big electric fan?

[LilRhodyXJ]

the other day i was getting a new breather hose for my front diff and the sales man at autozone was eyeballing my jeep...he said that people tear out the clutch fan and put in 18" electric fans wired to switches....now ive her dof this before but was wondering how well it worked..he said u take out the pulley the stock clutch fan is on and get a little less strain on the engine..and because of the switch u can actually keep it cooler...so has anyone done this and had good success if so was it easy and worth it?...ive read some of the posts but want to kno really how hard is it for one and what size fan should i put in there?

thanks
andrew

[dallas xjs]

thank god some 1 uped this one...i am waiting on a answer to..5-90....OT...any input on this...hp gains? etc

[muddshutter]

YES, yes, and YES......

I have two fan units on mine and it has made a world of difference. More HP gain, its quieter, i turn them on when i want to, there is a heat override, they are just wonderful. Try it, do it, its worth every penny.

[5-90]

If you pay attention, it can be worth it. I'd not bother to do it on my rigs at the moment, because I honestly don't need the nominal amount of torque that would be freed up by not having the engine drive the fan. Also, you may want to search around here - find out what works and what doesn't. You'll get good guidelines for fan selection - apparently, you need something like 2000cfm out of EACH fan in order to get good cooling (that number is from a spotty memory - but it is rather high, whatever it is. Probably 1800-2500cfm, with more being better.)

Also, plan your circuit fairly carefully - by the time you get into moving that much air, you're also going to be pushing quite a lot of electrons (one installation I'd seen using Derale fans had two fans with 40A ATC fuses for EACH fan!)

Is is possible? Yes. Is it desireable? Depends on what you're doing. I like the reliability of the mechanical fan, and I've got to get a prototype of my Fan Clutch Eliminator done one of these days (it would be easier if I had a CNC shop here, you know...)

Would I do it? Depends. I've been planning something like that for Project: REDSHIFT - but that's going to want every scrap of torque/power I can deliver to the rear wheels. For a regular combo-duty or street rig, I'd not bother. For a 'crawler, it does have its appeal - not so much for the power/torque you free up by not driving the fan anymore, but because of the consistent supply of forced air you'll have over the radiator to cool your engine.

One way or the other, you'll want to do some research before you start buying parts - find out what has worked for someone else and what hasn't. Probably two-thirds of the e-fan conversions I hear of around here go back to a mech. fan, simply due to bad e-fan selection (not moving enough air.)

5-90

[muddinxj04]

i've heard of guys putting ford taurus fans in...cheaper and flow more air...so i hear

[beakie]

a simple search will give lots of info on this topic.
I have a taurus fan in the garage that is too big to fit into the front of my rig. I could make it fit yes, but I don't have a controller to look after turning the fan on and off when the temps call for it. There are controllers out there, and my thought is to just use a simple switch in the cab I can use to turn the fan on and off... but if I lend my truck out and that person doesn't know about it, could cause problems for them... and more importantly me.
My aux fan is on a switch, and my engine runs very very cool, so I am not worried about overheating right now going into winter, but next summer if it runs this cold I may look into this mod as others have.
18" seems too large from what I have read, seems 16" is big too... I think 12" is what your looking for, even a good 10" fan will suffice if it moves enuf air.

[87manche]

Marcus has an excellent writeup on this, and it included Dino's bit about modifying the belt routing.
read it, be it.
http://go.jeep-xj.info/HowtoElectricFan.htm

[Dr. Dyno]

Here's my own write-up:

http://www.angelfire.com/my/fan/electric.html

The total airflow from the factory auxiliary electric fan plus the new electric fan should equal at least ten times the flywheel HP output of the engine i.e. 2000cfm on a 200hp engine, 3000cfm on a 300hp engine.
The higher the better, but remember that a bigger fan with a higher airflow will also draw more current from the battery. You may need to upgrade to a higher amperage alternator than the stock 90amp unit if the current draw is enough to drain the battery.

[badron]

E fan can be a lot lighter. Plus at low RPM can move more air hands down! At high RPM the stocker wins big time.
E-fans free up torque:
Yes, when off or when the engines RPMs are high. When both fans are moving the same amount of air. The ALT will load the engine to feed the E-fan almost the same as a belt driven fan. E=Mc2 thing.
Besides you can kill an E-fan on deep water crossing and keep all that shine stuff on your engine form getting water spotted.