I need advice on which way to go on this.

I pulled the head to take a look inside. Please offer any diagnositc direction on determining where the oil is coming from. I have a fresh 4.0L head I can put on here but don't want to do it if the block is screwed up. Should I give the head to a machine shop to see if he can find anything?
I'm going to pull the valves on #2 and see what those look like but I wanted to post these to see what you guys think..

Here are the things I noticed.

The head bolts, some (a couple) had rust to a degree which made me question the quality of the ability to retain a torque. Others (about 60% were ok with a thin film of some kind of oil. The others were heavily satuated with
this funky oil. Man, this stuff stinks like the funk of 40,000 years. I don't know if this is normal or not or where this oil comes from.

I looked at the valves on #2 and they feel pretty snug there. It felt ok, both exhaust and intake.


I look at the cylinders and they "feel" good to the touch. Smooth. On the edge at the area between the cylinders (on the top rim of the cylinder wall at the area where two cylinders are closest) there is some crusty, looks
like carbon.

The gasket looks good as far as I can tell. There is a "wet" area around #2 bleeding out to the driver's side of the engine.


Anything else I can look for on this?

http://members.bigvalley.net/wuji/jeep/engine/head1.jpg
http://members.bigvalley.net/wuji/jeep/engine/cylinder2.jpg
http://members.bigvalley.net/wuji/jeep/engine/cylinder3.jpg
http://members.bigvalley.net/wuji/jeep/engine/cylinder4.jpg

It looks like to me the #2 cylinder has bad rings or a bad head on it. Mine looked like that when i took it off except that there wasnt that much oil. And the oil on the sides looks like a bad gasket placment. Doesnt look to me like it got a very good seal. Did you put the head on yourself? Or do you have something to put it on with. I called up 2 buds and had one help me lower the 96lb. head on while the other lined up the gasket. If the engine hasnt been rebuilt before i would have to say the head is leaking. The grooves on the intake valve are prolly non exsistant now. so oil may be coming in from there. hard to say. hmm good luck bud <img src="/forums/images/graemlins/kewl.gif" alt="" />

<img src="/forums/images/graemlins/frown.gif" alt="" /> Howdy DaJ First off the head bolts. They actually strech when torqued to desired setting sort of like a rubber band... They retain this thru out the time they are in the head. i am sure the rust you see has nothing to do with the oil leak.
Now just from looking at your great photos I would say that you might have a good feeling for the oil... It could be that the head bolts were never torqued to specs or that they were reused from the original engine and with the 2ed torqueing they indeed lost their strech over time. i would have a knowledgable person look closely at that engine in person. Also taking the head to a head shop is a good idea too. Tha is all I can say from just the great photos.
Big Jim

I don't want to tell you what to do, but I would send the head out for testing, AND pull that #2 piston. You would only hate yourself, if you went through all this and had to pull the head again to replace a bad oil ring. Just my opinion, but you already have done the hard part of the job. Oh yeah...If there is any way for you to get new headbolts, it is best not to reuse them...Good luck...Mike <img src="/forums/images/graemlins/oink.gif" alt="" />

that oil leak is a wee bit bigger than i amajined it.... as everybody else has said... take the head to a shop, make sure the new gasket goes on perfect, and pull the number 2 piston. it shouldnt be too hard, just drop the oil pan and remove the end cap from the piston connecting rod and push it back up. you will need a ring compressor to get it back in though... i also was wondering who did the head conversion?/ could some of the oil and water passages not been seal/cut right??

Ok, I just had a 4.0L head surfaced and a 3 angle valve job. It's sitting on my kitchen floor looking pretty tasty. I have a 4.0L Exhaust manifold coming in the mail by Friday. I could have the whole thing put back together by this weekend including the rings on #2 barring complications.

Do you think this is a risky move?

How do the other cylinders look? Do the look normal?

When I take the 4.2L head to the shop shall I ask them to clean and inspect only for informational purposes or are you suggesting this in anticipation of reuse on my engine?
Am I looking for cracks or some other ways for the oil to get in?

I did look at the cylinder in question by pulling the valves and feeling for movement. They "felt" good. The valve seals are new as most of you know.


Thanks guys,

ya take the head to get looked over by a pro he will tell you if he finds a problem, with as much oil as you had leaking by if there is a problem it will be very obvious. couldn't tell by the pic... can you still see the original honning marks??? if you can still see them and they don't look worn all wierd... its a bit easier than pullin out your calipers. as for #2 cyl. take it out and inspect the rings, you should [ay real close attetnion to the oil control ring, if it's all pluged up or don't look right, replace it.

This is what I'm going to do.

1. Take the head to a machine shop today to see if he can find anything wrong with or around #2.
2. Edit: I'm going to pull the piston from that cylinder and inspect/change the ring(s).
3. I'm going to put the 4.0L head on instead of the 4.2L.
4. Change the injector to another cylinder far removed from #2 (maybe #4 or #5).

If everything goes well I should be done by this weekend so we'll see what happens then.


Some questions I have.
1. What's the best way to prepare the block for the new head? How to clean it up, etc?

2. I didn't feel any lip at the top of the cylinder that would call for a reamer but there is carbon crusted there. How should I take that off? Should I get the reamer anyway?

3. Regarding the push rods and the new head. What should I do in this situation since the head is totally different and therefore cannot match up "worn" parts.

4. Can I, should I replace only one ring or replace them all?

Thanks for any information.

Good luck with the mod. Im looking at possible doing this mod at a later day. right now im gonna have to rebuild my shortblock...good luck man <img src="/forums/images/graemlins/kewl.gif" alt="" />

<img src="/forums/images/graemlins/drunk.gif" alt="" /> What I like to do under circumstances like this is to:
1. I would take fine sand paper in HAND and lightly scratch the surface of the cylinder wall in a circular/up and down motion.
2. Then I would scrape the surface of the block and clean it with carb cleaner, I would clean the cylinder with a cleaner soaked rag.
3. Now I would lube the cylinder.
4. The piston should have printed on it how much oversize it is if at all. A complete set of rings should be installedon the one piston. I would choose cast iron for this job.
5. Relube the piston and the cylinder and install the piston/rod.
6. Reclean with carb cleaner the block and head. I would NEVER use any type of sealer here.
7. Install the head making sure everything is DRY and very correctly lined up.

I am not aware of the length of the push rods needed for this mod. If it calls for the length you have...use them!
If there is no ridge I would have sanded a little more on the carbon buildup and it would no longer be there. I would not go for the ridgereamer... Not for fixing this problem.
Big Jim