Cracked head on '01. Too late to replace?
08-17-2011, 02:57 PM
#1
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Model: Cherokee
Cracked head on '01. Too late to replace?
I have a 2001 Jeep Cherokee and what I suspect as a much overdue cracked head. I have very very low oil pressure and it drinks coolant. The motor still runs perfectly though.. Is it worth it for me to replace the head? If so which one is recommended. Thanks for your help.
08-17-2011, 03:01 PM
#2
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Year: 2000
Model: Cherokee
Engine: I6
Whats your oil pressure at idle and while running? I suspected mine had a cracked head since it was drinking coolant but it turned out to be a cracked radiator.
08-17-2011, 05:49 PM
#4
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My oil pressure when cold is a normal 40psi. But after it warms up it will drop down to below 10psi at idle. This is with 15w-40. It runs and drives fine I didn't know if replacing the head would prevent any further wear on the internals. The radiator is newish and no leaks :/
08-17-2011, 05:55 PM
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
What does your oil look like? Does the engine knock or rattle? The bearings may not be wiped. If they are it isn't that difficult a fix. I'm pretty sure you can save your engine.
08-17-2011, 05:59 PM
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Year: 1994
Model: Cherokee
Engine: flux capacitor
If you have no engine noise and no oil consumption I'd just do main,rod & cam bearings with a melling hv oil pump. I let mine go too long and I just did a reman head and a hv oil pump which put me around stock oil pressure at n.o.t.
08-17-2011, 06:10 PM
#7
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Year: 2001
Model: Cherokee
Engine: 4.0
01 cherokee newly rebuilt motor
Sorry didnt mean to post on someone else's post. started my own
Last edited by gwayms; 08-17-2011 at 06:38 PM. Reason: wrong post
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08-17-2011, 06:14 PM
#8
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Do not put 50w oil in your engine!!!! Holy crap! What all did they do in this rebuild? They do have special additives for break in but if its tapping loud out might have a bad lifter. Again what all did they do?
08-17-2011, 08:59 PM
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Year: 1994
Model: Cherokee
Engine: flux capacitor
Why not? In the summer I don't see it being that big of an issue, I have ran rotella in a few vehicles with no problems. The winter time is another issue. Heavy oil is like caro syrup when cold which could cause an issue cold but in the warmer months I don't see it hurting anything.
08-17-2011, 09:16 PM
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Even at 100* 50w is too heavy to flow and lubricate. You do damage on start up. Most motor oil will thin out the same at 212.... why would you subject your motor to that initial wear? Your pressure might be high yes, that is because its so thick the pump can't push it through your engine. Go to bobistheoilguy.com and check out oil 101. Get the facts. I run 5-20 or 5-30 syn in my 21 year old engine in 100*+ and it is quiet as can be. There is no reason to run such thick oil.
Last edited by Slick761; 08-17-2011 at 09:20 PM.
08-17-2011, 09:17 PM
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50 weight or 20w-50 weight oil? Straight 50 weight oil I would not put in you engine unless its so worn and Knocking like crazy to help soak up some of those loose clearances.
08-17-2011, 09:21 PM
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Originally Posted by 84zmyfavorite
50 weight or 20w-50 weight oil? Straight 50 weight oil I would not put in you engine unless its so worn and Knocking like crazy to help soak up some of those loose clearances.
08-18-2011, 05:59 AM
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Year: 1996
Model: Cherokee
Engine: 4.0
I've been watching my oil pressure closely on my 159K '96 Sport. Last week it was dropping to about 10 at hot idle and about 20 hot running 2k rpm. It has been gradually decreasing, but the oil and coolant both look fine.
I pulled the connector off the sending unit and it was dripping oil. The only way that would be possible is if the sending unit itself was leaking, so I replaced the sending unit. Last evening it was showing 45# hot idle and 55# hot at 2K rpm.
The new sending unit was $40 at Napa and about a 5 minute job to replace.
Yeah, heavy oil is just a bandaid to cover the noise or too loose clearances.
I pulled the connector off the sending unit and it was dripping oil. The only way that would be possible is if the sending unit itself was leaking, so I replaced the sending unit. Last evening it was showing 45# hot idle and 55# hot at 2K rpm.
The new sending unit was $40 at Napa and about a 5 minute job to replace.
Yeah, heavy oil is just a bandaid to cover the noise or too loose clearances.
08-18-2011, 12:55 PM
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Model: Cherokee
Okay back to my main question lol. How to save my engine. It doesn't knock and isn't using a drop of oil. But my coolant overflow bottle goes down pretty quickly.. and no there isn't a leak lol. What do I need?
