cooling fan question

I did a search and couldn't find anything significant about this...also, wasn't sure if I should post this in the OEM Tech or Modified section, but here is goes...

What do you guys think about replacing the standard pulley fan and clutch with something like a 'flex-lite' fan...a straight fan blade (with spacer)...no clutch?

Would this do anything to aid in keep things cool (cooler)? I know that the coolant temp is controlled by the thermostat, and I've read a lot of stories on this forum about XJs overheating and running hot (mine goes up to 210 and stays there all day while driving). But was wondering if a direct drive fan would provide quicker cool downs...maybe even make the AC work better???

thanks.

I couldnt find one to fit
the stock xj fan is tiny

Ok several things working here....

210 is the proper temp to run at...that is normal for a XJ.
Next...Without a clutch, you risk over cooling...Doubtful but you risk it and then the computer will dump more fuel to warm up the vehicle to 195 -210 temps.
Next...I haven't looked at flexolite straight blade fans for mounting on a pully...but I just got done with an electric fan install. More tech on that later when I finish testing the setup.

Depending on the year of your XJ...your e-fan may be controlled by the ECU or on the renix systems...controlled by a temp SWITCH hooked to the radiator.

So i guess more info is needed...Hope some of that helps.

Thanks.

I have a 2000XJ...the cooling system is just fine...the e-fan kicks in at ~215-220.

But the e-fan doesn't always kick on with the AC is turned on (had system check...they 'said' everything seems okay) and there is a lot...a lot of heat under the XJ hood once it reached operating temp. Sometimes you have to have oven mits just to be able to open the hood. And when the e-fan does kick on...you have feel a lot of heat being pushed out from underneath the vehicle.

I just thought that a non-clutched fan would keep things cooler under the hood and make the AC work better...work faster. It seems that you have to be moving in order to get really cool air from the AC.

thanks.

I read on one of the xj sites (I forget which) where someone made a new bracket that the stock fan attached to. So it did away with the stock clutch setup, and just kept the fan spinning all the time.

Seems easier to just weld it somehow and be done with it. If thats your goal.

Bouncy said:

Next...Without a clutch, you risk over cooling...Doubtful but you risk it and then the computer will dump more fuel to warm up the vehicle to 195 -210 temps.

Click to expand...

I don't think that overcooling would be an issue because you wouldnt be able to make a significant difference using the direct method. could you cause the engine to run cooler than 180 without a clutch? Not in socal unless its 40 degress outside. Example, for those that move to the dual flexlite setup, do they need to make any computer adjustments doing this mod?

thebrick said:

Thanks.

I have a 2000XJ...the cooling system is just fine...the e-fan kicks in at ~215-220.

But the e-fan doesn't always kick on with the AC is turned on (had system check...they 'said' everything seems okay) and there is a lot...a lot of heat under the XJ hood once it reached operating temp. Sometimes you have to have oven mits just to be able to open the hood. And when the e-fan does kick on...you have feel a lot of heat being pushed out from underneath the vehicle.

I just thought that a non-clutched fan would keep things cooler under the hood and make the AC work better...work faster. It seems that you have to be moving in order to get really cool air from the AC.

thanks.

Click to expand...

I don't have a 2K, but I've seen it discussed here that the late models, 00 and 01 the fan does not run whenever the AC is turned on, but only wen certain conditions are met. it was discussed a few pages back, the conclusion was that the AC senses temperature or some mumbo jumbo and knows when to turn on the aux fan.

I think there isnt alot of room in front of the fan. I would be afraid that one of the flexible fans would pull itself into the radiator.

djblade311 said:

I don't think that overcooling would be an issue because you wouldnt be able to make a significant difference using the direct method. could you cause the engine to run cooler than 180 without a clutch? Not in socal unless its 40 degress outside. Example, for those that move to the dual flexlite setup, do they need to make any computer adjustments doing this mod?

Click to expand...

Guess I am speaking more from the state shaped as a MITTEN. Michigan has a wide range of temps...Thus:

When cold out...With a welded fan, the fan would cool more than needed and never let the motor get up to temp for the ?? open loop or closed...?? Can't keep that straight in my head.

On a hot day...It turns faster at idle cause its welded...cools better for sure. But if you still have a problem, your stuck.

I have the over heat issue on the trails or stuck in traffic. Installed the flexolite model 110...fits great...Wont do shit for keeping it below 210 degrees. It keeps it at about 215 with the fan continously running and it sitting idle. This was from a COLD START UP and just sat there idling. Though the aux fan did bring it down to about 195.

Model 110 flows 1250 CFM and in the instructions in FINE PRINT..Let me say that again...FINE PRINT it says for motors of 125hp and below.

Flexolite has a model 210?? that is a dual fan flowing 2500cfm. Going to order and try it next...If not, summitracing gets the whole thing back and I go to mechanical again and start exploring pushers with the mech fan in place.

Mines a 1990 XJ with an HO swapped in. Also has the 10 blade fan for the aux.

Still working this project though.

just to save you all the troubles of trial and error:
http://www.go.jeep-xj.info/HowtoElectricFan.htm

So if normal operating temp for the 4.0L engine is 195-210, why is a 165 thermostat offered for this vehicle? I just picked one up to try in mine before reading this thread. Now I am confused... Should I go back and get the 195 thermostat?

I too am having troubles keeping the jeep away from the top of the temp guage.