Just make sure you never allow the engine to overheat. A single overheating episode can cause the (0331) head to crack.

 

Yes, thank you I definitely know that... I don't want ANYTHING to happen to this engine! Thank you!

 

Glad you found the problem and def good that it isn't cracked! See sometimes you just gotta look for yourself before you can know anything for sure

 

After a quick look at the picture you posted with the valve cover removed, I would be really concerned with all that coolant mixed with the oil.

You mentioned you just purchased this vehicle, do any of the engine cooling system parts appear to have been recently replaced?

 

Yeah, I don't think I would be LOLing and hi-fiving just yet......

 

All of that is oil sludge and had a engine flush done yesterday. I asked her if she ever over heated it, she said no.. I do believe her in a way because she has told me everything about the Jeep, and calls me when she thinks of something else.

She did say the radiator was starting to leak one day, so she had it towed right away into the mechanics place and they replace the Radiator, all hoses, thermostat, and serpentine belt.

All fluids including the coolant is perfect, clear (non dirty) and the way it came from the factory. I also put 250 miles on it and never got near the 210 mark, fans come on, no weird noises, etc.

 

I have the exact same XJ. Keep a real close eye on the coolant, I bought mine with 163k and the coolant looked great at the time, but turned to sludge about 15k later. New rad, water pump, thermostat and several flushes later and it's just about revived. The heater core had a ton of crud hiding in it.