Valve job 2002 Liberty Renegade

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Have started this valve job on the 3.7 engine, 225K miles. Heads at machine shop for valve job and surfacing. Waiting for a good report before ordering gaskets, and other things needed. Tons of questions come to mind.
I have never been inside these engines, and getting to see differences. What is going on with the valve cover gaskets! I have only been able to get one gasket off of the valve cover. What did they use to seal the gasket at the factory?
There were leaks at the rear of the engine and have commented to change the gaskets, but with one off, I thinks i should have just sealed them down? Really impressed with the RTV or epoxy they used.
Anyone want to guess what was happening in cylinders 2 and 4 ?
As
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sleazy rider

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Got a heat gun? It’ll soften the gaskets.

Re: your cylinder conditions - I’d be a while lot more worried about #6! That’s a lot of gunk buildup. Like maybe a water leak from the head gasket into it.
 

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yes on the heat gun, never gave it a thought.
The piston tops are telling for sure. I would suspect a 225K motor to have crud build up. Cylinders 2 and 3 are cleaner for sure. When pressurizing the engine during leak down and compression tests, I found 2 and 3 cylinders would push coolant out of the expansion tank. That was what I didn't want to see, but knew it was really possible.
I am adding a pic of the the left bank. I have cleaned #1, easy to reach. The residue was pretty easy to clean.
Any comment on how much better the engine deck needs to be? I have read many things of what to use and not to use, to clean the surface. Rotary type discs seem to be on the bad lists? A non sanding type disc of course.
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sleazy rider

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I very carefully use a razor blade at an extremely shallow angle to clean any stuff off and wash with brakekleen. Use lint free rags.
 

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Thankfully no, I intentionally mentioned to the head rebuild owner that these motors are known for dropping valve seats.
He said all is good. $300 dollars quoted price, paid, and I'm putting them on.
Lucky I guess.
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Robochop

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Definite bullet dodge there! I have had my best luck with the graphite head gaskets instead of the MLS. Those things have a tendency to leak! Good luck on your project!
 

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Head gaskets, i ordered the felpro gasket kit, assumed i was getting something other than MLS, we will see.
Real big point on torque on head gaskets
First, its a crap shoot to find the correct procedure. The factory manual, i downloaded from this site, says the left and right heads have different torque specs and procedures.? I have researched it somewhat but several say its a misprint?
SECOND THING if your not familiar with blind holes on the head bolts, don't
forget to get the oil out of them first! Ask me how i know.
 

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Head gaskets, i ordered the felpro gasket kit, assumed i was getting something other than MLS, we will see.
Real big point on torque on head gaskets
First, its a crap shoot to find the correct procedure. The factory manual, i downloaded from this site, says the left and right heads have different torque specs and procedures.? I have researched it somewhat but several say its a misprint?
SECOND THING if your not familiar with blind holes on the head bolts, don't
forget to get the oil out of them first! Ask me how i know.
LOL, I have had the same issue. I always use a blow hose to clean them out first! We learn as we go, right? I don't recall different torque specs for both heads. I use the diagram/procedures I got from a Chrysler/Jeep dealer hook up. I also borrowed a "torque to yield" torque wrench from him. It is so much easier to tighten, especially in the car, due to the two separate 90 degree torque specs while tightening. I think you can rent them from a parts store as well.
 

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Not sure, i have since read there is a procedure that is done for that. Not sure what is done?
 

Robochop

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Did they do anything to make sure the valve seats dont fall out in the future?
LOL yes, Don't let the engine overheat! Several people who did always say, I was so close to home I just kept going. Now there's a skip in the engine...
 

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Not sure, i have since read there is a procedure that is done for that. Not sure what is done?
Some engine rebuilders say their valve seats are "pinned" to prevent them falling out. When I rebuilt my 3.7 I bought a head from Rebuilt Engines for Less that supposedly had new "pinned" valve seats installed. I had the other head rebuilt at a local machine shop and asked them to install new seats and "pin" them He looked at me like I was nuts but I insisted. He said that these engines are bullet proof and it wasn't necessary. I didn't know what "pinning" involved at the time but when I got the head back there were several punch marks on each valve seat at the line where the seat meets the aluminum head. To me that is peening, not pinning so I'm not sure if pinning is just a spelling mistake or if it's some other process where a hole is drilled through the seat and into the head and a "pin" is driven in. Anyway, if anyone could shed any more light on the subject.......?
 

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Update cylinder head work. All back together, runs and goes in garage. All sounds good except for and exhaust leak. This valve job, head gaskets, all timing components, is not for the faint of heart. Was not versed on overhead cam engines, but had to learn.
Will be taking it out on drive soon. Question, I have a never seen PART TIME message on dash. Was never there, and didn't use or move the manual 4 wheel drive lever. I have searched and seen some references to this issue but not clear cut, as with many automotive problem. These threads were several years old. Has there been any progress on where to start troubleshooting? I can pull us on the console lever and hear a solenoid sound, off and on when I move the shift lever up or down to normal position, no 4WD.
 

Shankster

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First, its a crap shoot to find the correct procedure. The factory manual, i downloaded from this site, says the left and right heads have different torque specs and procedures.? I have researched it somewhat but several say its a misprint?
Don't know what year yours is but I recall there being a certain torquing procedure in the 02 manual and a different (simpler) procedure in the 03 and later manuals. I was really suspicious of the 02 manual since it had so many errors (I think they used the V8 manual and tried to edit it but missed a bunch of edits. Seems they got it fixed in the later manuals). Anyway, I asked around at the time and talked to the owner of Rebuilt Engines for Less (where I bought a head) and he said to use the later procedure for my 02, despite what the manual said.
 

Robochop

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Update cylinder head work. All back together, runs and goes in garage. All sounds good except for and exhaust leak. This valve job, head gaskets, all timing components, is not for the faint of heart. Was not versed on overhead cam engines, but had to learn.
Will be taking it out on drive soon. Question, I have a never seen PART TIME message on dash. Was never there, and didn't use or move the manual 4 wheel drive lever. I have searched and seen some references to this issue but not clear cut, as with many automotive problem. These threads were several years old. Has there been any progress on where to start troubleshooting? I can pull us on the console lever and hear a solenoid sound, off and on when I move the shift lever up or down to normal position, no 4WD.
There is a 4x4 shift sensor on top of the transfer case. Replacing it should take care of the light! Transfer Case Switch for Liberty P/N: 5083138AA
 

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thank you. I seems what i am seeing this is the go to item. Odd there seems to be two different schools on how to access the switch, through the console or underneath the truck. One video showed pulling the front drive shaft, that seemed like work?
 

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Don't know what year yours is but I recall there being a certain torquing procedure in the 02 manual and a different (simpler) procedure in the 03 and later manuals. I was really suspicious of the 02 manual since it had so many errors (I think they used the V8 manual and tried to edit it but missed a bunch of edits. Seems they got it fixed in the later manuals). Anyway, I asked around at the time and talked to the owner of Rebuilt Engines for Less (where I bought a head) and he said to use the later procedure for my 02, despite what the manual said.
Yes the head torqueing was really a head scratcher. I used the 2 90 degree method on both heads. I think they didn't get the edits done for sure.
 

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