. I went through a couple of clutches until he orded me this stubby one and have enough room to run a 4 core, stock fan shroud, and all is in the stock location. My engine runs much quieter. I hope it continues to work out for me. I ran a flex fan with no luck, stock fan with better luck but heavy, and now the setup I run now thanks to Danny at A and D.

i want that part number for sure!

 

[Mikey]

...part numbers and price estimates....

 

[BroncoDad]

As soon as I get the NAPA part numbers I'll send them to who needs them.

I'd be interested in those numbers as well! Thanks!

 

[RT]

I looked through the Hayden web page thinking I would recognize the numbers,,,oooffff,, Toooo many numbers
http://www.haydenauto.com/assets/2005Haydencat.pdf

But I happened to find the boxes in the workshop !!!!!

The clutch I used first is Hayden part # 2711 but the 2710 is a little shorter, this might be the one a67and77 used.

The fan I used is Flexalite's 18" clutch fan Pt # 5718.

Good luck guys,

 

[Mikey]

I wonder if the clutch would fit onto a stock clutch fan? Are the fan mounting holes pretty standard?

I don't live near a NAPA. Any idea where I could mail order?

Thanks,
Mikey

 

[VT_Don]

fan clutches

This has been addressed a few times. I have never seen any data varifiying parasitic loss of a fixed fan at highway cruise speed. But, will not argue the benefit of noise reduction.
My issue is, in low range at crawl speed, the only cooling effect is the fan. Having a fan that is less than direct drive, is questionable.
Personally, I have damaged (2) radiators when the bearing in a clutch fan got worn enough to let the blade wobble. Ever see a circle track or road race car with a clutch fan? Damn good reason why not!

 

[DonsBolt]

I looked through the Hayden web page thinking I would recognize the numbers,,,oooffff,, Toooo many numbers
http://www.haydenauto.com/assets/2005Haydencat.pdf

But I happened to find the boxes in the workshop !!!!!

The clutch I used first is Hayden part # 2711 but the 2710 is a little shorter, this might be the one a67and77 used.

The fan I used is Flexalite's 18" clutch fan Pt # 5718.

Good luck guys,

I did a little research and this might be a better part number for the clutch part

Hayden part # 2747 it looks to be the same dimensions as the 2710 but a heavy duty thermal instead of the standard thermal unit.

I have to do some more research but it might be a better unit.

 

[RT]

The fan bolt Dia is larger. 3.25" instead of 3". I remember trying to get a fan to fit the 2741 but they were too large of a over all diameter.(over 18") If the fan could be opened up at the center , and the bolt holes stretched a little it should work.
If you can't get a fan from flexalite maybe try getting a fan from a wrecker , if they can tell you what the application the 2747 is for.
I think I went this route and the fan was going to be too big. But it's been too long ago too remember.


Hope I remember the way to SOB

If you get the heavy duty one to work , let us know. I haven't had a issue with mine yet , but if I can overkill something , I'll do it. ;D

 

[Mikey]

Where can one order a Hayden clutch and roughly how much money?

 

[ElJefe]

This has been addressed a few times. I have never seen any data varifiying parasitic loss of a fixed fan at highway cruise speed. But, will not argue the benefit of noise reduction.
My issue is, in low range at crawl speed, the only cooling effect is the fan. Having a fan that is less than direct drive, is questionable.
Personally, I have damaged (2) radiators when the bearing in a clutch fan got worn enough to let the blade wobble. Ever see a circle track or road race car with a clutch fan? Damn good reason why not!

The beauty of a clutch fan is it lets you can run a MUCH more aggressive fan than you would be able to run if using a direct drive, and only tap into the reserve CFM when the engine temps require it. The clutch fan on my landcruiser sounds like a turbine for the first 4 or 5 seconds after startup until the fan clutch releases. Pulling enough air to feel it sucking 6 inches away from the grill at idle. My 76 with a direct drive fan can't come close to the CFM of the Cruiser with a clutch fan locked.