Need advice! Got the head off...

Ok, I was having the issues with a really rough idle and up to about 2k rpm. I did a compression test on the cylinders and here is what I came up with...

Dry
1) 60 psi
2) 100 psi
3) 145 psi
4) 150 psi
5) 145 psi
6) 140 psi

I then squirted oil into the 1 & 2 cylinders and here is what I got...

Wet
1) 75 psi
2) 120 psi

I suspected the head gasket was probably blown between the 1 & 2 cylinders... I got it all ripped apart and there is no noticeable tear or break in the head gasket. The gasket actually looks cleaner between the 1 & 2 cylinders. Is it possible it was just leaking and I cant see it? The head and valves "look" fine. Monday I will be taking the head to a machine shop to have them do a valve job and clean it up. The cylinder walls also look great. They just have the cross cuts in them from honing.

Any Ideas?

Thanks,
Tom

Have the machine shop magnaflux the head, its only a few bucks more and worth the insurance.

I'll bet you have the little crack between the intake and exhaust valves in number 1. I had the same readings as you, and the machine shop showed me the crack before I ever took the head out of the trunk (threw on the magnet and powder right there as a quick check, it was obvious). Machinist said it's the most common place for the 4.0 head to crack.

It could also be your rings, any cylinder wall scoring? If it turns out to be your head, drop me a PM. I have a head from a '99 I can sell cheap.

Haven't heard on the head yet.... The cylinder walls looked great! You can still see where it was honed and has no ring groove at all... Im hoping its not the head... Or the rings....

Since the oil in the cylinders didn't make a huge difference I'm betting on the bad head or gasket.

Can you guys post up some good websites that sell replacement heads. I would like to go with a new one if the funds will permit. Not to mention I really don't want to go and tear another Jeep down at the JY to get a head. Should I just try and get one through Napa?

I didn't hear back on it today but I would like to have as much research done as I can before I know if its bad or not.

Thanks,
Tom

Since you have a 2000, it is almost for sure a cracked head. Order up one from a junkyard for a 98 and you should be good to go.

Sorry, this one is on my dads 97...