What is wrong with this engine ???
 

Symptoms :

Losing coolant front of engine. Possibly water pump.
Drained coolant, Oil and and smell of gas in coolant. Alot of coolant missing.
Not a milky color, more of a coffee color.

I'm thinking blown head gasket, so I do a compression test.
All cylinders GOOD. 115-120 psi all 6 cylinders.

So I pull valve cover, no visible problems.

I pull dipstick and level is 1 inch above Full. The Coolant must be leaking into oil pan, but from where? All cylinders have good compression.

Any ideas where I should look next?

I'm trying to pull oil pan, but I can't remove it past front axle, any ideas on how to get it passed the axle ???

Possibly a leak in the block, but where ???

Sounds like a partially blown head gasket to me with that much coolant in the oil. Maybe a cracked engine block but, the head gasket makes more sense to me. As far as getting the oil pan off, jack up the front of the Jeep by the "frame" so that the suspension can droop. This will give you more room between the oil pan and the front axle.

2001 XJ...

Junk it.

good compression on all cylinders? sounds like a cracked block.

Cracked 0331 head?

Lift the body and let the suspension hang to get the oil pan out. You might have to jockey the axle a bit with a floor jack.

Ditto on the cracked head. Since you'll be pulling it either way you can check the gasket and the head/block surface just to make sure.

Pulled the head. No obvious damage. Head cyl #3 & #4 water passages plugged by black sludge. Could not see a crack.

Pistons look o.k. Cyl walls o.k.

Options ?

1. Get improved 0331 head and reinstall.

2. Pull the block and rebuild this engine.

3. Pull the block and exchange for remanufactured engine. Does anyone offer a reman with the improved 0331 head. ????

4. Just plane this head and throw it back together.


I am leaning for option 3. Not sure I can rebuild it myself for less $ than a remanufactured engine. No warranty either.

That black sludge goes by the trade name "stop leak" and it's everywhere now. You may be able to reuse the block after it's boiled out. Needless to say the entire cooling system will have to be replaced.

Notice the intake valve on #3? It's a different color than the other intake valves, kind of like it was steam cleaned.