XJ overheating - Off-Road Forums & Discussion Groups

#1 11-09-2005, 06:46 PM

Hello,

I have a 1989 XJ Cherokee with 175k miles on it. I am having some serious overheating problems with this Jeep. I have to carry a couple gallons of anti freeze with me wherever I go because it keeps gushing out of the reservoir tank everytime I stop. I have bought a new reservoir and that didn't seem to help. I have bought the expensive "extended life" anti freeze that is for older cars that run hotter and that didn't seem to help. I am ordering a new super flow thermostat and housing to see if that might help. Are there any other suggestions that I can try to prevent it from getting so hot?

NIX · #2 11-10-2005, 05:03 AM

Check the T-stat. In a used engine mine only opened in boiling water. As soon as i closed the gas and the water stopped boiling, the T-stat closed. Not good. Check if the rad is clean on the outside and if the inside isn't clogged up. Check if the lower hose has the spring in it to prevent it from collapsing. Check if the pump is not the reverse one. Easiest to check is to look in the reservoir with the cap off and see it the coolant is coming out of the side inlet when you rev the engine a bit. Is the pump OK anyway? if you suspct a bad gasket or cracked head check for bubbels in the coolant with a running engine or go to a shop and keep the CO sniffer at the cap...

BigNorm · #3 11-10-2005, 12:32 PM

I love what this guy did. http://www.rightcoastcrawler.com/bil...ents/vents.htm Check out the pics where he cut out the hood. It shows really well how close to the hood that reservoir is. I'll bet venting it would help the reservoir alot not to mention under the hood temps. I'm with Nix though. Check the Tstat first and go from there. The 4.0L is notorious for overheating.

xjy173 · #4 11-10-2005, 10:08 PM

[ QUOTE ]
Check the T-stat. In a used engine mine only opened in boiling water. As soon as i closed the gas and the water stopped boiling, the T-stat closed. Not good. Check if the rad is clean on the outside and if the inside isn't clogged up. Check if the lower hose has the spring in it to prevent it from collapsing. Check if the pump is not the reverse one. Easiest to check is to look in the reservoir with the cap off and see it the coolant is coming out of the side inlet when you rev the engine a bit. Is the pump OK anyway? if you suspct a bad gasket or cracked head check for bubbels in the coolant with a running engine or go to a shop and keep the CO sniffer at the cap...

[/ QUOTE ]

In addition to this above, have the pressure cap tested and replace the cap if it fails the test. [img]/ubbthreads/images/graemlins/smile.gif[/img]

BigNorm · #5 11-11-2005, 02:19 AM

How do you test the cap? Just wonderin'

#6 11-11-2005, 02:51 PM

I would also like to test the cap because the guy I bought the Jeep from had the wrong kind of overflow tank so I bought a factory OEM version that came and I'm still having problems. I have also heard that if the cap isn't pressurized properly that air can get into the system and you have to "burp" it. Can anybody confirm or deny that? Also, any idea how to burp the cooling system?

#7 11-11-2005, 03:32 PM

I converted my 89 from the remote tank to a standard system as found on 91's and newer....and it gives you a real radiator cap....no issues since....

Chances are you have a combination of problems...

If you replace the stock radiator with a 3 core GDI, replace the remote tank with an overflow bottle....verify your t-stat is good....I don't think you will have any more problems.

skippy62 · #8 11-11-2005, 04:03 PM

Check my post on the overheating XJ

#9 11-11-2005, 04:49 PM

[ QUOTE ]
I converted my 89 from the remote tank to a standard system as found on 91's and newer....and it gives you a real radiator cap....no issues since....

Chances are you have a combination of problems...

If you replace the stock radiator with a 3 core GDI, replace the remote tank with an overflow bottle....verify your t-stat is good....I don't think you will have any more problems.

[/ QUOTE ]

Where can I find more information on how to replace the standard system? Is it something that's difficult? I have replaced the alternator and starter in my Jeep but I am certainly not a mechanic by trade hehe.

NIX · #10 11-11-2005, 06:19 PM

First check all the things I mentioned before. You don't want a conversion and still have the same problems as before because you didn't take care of the real cause of the overheating. If you want to go to the opensystem, get a rad with a cap ('91 and later) or put a fllerneck in the upper coolant hose. Lead the thin overflow line to an overflow bottle. CAn be an old overflow tank or even a coke bottle, as long as it sucks the coolant from a low point in the tank or bottle. 1 Important thing is to connect the 2 lines that come out of the old tank to each other as a loop. Otherwise the system will explode with a cold engine (T-stat closed) and the heater off. Quiet easy and as expensive as yoiu please. But the functioning depends of the conditin of the systems' parts. If something is still wrong, the open system won't do it either...