Getting the Jeep to run cooler..

[TheMonk]

Got any hints, tips or tricks to make it run cooler? Mine is running at around 210, untill I'm in stop and go traffic or wheelin hard... then it goes up in the 220-230 range. Very recently I have installed a new Rad, water pump, thermostat housing, hoses, coolant bottle... basically you name it its new. So I'm pretty sure there is no problem, I just would like to be a little bit further away from that bad red line, haha.

 

[Bounty__Hunter]

A friend of mine has been battling a similar heat problem for a year or two, replacing most everything. He bought an IR heat gun to check temps across the radiator and at each hose. His last venture was to install the valve in the pic below. We went wheelin Saturday and we weren't on the trail long when his temp shot up to 240º with the valve open. He closed it a bit, and as he found out during earlier testing, the jeep cooled down and ran cool the rest of the day. His conclusion was that the coolant was moving too quickly through the radiator and/or the fans were not sufficient at cooling the radiator before the coolant exited.

 

[dingus]

fan clutch?

 

[90Xjay]

A friend of mine has been battling a similar heat problem for a year or two, replacing most everything. He bought an IR heat gun to check temps across the radiator and at each hose. His last venture was to install the valve in the pic below. We went wheelin Saturday and we weren't on the trail long when his temp shot up to 240º with the valve open. He closed it a bit, and as he found out during earlier testing, the jeep cooled down and ran cool the rest of the day. His conclusion was that the coolant was moving too quickly through the radiator and/or the fans were not sufficient at cooling the radiator before the coolant exited.

Excellent thinking on his part, having the coolant flow too fast not giving it time to shed the heat IS a problem on alot of 4.0s

I would also suggest finding someone with a heat gun and verifying that your coolant is actually as hot as the gauge says it is before you spend any money .

 

[Dry suit diver]

how do you solve the opposite problem???

mine runs at less than 100 degrees C all the time ( 212 farenheit) even when the top hose split and dumped coolant all over the engine. not a problem in summer as no overheating problems inn traffic but boy its cold in the winter


4.0L 1996 cherokee.

 

[Saurian]

Check the thermostat. We had this problem on a chipper truck at work, it's kind of interesting, really that such a silly little part can cause both overheating, and overcooling. In our case, the thermostat was stuck wide open, causing the coolant to not be held in the engine long enough to heat up. The truck never got up to temperature, the heat from the vents was lukewarm, and it was going through gas like we were getting it for free...

It should be sitting right at, or slightly under 212 when all is said and done, a tiny bit more on a hot day, and a tiny bit less on a cold day. If you are there, and you feel heat on the upper radiator hose after it has been running for a while, properly warmed up and everything, I would suggest that your problem might be more in the nature of a plugged heater core, or a faulty blend door...

 

[O2Hammer1]

Just wondering what the temp would have been when they were new? I have a used "99" and it runs about 210 just on the road. I never really thought it was runing hot since it always ran at half way on the temp guage. But recently i noticed the antifreeze level was low and did see the expansion tank was a little wet at the over flow port. any reason for a major concern here? I'm getting ready to start using it on the beach, it's all stock right now and I don't anticipate any heavy use without getting everything checked out first.