1998 Jeep. Was running hot... new thermostat. Then a new water pump. THEN a new motor. Then find out the radiator is only half working (fluid through half of it only). New radiator to find it still does it. RE-CHECK of water pump and it's the correct one and installed properly. Gauge isn't faulty... engine still running hot. My mechanic is completely befuddled over this. ANY other ideas as to what the problem could be or what needs to be checked??? Been without my Jeep for 2 months as of now over this....

Thanks,
rayneshwrs

 

Maybe try another tstat. They have been known to be faulty new.

 

thats why you always put them in boiling water first...

 

How hot is too hot? If you're freaking out at 210, don't, that is the normal operating temp for the 4.0. If you're at 230 or higher, then you can start to worry.

 

It ~is~ getting up to at least 230. But even with the new radiator, water is only going through half the radiator. That makes no sense at all to me... Thanks for the input, but if there are any other ideas... and a new thermostat doesn't work, I'll appreciate any other thoughts or ideas.

 

Makes no sense to me either. What do you mean by through only half? If it's only half full, add more coolant.

 

Are both the upper and lower radiator hoses hot?

 

Overheating at high speed or just idling?Lower hose still have the support spring?Could it be sucking shut at high speed?Throwing out ideas.

 

Are the fans coming on at all? If the fans don't come on, you'll still overheat.

 

Impossible to go though just half of the radiator. Add more coolant

 

Never say never.......wonder what the definition of a "new" radiator is.

 

might need to be burped, what about the pump, leaking?

 

Check your fans and thermostat, I had a buddy who put in a new thermostat but when he did he added make a gasket to help with seal, he got make a gasket on the thermostat and it gummed it up. Long shot but he proved it could happen.

 

How do you know the radiator only has coolant in 1/2 of the radiator (top half, bottom half, one side)?? . I'm trying to understand how this is possible and what might be wrong. Where did you buy these two radiators from and what brand?

 

I too am curious on how you are determining that only 1/2 the radiator is working? Also, lets not forget that almost all XJ radiators have the auto tranny fluid circuit too. You sure the 1/2 that is "not working" is not for the tranny? You have a manual or an automatic?