I took the head off my 97 XJ because it was using a small amount of coolant. The piston tops for cylinders 1-5 had black stops with no major carbon build up. The top of #6 was whiteish. I could not see any major defect to the head gasket, but it was a small leak. It looks like coolant may have been entering where the water jacket is very close to the cylinder. Is this at all common where head gasket problems are involved in the 4.0? Also, I found that the manifold side head bolts were tight. I put a pipe on a 3/4" breaker bar to get them loose. The head bolts on the passenger side were much easier. I'm not sure that matters because one is outside the valve cover and one is inside. I also found that the passenger side of the head gasket was pretty well stuck to the block. I used a putty knife down the entire side to get it to come up. I am just wondering if any of this is common on the 4.0. I have only pulled the head on one other 4.0, and that had already been done once using a Fel Pro gasket that basically came off stuck to the head. This 97 appears to be "all original".
With good all around compression, 163, 162, 166, 169, 173, 153, I am wondering if its even worth a valve job. I was originally thinking valve job and replace the valve seals. I planned on having both done at the machine shop while they check for any problems, clean it up, and make it ready to reinstall.
With good all around compression, 163, 162, 166, 169, 173, 153, I am wondering if its even worth a valve job. I was originally thinking valve job and replace the valve seals. I planned on having both done at the machine shop while they check for any problems, clean it up, and make it ready to reinstall.
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