E fan question

What CFM does a stock Fhead radiator need? I have a 900cfm fan that i am thinking about using and wanted to know if that is enough. the stock setup works fine but it would be nice to have the ability to turn it off for water crossing.

Tommy

 

not sure of cfm my fan is, i just got the biggest one that i could fit. had to go pusher thou.....

 

mine is not quiet the size of the stock fan. later model jeeps need like 1500CFM that is why i was wondering. did the earlier need less.

Tommy

 

any one else know the CFM? are e-fans not a good swap for this motor/radiator?

Tommy

 

I thought about putting one on mine to . Im not sure what CFM but I figured Id do like the race car , Put the biggest one that will fit on the rad. I think it would make a good upgrade for the little Hurricane and might free up a spare pony or 2 too

 

I was thinking about putting an E-fan on my CJ5 as well. Until I watched a buddy of mine with an 84 CJ7 put one on his rig.

He bought an aftermarket model that comes with "everything you need". Except had a heck of a time getting the sending unit dialed in, it would overheat 3 out of 5 times when he drove it, and it seemed like he was always having problems with either fuses or relays popping.

The only positive side that I could see was that it made the engine compartment a little quieter and you have the option of turning it off for water crossings, which he never did anyway... YMMV

If you don't want to go for a costly aftermarket unit, the early model Ford Taurus used an electric fan. You can usually get them from the wrecking yards with mounting plates and shroud for less that $50.

 

I have heard that the Taurus fans pull 90 amps at start up. Is this true?

Karl

 

I can tell you that when the fan on our old taurus would kick in you would know it, the lights would dim for a sec and all that fun stuff. I thought of going that route but decided to go another direction.

 

Why Electric?

Cause i have one sitting around and thought it might work.

Tommy

 

I can’t say what you’d need for your f-head motor but I’ll describe what I’ve got.
I’m using a Flex-lite 16” electric that moves 1600-1800 CFM attached to an aluminum 3 row radiator to cool a Corvette 327. I’m also using their adjustable thermostat and an automotive relay (20 A switched, 30 A constant) to power the fan.
I’m very happy with this set up. Hasn’t overheated once even when idling around back in the woods in the middle of July and August, when I couldn’t even just stand around and not pour sweat.
What I like ‘bout an electric fan is it’s moving the same amount of air no matter what the engine RPM’s are, can’t say that for a mechanical fan.
If you guys want to know more ‘bout the Taurus Fan set up, several of the guys at Jeeps Unlimited CJ Tech Forum are running it. Check their archives and if you don’t find what you want to know, just ask. Most of the members there are pretty helpful guys.

http://65.42.106.152/forums/forumdisplay.php?f=36

 

I run a Flex-A-Lite 120 fan. It was the only one I found to be slim enough to fit between the radiator and the water pump. It flows 1250 CFM and it seems to keep the engine right at 195 degrees which is what my thermostat is. The stock fan kept it at 180 all day long no matter what. I wired it to run manually with the flip of a switch, to run automatically with the included adjustable thermostat and also to be shut off manually for water crossings. It works great and draws 9 amps I believe. I found the included nylon mounting starps to be weak so I replaced them with small stainless teel threaded rod and stainless nuts passing thru the radiator. I also mounted the fan so the bottom of it's housing rested on the bottom lip of my radiator to help support it. I bought the fan from Summit for I think $105.00. It looks like there is room for a bigger diameter fan though. My blades are 12" and the entire unit is I think 13"x13".