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Fan Vs Fan???

kenny811

NAXJA Forum User
Location
Damascus, OR
I just installed a new 4,0 and in doing all this when it comes to the fans I have 2 options. I can go mechanical / electric, or I can run for about $105 2 electrical both switched anyway I want. Pros & cons of Fan setup's?? Alot guys have opinions on this, so I would like to hear some.

Thanks
Kenny
 
As long as between your fans you flow at least 3800CFM or more then you should be good. As, from my understanding.. stock e-fan pulls about 1800cfm and the mech fan is SUPPOSED to pull around 2kCFM. More flow the better.
 
E-fans win for low RPM and high stress. The mec fan just don't have the RPMs to pull lots of air at low RPM. Were as E-fans don't give a shit about engine RPM. They CAN also be lighter over all.
Bad side, E-fan can place an extra load on what many consider a marginal charging system as is, Add in a big amp and tons 150 watt lights that some people must have to off at (((5))) MPH. All this at low RPM when the alt is putting out min amps and you can see the problem coming.
A high out put alt MAY fix this problem.

The mec fan don't put a load on the alt. At higher RPM it will pull tons of air. Can be replaced at any auto parts store.
Down side, Has eaten more then one rad when the motor mounts go bad. Poor out put at lower RPM. May use a few more HP then a E-fan AT very high RPM,
You pick
 
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What about running 3 10" E fans? http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRM%2D19120&N=700+4294838842+400006+115&autoview=sku 2350 cfm each thats 7050 cmf total and 7 amps each so 21 amps. I would hook 2 up to a thermostat unit so your only pullen 14 amps getting 4700 cfm. Then if you ever are running warm it would most likly be in the hot day when your not using youir lights you can turn on the 3rd fan with a switch to bring down the temp. Would run about 220. bucks. Only thing is I dont know how loud these fans are.
 
I have been messing around with fans on my jeep for about a year now and finaly put the stock mech fan back on with a new 12" electric fan next to it, and I put another 10" out side the radiator blowing in. Everthing seems to stay cool for now have to give it a good test when it is hot out.
 
What about running 3 10" E fans? http://store.summitracing.com/partd...9120&N=700+4294838842+400006+115&autoview=sku 2350 cfm each thats 7050 cmf total and 7 amps each so 21 amps. I would hook 2 up to a thermostat unit so your only pullen 14 amps getting 4700 cfm. Then if you ever are running warm it would most likly be in the hot day when your not using youir lights you can turn on the 3rd fan with a switch to bring down the temp. Would run about 220. bucks. Only thing is I dont know how loud these fans are.

i see these on ebay all the time, similair except for the cfm's.

http://cgi.ebay.com/ebaymotors/JEEP...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
 
Wow that is a lot less cfm only 1100 cfm per fan 3300 total, you can get more then that with 2 of the other fans from summit racing 4700 cfm for cheaper. I havent got around to ordering them up yet I spent to much money on the jeep latley! But when I do ill post up the results.
 
If something goes wonky, and your fans burn out, you'll be up shit creek.


:wave1:

Yea! I agree with you totally;.... that includes about 90% of the vehicles sold in the US in the last 10+ years.

:huh: :doh:
 
:wave1:

Yea! I agree with you totally;.... that includes about 90% of the vehicles sold in the US in the last 10+ years.

:huh: :doh:

Your point?

If you're using and abusing your XJ in the middle of the woods and ford through a creek, and it shorts out your fans, your SOL.

Not exactly the same as a car that always sees pavement.
 
I recommend using the stock clutchfan. It's always gonna be spinning, and less chance of failure. If you're gonna do electrics make sure they flow more than the clutch fan, or else its not an upgrade. Electric fans do not work well underwater, and this is really what has kept me from installing one.
 
The cluthes on the clutch fans do fail, and most people do not notice that its the problem before they try everything else first, thats why they sell replacements. If I was going underwater lol Ya I would stick with the clutch fan. Ill keep my boat for that! The 2 electric fans would produce more cfm then the stock setup, When you are at low speeds climbing the clutch fan does not spin that fast untill you have high RPMs going. For the kind of wheeling that I do electric fan setup would be ideal. Here in Ca. there are not to many trails with water crossings. I guess theres a ideal setup for each kind of wheeler.
 
The mechanical clutch fan will hold up better than an electric fan if you're concerned about water being splashed onto it and shorting it out. But if there is a chance you will be going into deep water, an electric fan with a manual override is a better solution. Once the mechanical fan is submerged, it will most likely pull off of the shaft and into your radiator (destroying your radiator in the process), and then you're really screwed. Despite that disadvantage, I think my mechanical fan cools plenty well even at idle/crawling speeds, but then again the pre-91s had a closed loop cooling system which I've read to be more efficient.

I believe the most likely failure mode for the fan clutch is to be stuck engaged, so the fan will spin all the time and not slip at higher RPMs, causing your XJ to sound like a jet engine. I haven't heard of a clutch failing "open," where the fan won't spin at all.

If anyone is having major overheating issues, I would be looking at a bad thermostat or other cooling system issue, and do a drain/flush/refill before changing the fan setup.

So, to the OP, I would say go with the stock mechanical/electric setup, unless you were having specific issues to lead you away from the mechanical clutch setup.
 
I've done significant research on this as I have had several configurations in my heep. If you go electric, do yourself a big favor and spend the money on GOOD fans such as Spal. I have had several Hayden fans fail on me and I wouldn't buy their product again. The stock engine driven fan will pull the most air but it is loud. If you use a flex blade engine driven fan without a clutch you will get the best airflow at the cost of lots of noise.
 
I recommend using the stock clutchfan. It's always gonna be spinning, and less chance of failure. If you're gonna do electrics make sure they flow more than the clutch fan, or else its not an upgrade. Electric fans do not work well underwater, and this is really what has kept me from installing one.

1. almost any 14 inch electric fan will pull more than the mech. fan at 100%. That being said, the mech fan only spins fast at high rpm's. Last time i checked i dont floor it when im crawling :)

2. ON/OFF switch for the electric fan. So if you know you are going into water for a second turn off your fans and you will be just fine.
 
Why not stick with the stock set up and keep one of each type & set your e-fan up to be switched?
 
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