MY buddy's Yj has an overheating problem we can't come to the bottom of it has new radiator and pump we've tried different thermostats and even runnig no thermostat it has electric fan as well. On the road it hardly gets operating temp but as soon as your on the trails it over heats in about ten min any ideas?

 

Yea, my XJ does that as well. About to do the 93+ conversion and get rid of that stupid expansion tank that has blown up 3 times on me. Tried it with and without thermostat, electric fan on all the time... for some reason the cooling system just sucks? I dunno. Maybe i'll try some water wetter too...

 

Maybe not enough cfm with the fan

 

Bigger fan maybe? I think I have a 12 or 13 incher I got from auto zone right now. My jeep only has dummy lights so I usually just flick the fan on when the coolant light starts to show a little red... plus I have the mechanical clutch fan, which I replaced a few years ago... I assume it still works but haven't tested it recently.

 

check your fan clutch
also fan shroud.
make sure everything is working as far as t-stat and water pump.
radiator cap?
also you can verify the temperature using a laser thermometer

also an aux or e-fan would be helpful

the problem is you are not moving enough air through the radiator at trail speeds to get enough cooling. improve the air flow and you improve cooling

hood vents are also used to vent heat since heat rises

 

He is only runnig a electric fan all components are good we took thermostat and it stays cooler longer than with one in it the electric fan is a 14in and pushes a lot of air

 

Bad coolant/water ratio?

 

when you say pushes air you mean pulls air, right? as in theres not hot air blowing out the front of the grill? i know it seems like a stupid question but hooking the wires up backwards does just that

 

only one fan so whats pulling air thru the part of the radiator its not covering?

 

Ya I ment pulling we by-passed heater core and it's runs at about 190-200 at a idle and creeping around in 4l so core must have been clogged thanks for the help guys

 

say what heater core beinng blocked wont make it run warmer ?

 

hm. My XJ doesn't have a fan shroud. Bet that would help, huh?

 

are the fans pushers or pullers and does he have them on there rite