Adding an electric fan

[90PioSport99]

Well my MJ didn't come with an auxillary fan from the factory and I'm looking to add one. I don't care if I have the stock method of it turning on by itself although I suppose it would be nice. Does anyone know how easy it is to do the stock wiring? I've got the sensor that screws into the radiator from one of my XJs but aside from that it looked like it goes all the way back to a fusible link, and I have no patience to mess with that. Has anyone done one before completely plug and play? If not I'm thinking just run it through a relay and a switch and be done with it. And also, since I'm doing this I think I may go dual electric, as long as I run them both through relays, it shouldn't overload anything right? Let me know what you guys think.

Thanks,

Collin

[JeepcoMJ]

honestly, I'd do the relay. it works better.

 

then, i wouldn't do dual electrics...the electric fan will put out nowhere near the power of the mechanical one.

 

aaaand there are stock ones available.

[JeeperjohnfromPA]

I picked up an electric one at the JY, it has the brackets needed to mount it right on the radiator.

My MJ isn't wired for it, so I'm just goin to wire it into one of the toggle switches on the dashboard.

I aquired some of the toggle switches from an old XJ at the junkyard, and will wire it to the rear windshiled wiper motor switch. I'll wire it through the ignition so it will only run when the motor is running, (so I don't leave it on by accident and drain the battery).

I don't plan on wiring it through the relay(s), but I have the full gauge package and will be able to see when my motor is running hot.

[90PioSport99]

honestly, I'd do the relay. it works better.

 

then, i wouldn't do dual electrics...the electric fan will put out nowhere near the power of the mechanical one.

 

aaaand there are stock ones available.

Oh yeah, I know there are stock ones available I have two of the old straight blade designs and one of the new 97+ designs as well. Upon your advise I will just run it through a relay for sure. Thanks guys.

[Oizarod115]

i run dual electric fans by a single switch/relay... it was supposed to be like that temporarily but I'm so used to doing it now it doesnt bother me a bit. plus you'll want to turn the fans off completely at speeds of 45+ since they arent necessary.

 

any front wheel drive car is going to have beefy electric fans the ford taurus is the best option though, i have intrepid fans and the one iwth the big motor died on me. :dunno: i replaced it with the stock electric fan just to get through the rest of the summer but its been 105 every day and she stays right about 210* so i guess its workin' alright.

 

ford taurus dual electric setups pull 4500+ CFM according to go-jeep

[90PioSport99]

i run dual electric fans by a single switch/relay... it was supposed to be like that temporarily but I'm so used to doing it now it doesnt bother me a bit. plus you'll want to turn the fans off completely at speeds of 45+ since they arent necessary.

 

any front wheel drive car is going to have beefy electric fans the ford taurus is the best option though, i have intrepid fans and the one iwth the big motor died on me. :dunno: i replaced it with the stock electric fan just to get through the rest of the summer but its been 105 every day and she stays right about 210* so i guess its workin' alright.

 

ford taurus dual electric setups pull 4500+ CFM according to go-jeep

Good to know, what gauge wire did you use and did you just use the center terminal and top for each of the different fans?

[Oizarod115]

i used 10g IIRC and I'm not sure bout your other question,

 

it was my first relay-wiring experience, and its worked fine so far

 

i did have to move the radiator 1" forwards to clear the fan motor (yeah, the one that quit working :headpop: ) but i believe ford taurus fans don't need much/if any help fitting

[DirtyComanche]

FWIW:

 

I have/had dual ford taurus AUX fans (the littler ones), and they will fit an XJ/MJ well enough. Other than the rad had to go about 1.5" foreward, and the studs on the stock mech fan pulley have to be shaved. I used the smaller ones because the fit the stock rad better without a shroud of any sort.

 

And anybody who thinks they don't work as well as the mechanical fan... They pull WAY more air for the most part. Yes, they won't pull as much as when your motor is at 4-5Krpm, but do you have it there all the time? Well, some people do, but I won't get sidetracked. The point is at idle I can have them CRANKED and keep the motor cold no matter what. Granted, it doesn't make as much heat at idle or low RPM as it does at a higher one, but that's another debate too.

 

 

Anywho, regarding the stock elec fan, don't use the horrible existing wiring. In my XJ, I'd go outside at about 5:20 in the morning in the middle of winter, the temperature would easily be about -35 C, fire up the motor and the fawking fan would come on. EVERY time. Stupid POS. I pulled it for the winter becuase of that.

[Oizarod115]

FWIW:

 

I have/had dual ford taurus AUX fans (the littler ones), and they will fit an XJ/MJ well enough. Other than the rad had to go about 1.5" foreward, and the studs on the stock mech fan pulley have to be shaved. I used the smaller ones because the fit the stock rad better without a shroud of any sort.

 

And anybody who thinks they don't work as well as the mechanical fan... They pull WAY more air for the most part. Yes, they won't pull as much as when your motor is at 4-5Krpm, but do you have it there all the time? Well, some people do, but I won't get sidetracked. The point is at idle I can have them CRANKED and keep the motor cold no matter what. Granted, it doesn't make as much heat at idle or low RPM as it does at a higher one, but that's another debate too.

 

 

 

Anywho, regarding the stock elec fan, don't use the horrible existing wiring. In my XJ, I'd go outside at about 5:20 in the morning in the middle of winter, the temperature would easily be about -35 C, fire up the motor and the fawking fan would come on. EVERY time. Stupid POS. I pulled it for the winter becuase of that.

 

you can see my fans here: http://www.comancheclub.com/forums/viewtopic.php?t=5235&highlight=latest

 

i flipped them upside down in order to avoid the stock mech. fan pulley with the larger fan motor. not sure whats going on with the larger fan :dunno: don't care... it quit workin so i pulled htem, chopped in half, and slapped the factory elec. in with the other fan that works great. been 105 all week and she stays 210 maybe 212 for a second but then back down. (my jeep has always had cooling issues, think its a clogged block :dunno: )

 

the rad. is easy to move forwards if you don't have a/c which most of us don't, just take out ac condenser, drill two holes, pull rubber stoppers out of old rad. mount holes, put in new holes, drop in radiator. and leave the two little rubber things with screw that come througth the brace at the header panel. they don't hold much anyways.