suspect cracked cylinder head. yes its a 0331
Senior Member
Joined: Jan 2012
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
at warm idle it was at like 9 psi but at cold idle it was a solid 40. he said he changed all that to stop an engine noise which still continued to be there i think its the lifters which i plan on doing when i get the head off. the oil pressure was so low because the water was mixing with it. when i pulled the valve cover there were drops of water mixed with the oil. i think the motor will be ok because he changed all those bearings and i only put like 400 miles on them with the low oil pressure condition but than again this is all just my theory
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Joined: Jun 2012
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Model: Cherokee
i wouldnt be able to tell you i drove it for a week and didnt think to keep checking it. i didnt even see any water in my oil when i changed it but when i pulled the valve covers i saw it pooled in my rocker arms if i were you i would pull the valve cover and just have a look
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Joined: May 2011
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Year: 1997
Model: Cherokee
Engine: 4.0
after the head is replaced, make sure ur oil psi is minimal 13 psi at hot idle, and above 37 psi when the rpms are above 1600. that is jeeps spec for the 4.0. mine with 175k had 22 psi at hot idle and 37 psi it 1100 rpms when hot. i wouldnt be too concerned if all those bearings were just replaced. i have done plenty of work on bigger engines that have came in with cracked heads and they have fine oil psi after a new head and oil change.
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Model: Cherokee
that really is a load off my mind. after i get the head done if i cant doi it myself im gonna drive it home and change the oil and pour a quart in and let it drain out to hopefully remove all the tainted oil that would be left over
Senior Member
Joined: May 2011
Posts: 749
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Year: 1997
Model: Cherokee
Engine: 4.0
well you really need to flush the system. this is what i would do. immediately after the head. change the oil with some cheap oil and a cheap filter as long as its not a fram, drive it to youre house and change the oil with good oil and a good filter and run it.
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Model: Cherokee
Crack
That is a crack, my 2000 cherokee cracked in the same spot. I took the cylinder head to a REPUTABLE shop and had them weld the crack, resurfaced it and did a complete valve job for $450. No big deal. I thought it was the end of the world as a few members here would say an engine rebuild is in order but weld it and you should be fine.
CF Veteran
Joined: Nov 2011
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From: Montpelier, Ohio
Year: 92
Engine: 4.0
Originally Posted by Decemberist
That is a crack, my 2000 cherokee cracked in the same spot. I took the cylinder head to a REPUTABLE shop and had them weld the crack, resurfaced it and did a complete valve job for $450. No big deal. I thought it was the end of the world as a few members here would say an engine rebuild is in order but weld it and you should be fine.
Seasoned Member
Joined: Mar 2012
Posts: 365
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From: Northern Michigan
Year: 2000 XJ
Model: Cherokee
Engine: 4.8L Stroker
I'm sorry to hear about your head issue. I was jus kidding about having a head for sale. I was referring to the cracked 0331 that I have.
I ran mine cracked for almost 3 years. I couldn't afford a new car or to dumP a bunch of money into the engine. I just added coolan and changed the oil.
I was in the same boat as you. I picked up a junkyard motor with a 7120 head and built that up. That way I wouldn't have to worry about the same issue in the future. Good luck!
I ran mine cracked for almost 3 years. I couldn't afford a new car or to dumP a bunch of money into the engine. I just added coolan and changed the oil.
I was in the same boat as you. I picked up a junkyard motor with a 7120 head and built that up. That way I wouldn't have to worry about the same issue in the future. Good luck!
Last edited by SpruceJedi; Jul 6, 2012 at 08:28 AM.
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Model: Cherokee
I am a certified welder and am very good at welding cast. I would never dump 450 into a welded head. Thats a complete rip off. My local shop will magnaflux, surface and do a valve job for 150, but dont weld it, unless you get someone good, it WILL crack again, and probably worse.
Last edited by Decemberist; Jul 7, 2012 at 03:38 PM.
CF Veteran
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From: Montpelier, Ohio
Year: 92
Engine: 4.0
Originally Posted by Decemberist
Like I said, take it to a reputable shop and you should have no problems. $450 seemed like a steal to me considering I could have spent $700+ on a refurbished 0663. It has been over a year with no problems seems like they knew what they were doing...It's all a matter of preference.
Seasoned Member
Joined: Feb 2012
Posts: 312
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
I have a 2000 as well.
When you guys fill your resevour to the full mark, how much does it rise above the full mark when fully hot?
Its 104 here today and I could have sworn it raised higher than what it has risen to today. Meaning I think it is lower than it was.
Any help is greatly appreciated.
When you guys fill your resevour to the full mark, how much does it rise above the full mark when fully hot?
Its 104 here today and I could have sworn it raised higher than what it has risen to today. Meaning I think it is lower than it was.
Any help is greatly appreciated.
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Model: Cherokee
Senior Member
Joined: Nov 2011
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From: Tampa, FL & DC/MD infrequently
Year: 2000
Model: Cherokee
Engine: 4.0L I6
Originally Posted by Decemberist
Fair enough, but I live in NY EVERYTHING costs more here.
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From: In the middle of Minnesota!
Year: 1999
Model: Cherokee
Engine: 4.0
The vast majority of welds on the 0331 that I've seen have not held over time. Hope you have better luck. But in case you don't, keep a close eye on your coolant reservoir. If it drops, the weld didn't hold.