overheating

[86customanche]

I have a feeling that this is a somewhat common problem but my MJ overheats while wheeling it. On the road, everything seems just fine and dandy, no heating issues, but when I'm wheeling at low speeds/high rpms, it tends to overheat after awhile. I'm curious as to what is causing this to happen. It usually is fine until I have to go up a steep hill or through a mudhole where the rpms are very high for very low speeds. A PO had installed a second fan on the radiator on a switch that I'm guessing was used to help prevent this issue but one of the fan blades has been broken since I've owned the truck so is no good. Do I just need to replace that fan and use it off-road? Or is there something else that I could do?

[86customanche]

This is on my 92 MJ trail rig in my sig

[ftpiercecracker1]

fix the fan for sure, check your clutch fan might need to be replaced, maybe refresh/clean your cooling system, i.e. new coolant, flush the motor could be gummed up a little, check the front of your rad could be stuffed with leaves and crap

 

the stock cooling system on our MJs isnt exactly heavy duty, one way to ensure you won't over heat, that i have done personally, is just remove the t-stat, maximum coolant all the time, but i wouldnt recommended it.

[skidoo_j]

You need to fix the electric fan and maybe replace it with a '96 12 blade fan. The reason being you need more air movement the higher the cfm rating of a fan the better. When the engine is at high rpm the engine driven fan does not move much air as the clutch opens and the fan will actually slow down some. The clutch is driven in this way as the truck was designed to be going 25 mph down the road when you have 2500 rpm ish...

 

 

Another option if this is a trail only vehicle is to remove the clutch fan and replace it with an electric fan. There are a few people on here who have replaced the stock clutch fan with a stock acc fan, then wired each electric fan to different temperature thermostats with an override switch.

 

you could also replace the radiator with a better or 3 core radiator

[86customanche]

Ill probably end up replacing the radiator, might even add a new electric fan while its out to make things easier. Any different brands of 3 core radiators better than another? And is that 12 blade fan my best/easiest fit?

[Motion Offroad]

Between a 3-core CSF raditor, Hesco Hi-Flow pump, and a set of hood vents I've never had an issue with with our trail-rigs wheeling all day long in 90deg temps. Not all of them run the Hi-Flow pump...