Well I burped the coolant system again and got the temp down and to stay away from 260*.
Here is where it sat

I think if I burp it one more time I might get it down where I want it. So I'm gonna let it cool down and take a nap and do it later

 

Does seem a tad on the high side. My 97 4.0 sits just around the temp of the Tstat which I think is 190 or 200, dont recall

 

Burped it again got out the rest of the air.
Now it sits just below 210 at idle.
the temp would always sit at 210 when driving around and at idle since I bought the XJ.

Now its below 210 be a few degrees when driving and just under 210* at idle.

 

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qué?

 

Are you sure that you don't have a "Zombie" body stuck in front of the radiator??

 

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^which is also illegal in all 50 states if the cat is not replaced with another. We don't talk about doing illegal mods to our jeeps on the forum.

 

Ah you mean the catalytic converter

 

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They way the law on that works is that you must replace the catalytic converter with another one. BUT you are allowed while doing the repair and or testing the vehicle with out the plugged cat to run a TEMPORARY straight pipe as long as you are only testing the vehicle or in the middle of the replacement.

Ex-Auto technician here.

 

None of that should matter, the Thermostat is regulating the flow of the water to the radiator, this is what maintains temperature, and the fan helps, but it's the Tstat doing the temperature regulating. That said, I did check my 97 4.0 just now as was driving and it sits right at 190.

 

Right around where my 01 sits at now

 

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Squealed? That's interesting. Usually squealing is caused by something else. This is the thing you replaced, correct?



On a 2001, the electric fan comes on when the coolant temperature reaches 223° F. It continues to blow until the coolant goes below 217° F. Unlike 1999 and earlier models, it does NOT come on automatically when you turn on the A/C. The A/C only trips it on when the high pressure side of the A/C system reaches a certain pressure.

The engine fan is supposed to be able to keep the coolant temp around 210° in most situations. The electric fan comes on as a backup.

All a cooler thermostat does is delay the time it takes for the engine to get up to operating temperature, which causes you to run rich, prolongs the amount of time before condensation is boiled out of the oil and delays the breakdown and expulsion of volatile compounds in the oil. You ought to be running the correct thermostat instead. If you're overheating, address the overheating problem, not the thermostat.