Running hot
09-19-2012, 12:18 PM
#19
Old fart with a wrench
This may sound stupid, but check you lower radiator hose for internal collapse. It does happen. Not often, but it does.
09-19-2012, 12:24 PM
#20
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Year: 1992
Model: Cherokee
Engine: 4.0 HO
Do you have a trans cooler? I don't know much about the Grands, but if it's setup similar to an XJ (trans lines run into the radiator) your transmission could be overheating. If you don't have an external transmission cooler it might be worth installing.
09-19-2012, 12:36 PM
#21
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Year: 1994
Model: Grand Cherokee
Engine: 5.2L V8
The lower hose is fine. Already checked it. I don't have a tranny cooler. The lines go into the radiator. I think I'm gonna get an external cooler.
09-19-2012, 06:27 PM
#22
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Year: 96 Limited ZJ
Model: Grand Cherokee
Engine: 5.2 w/mods
Most ZJs with the tow package came with a tranny cooler. 3 of my i6 Grands had them and my V8 has it, might be able to get it cheap at a pull yard.
09-19-2012, 10:13 PM
#25
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Year: 1998
Model: Grand Cherokee
Engine: 4.0
Originally Posted by mrtoofast4u
Get this, I turn my overdrive off and it doesn't run hot.
09-20-2012, 03:51 PM
#26
Old fart with a wrench
Here's an off-the-wall idea. Is your drivebelt routed properly? If the waterpump is spinning in reverse, it won't give much flow.
As I said, It's an oddball idea.
As I said, It's an oddball idea.
09-20-2012, 07:57 PM
#27
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Year: 2004
Model: Grand Cherokee
Engine: 4.7L V8
Your injectors may be a little clogged causing it to run a little lean. This would make it run hot under a load. When I had my '97 V8ZJ, it did the same thing in the Tenn mountains. I had some injection system cleaner ran through it, and what a difference it made. More power, and no more climbing temps when climbing those grades.
Before doing it, the idle was smooth, and power was good, so I didn't know if it would help, but I tried it anyway. I was glad I did.
Might not be your issue but it sure did help with mine.
Another thought: My son bought my ZJ and now he wants to replace the injectors w/some newer ones w/a better spray pattern. I've read threads where people use the 784's or 789's in their 4.0L, and wondered if anyone's done it with their V8 ZJ? If so, what were the results?
Before doing it, the idle was smooth, and power was good, so I didn't know if it would help, but I tried it anyway. I was glad I did.
Might not be your issue but it sure did help with mine.
Another thought: My son bought my ZJ and now he wants to replace the injectors w/some newer ones w/a better spray pattern. I've read threads where people use the 784's or 789's in their 4.0L, and wondered if anyone's done it with their V8 ZJ? If so, what were the results?
09-21-2012, 04:04 PM
#28
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Year: 96 Limited ZJ
Model: Grand Cherokee
Engine: 5.2 w/mods
Another thought: My son bought my ZJ and now he wants to replace the injectors w/some newer ones w/a better spray pattern. I've read threads where people use the 784's or 789's in their 4.0L, and wondered if anyone's done it with their V8 ZJ? If so, what were the results?