Help

I was checking my oil this weekend and I found some foam and what looks like water on the dip stick. The air filter has some blow by and is also wet.
1990 4.0 xj 130,000 miles but its a rebuilt engine with about 30,000 miles on it. I plan on pulling the oil pan and cleaning it out. Anything I should check or should I start looking for a new engine.
Thanks

algeroth79 said:

I was checking my oil this weekend and I found some foam and what looks like water on the dip stick. The air filter has some blow by and is also wet.
1990 4.0 xj 130,000 miles but its a rebuilt engine with about 30,000 miles on it. I plan on pulling the oil pan and cleaning it out. Anything I should check or should I start looking for a new engine.
Thanks

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without personally seeing it I would not be able to tell, blow by in the air filter is normal on the loder xj's. Hve you crossed deep water lately? Have you washed the engine bay? If not Id do a compression leak down test to see if you hve a bad head gasket.

No deep water
Wash?? what is that
I'll check the compression thanks

If you do alot of short runs then condensation on the dipstick is pretty normal as is brown foam on the underside of the filler cap. What happens is that as the engine warms the the air inside which has moisture in it, if you don't get the oil hot enough to cook all the moisture out then when you shut it off it condenses as water droplets, start it up and the oil/water drops get mixed and circulated, when they hit the hottest part of the motor, the head/valve train area the water gets cooked out and condenses, comes out as brown or tan foam generally settles on the coolest part of the engine which is the valve cover.
I try never to run any of our vehicles less than 40 minutes, it generally takes about 3 times as long for the oil to reach the same temp as the cooling system.
Next time you start it up let the engine reach temp then shut it off, check the dipstick and the oil will still be pretty cool to the touch, here in the poconos when it's 10F out the oil is still almost cold after 8 miles to my first coffee stop