When the fan clutch was replaced was the fan put on the correct way. If it was put on backwards it would cause this to happen. The fan would be pushing air through the radiator instead of pulling it through from outside. Start the jeep and open the hood you should feel the blowing towards the engine if you don't then it is on backwards. Or place a piece of paper on the grill and see if it gets stuck to it or get blown off.

 

Haven't pressure tested yet but it seems to hold pressure because it will get the cap hot and hoses firm. Going to do compression test now and check for a warped head. Thats about the only thing left it could be. Im still not getting any oil/water mix. I checked the cap and rotor and plan to change both of those too. Fan clutch and fan are installed correctly.

 

Yeah you already mistakenly changed the head gasket, why bother with a silly 5 minute pressure test when you can change a head out.

 

Wont the compression test give me the info on the head? Just realized its $240 to rent the coolant tester lol

 

Not the info you're looking for.

You want to see if you have a cooling system leak.

It's a 5 minute test. Pump it up to 15 or 16, whatever, and it should hold pressure. If not it's leaking somewhere, maybe the head, maybe elsewhere, but if you don't see anything dripping while its pumped up and the gauge shows it leaking, then you can start to assume it's internal. But you already changed the head gasket....was the old gasket showing any sign of leaking?

 

No the old gasket and everything looked pretty clean and normal. I have had any coolant loss or coolant in the oil no white smoke. I would think id get some of that if there was ever leak. What would a warped head act like on these?

 

..

 

Ok. Well thanks for all your help.

 

Okay, I get it. You do not want to do tests, you want to swap parts, and you're here to get advice on which parts to swap. Got it.

It's your time and money. I'm out.

 

Ok thank you too. This is my only vehicle so i cant just run out and get testers and parts anytime. my next move is to test the compression.

 

You can rent all the test tools you need at auto zone for free

 

I havent been able to get to autozone lol
Ok so compression test as follows

1-150
2-140
3-150
4-160
5-145
6-150

This was with all plugs out coil and fuel un hooked.

Pressure tester is hooked up now holding 15-16psi engine off. Do i need to run the engine?

 

 

Ok a little more testing before i returned the tools. Left the pressure tester on the cold engine and it held 15-16 psi for over an hour. Next I ran the engine with the pressure tester connected. Pressure on tester got up to 12 psi but my gauge read 240 degrees and i felt like my hoses were way too tight so i shut it off and removed the tool. Never found any leaks with pressure test.

So after the test i fired it back up with the rad cap off in hopes of maybe some more air burping free. At this point it has been idling for 30+ mins. Hooked up my obd2 scanner for live data and shows 210 degree coolant gauge showing 240. replaced cap. Decided to drive it some, about 4-5 miles and gauge got up to around 240 again. Oddly my obd scanner had dropped to 150 degrees.

Decided to bring out the infared reader and this is what i recorded at idle after the above.

Gauge


OBD live data


Infared temp at sensor in thermo housing


Infared temp at thermo housing


Infared temp at Rad cap


Infared temp at radiator core by lower hose


All these pics are take back to back while idling

I think its odd my obd scanner jumped from 210 to 160 on a 5 mile drive, then again this was at night not during the day when its 95+ degrees outside. But it hasn't registered a temp that low since ive started all this. All in all my readings seem all over. The aux fan comes on with ac but hasnt gotten hot enough to turn on by itself but once during a day test drive and then my obd scanner was reading 223 degrees. Im stumped.

 

could it possible that you have to wrong sensor for the gauge. In 96 there were 2 different instrument panels one with gauges and one with out but there were 2 different sensors to go along with that. The one in the thermostat housing is for the computer and the other one is for the gauge.