overheating!!!!!!!!!!!!!!!!!!!

so my jeep is running hotright around 235 or 240but only under heavy throttle. when im cruising it stays right around 215-220. And sometimes when I stop after heavy throttle, and I don't mean to the floor going like hell heavy throttle just dropping a gear going up a hill, anti-freeze come out of the cap. I end up having to leave the jeep running for a minute so it cools down. im running a 180 t-stat. whats my deal?

rcliftedXJ said:

so my jeep is running hotright around 235 or 240but only under heavy throttle. when im cruising it stays right around 215-220. And sometimes when I stop after heavy throttle, and I don't mean to the floor going like hell heavy throttle just dropping a gear going up a hill, anti-freeze come out of the cap. I end up having to leave the jeep running for a minute so it cools down. im running a 180 t-stat. whats my deal?

Click to expand...

bad cap, not staying under pressure.

could be a lot of things, what have you done to diagnos the problem? check coolant level and condition, checked operation of both fans, checked condition of hoses, checked temp of lower and upper rad hoses..?

Need more specs on the Jeep such, most importantly year as the older XJ's have a different type of cooling system.

profile says 97, i'd get a new cap and a t-stat from the dealer to start

doug

I just put in a new t-stat, both fans are running fine, hoses all seem to be fine. i haven't done a very thorough check on the lower hoses but the uppers are fine. coolant looks good. this same thing happened to me last year just after I came out of a good sized hole. so I took an air gun and blew out the mud from the radiator, changed the t-stat to a 180 and didnt have any other problems for the rest of the season. now I'm back out and on really hot days, yesterday was 86, it is kind of hard to keep the temp below 215-220. I do think the cap is bad. the temp gauge read something like 225 or so and it was releasing. i'm not sure if thats were it's supposed to or not.

First of all the 180 T stat really isn't doing you any good. When it's open, 180 or 195, its open. At 215 a 180 cap isn't any better. It just opens earlier and lengthens the time the computer runs in open loop mode.

Older cars need new radiators. Internal corrosion really blocks the flow and heat transfer. You could do the vinegar flush and possibly increase heat transfer, but what you have is the classic symptom of a 12 year old car. A two core radiator is the best solution.

The cap may be bad - but with 16 pounds and 16 degrees added temperature, it can run 228. If it's releasing, its a pressure problem, not a temp problem. You can try a new cap, but I'd be concerned if it started blowing coolant, too. It's a prime symptom of a internal leak from the combustion chamber to the coolant.

At that point, ginseng tablets, or sodium silicate could save the day, and your head gasket, before it goes too far.

ginseng tablets? really? how does that help. I put a new cap on saturday and there was no releasing. I still overheated, but only when I was driving down the road. It never did it when I was on the trail.

So are your symptoms different now with the new cap? In the first post, you were good going down the road.

Coolant "looks fine" but how does it test?

Fans are "running fine" but what does that mean? Two electric fans?

When was the last time a cooling system flush was done with a commercial flushing agent?

Have you checked your fan clutch? A ZJ fan clutch is a great cooling upgrade. As well as hooking up your elec. Fan to a relay and toggle switch. Any coolant loss?