Mr.JayDeeM

I read somewhere about heads. 4.0l mind you. They are prone to crack? I have a 00 with 94k miles on the clock. Why would they crack to begin with anyway? Should I be worried about it? Where does the crack usually be on the head? This is something I need to know for future reference.

diskman

Grab a flashlight and look on the head casting between the valve cover and throttle body area on the "lip". You will find a 4 digit number. If it's 0331, it's prone to cracking. There is a better head from the previous years that everyone says to use as it flows better. I forget the casting number though. My '92 has one.

Keep the XJ from overheating. Scrounge a used older head and plan a weekend of wrenching in your future.


Found a pic.

Your number is between cyls 3/4. You can see part of the 0331 number in the lower left corner.

98 JeepJeep

0720 is Supose to flow better overheating is curtain death for the 0331 head.......

(Eckks-Jay)

The 0331 is not as "horrible" as people say it is. If it doesn't crack by 75k, then it's probably not going to. I have an 01 with 200k and haven't had ANY problems out of it. The wife overheated it twice, once when a rad hose busted and another time when the belt shredded, and we've put 30k on it since then.

98 JeepJeep

The main 0331 issues were in 99/00 but should have been fixed in 01..........

Mr.JayDeeM

It just turned 95k today and no problems. No over heating and what not either. I will check the casting number tomorrow when it cools down.