Alright,

I have posted on here a couple of time for help with my XJ's overheating issues. Currently the following have been replaced:

- Rad, replaced with all metal 3 core rad from radiatorbarn.com
- T-stat and housing, replaced with 190deg and hiflow tstat housing
- Hoses
- Heater Control Valve
- Water Pump, replaced with Bosch hiflow water pump
- Coolant Sending Unit
- Coolant Temp sensor
- Added secondary temp gauge
- New coolant/water mixture
- Rad Cap

As of this evening, when idling it will warm up to 210 and then tstat will open and the temp drop slightly below 210 and then start to rise toward the red. While driving, the temp will start to slowly rise above 210. sometimes it stays steady at 210 or just slightly above and then other times it will be inbetween 210 and the mark before the red.

I am going to try to burb the system for the millionth time and see if this helps. With the cooling system upgrades, I can not understand why I am having issues. I figured I would never have issues again!!! Otherwise, I cant think of anything else besides a warped head. I do not have any coolant in the oil or smoke conditions but I am out of options. I hate to say it, but I am tempted to bring this rig to a shop and see if someone else has more luck. PLEASE HELP!!!! If you know something I dont please include me in on it!!!!

Any and All help would be GREAT!! Thank you in advance!!!!!!!!!

 

Are you sure that your fan clutch is working correctly and that the fan is actually running and cooling when needed?

Also is there any blockages in front of the radiator that are preventing air from passing through correctly?

and just because you replaced the Tstat doesn't mean it is working right, I have bought new tstats that were bad.

I would pull the tstat and run without it for a little to see if you still overheat, or at the very least boil the tstat and visually watch it open.

 

get your system flushed at a shop. your heater core is m ost like gunked up. 210* is normal operating temperature.my jeep runs between 210-215

 

it will definitely heat up with a thermostat. thermostats slow down the flow of fluid so it stays in the radiator long enough to cool. no thermostat = no cooling

 

Does it show the same thing as the factory gauge?

 

Sounds like it could be viable, But whenever i used to do it in my 240's it would actually help keep it cooler.

Maybe jeeps are different?

I know no tstat in my cars helped run them cooler cause the tstat is used to keep engine at op temp not help keep the water cooler. I also would keep them in closed loop instead of open loop though so i got worse gas mileage

Actually i just searched and I was right, A thermostat is to maintain optimum operating tempeture of the engine by restricting water flow so the water heats up and warms the engine, Meaning i was right, If you REMOVE the thermostat it will run cooler because the water is cycled through the radiator more oten and at a faster rate then if a thermostat was used.

 

the way jeeps operate is different than alot of vehicles. i know in my mustang i never ran a thermosat.

 

lol +1 to that brother!

Jeeps are just fun enough to keep me addicted and just enough of a pita to keep my hair fallin out lol

 

also restricts for cooling purposes as well. removing the restrictor will not let the coolant sit in the radiator long enough to cool. i thought the same thing originally about removing or putting in a lower thermostat. i did it and i caused more overheating. i didnt listen at first but i have since learned

 

If coolant temp is 210F, even a 195F t-stat will be virtually wide open and coolant will be flowing through the rad and engine at the the same speed.

http://www.stewartcomponents.com/tec...ech_Tips_3.htm

 

I also replaced my fan clutch as well but I am not sure. I will check the fan operation today and the blockages and report back!

 

No, while the factory gauge shows above 210, the secondary gauge shows approx 160-180

 

If my heater core was gunked up wouldnt it affect my heat as well?? I currently have no issues with my heat.

 

http://www.stewartcomponents.com/tec...ech_Tips_3.htm

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Fan clutch and electric fan.