I have a 2001 Xj I just picked up as a project. So far I've had to replace the coil pack and the freeze plug behind the bellhousing. My question is the oil looks very thin and waterery but no signs of water or coolant in the oil. It did sit parked for a month or so before I bought it. I did change the oil but through fresh oil seemsseems water after 400Iles or so. Any ideas?

 

Missing any coolant?

 

None that I can tell. That's what's bugging me. In the past with my 96 xj when the head gasket went I would see thick milky oil and bubbles in the oil I have none of that now

 

If u are using full syn oil it may be hard to tell if water is present.
Do not run the engine until you have tested the oil for coolant.
Let us know.

 

I see no signs of head cracks (0331) but as you can see there are signs of moisture. Any advise

 

Oil analysis only way to be sure.
Blackstone labs or
oillab.com

 

Whether the head is cracked or the gasket is bad you need to remove the head and have it checked for cracks. If it tests good you have the option of putting it back on with a new gasket or getting the TUPY head or reinforced head from clearwater. Of course you have no idea how much damage the coolant has done to the bearings so worst case, you need a new engine. How is the oil pressure?

 

Oil pressure at start up and idle is just at 40psi and drives 40-80, I did do a compression test and all 6 cylinders tested 150psi peak shot to 130psi at first hit.

 

there are no signs of water in that engine. it looks normal. and you'd be surprised how thin oil appears at 220*

edit: nvm I see it now. Change the oil and monitor the coolant.

 

looks like milk shake city to me. get that bad oil out and get some diesel into the crankcase ASAP and start flushing the gunk out, you may save your bearings

 

Going to pick up a new cast head. But I see zero signs of a Crack but there is an obvious problem

 

Cyl #2 is steam-cleaned pretty nicely there. Almost always a head or gasket failure.

 

See below first.
If u don't see a crack send the head to a machine shop specializing in head work.
Have them clean & magnaflux it to determine if the head is ok.
If it checks out have them redo the valves & install new seals.
What is the stamping on your head?
How many miles on the XJ? How many miles did u drive with thin? Oil?
Put your finger in the oil in your rockers and gently stir. Do u see milk?

 

Head was warped. No milk but the jeep has 180k Remember I just purchased and I have all service records. Head gasket was replaced 300 miles before I purchased, it devolved a freeze plug leak and the knocking did not go away. Well I replaced flex plate knocking stopped it was ovaled out at the bolt holes. As this is a project I've oyster put 50 mIles on it.. long story short I drove 3 hours this morning aND grabbed a tupy remaned head, felpro gasket kit and head bolts

 

Glad you're replacing the head rather than machining the 0331. Makes sense.