Advice on Replacement Engines
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Junior Member
Joined: Jan 2019
Posts: 33
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Year: 2000
Model: Cherokee (XJ)
Engine: 4.0L
This past December i purchased a 2000 cherokee sport. relatively low mileage (107,000) and a very clean body.
long story short, i had to replace a blown head gasket and found a lot of sludge inside from the past owner missing oil changes, and even after that i still have leaking coolant and low oil pressure. i sent in an oil sample to blackstone labs and they said they found coolant, fuel, and engine metals in the oil. the perfect trifecta.
i really don't want to sink any more maintenance money into it if the engine is on its last legs. right now there's no knocking or idiot lights going off or anything but who knows how much longer until that starts. If i were to replace it, what do you guys recommend? I am a college student with minimal knowledge (basically none) when it comes to engine swapping, and i'm pretty limited budget wise too.
So, stick with the 4.0L? Look for a used one or purchase a new one from ATK or something? swap in a non-jeep engine? rebuild my own? It'd most likely be a shop doing the work, unless I find someone that can help me through it. Does anyone have any reviews on the ATK engines? It's my daily driver so it has to be reliable. I guess I have doubts with aftermarket engines, but I'm new to all this so what do I know. Any advice would be greatly appreciated. Also various cost estimates would be great too. thanks
long story short, i had to replace a blown head gasket and found a lot of sludge inside from the past owner missing oil changes, and even after that i still have leaking coolant and low oil pressure. i sent in an oil sample to blackstone labs and they said they found coolant, fuel, and engine metals in the oil. the perfect trifecta.
i really don't want to sink any more maintenance money into it if the engine is on its last legs. right now there's no knocking or idiot lights going off or anything but who knows how much longer until that starts. If i were to replace it, what do you guys recommend? I am a college student with minimal knowledge (basically none) when it comes to engine swapping, and i'm pretty limited budget wise too.
So, stick with the 4.0L? Look for a used one or purchase a new one from ATK or something? swap in a non-jeep engine? rebuild my own? It'd most likely be a shop doing the work, unless I find someone that can help me through it. Does anyone have any reviews on the ATK engines? It's my daily driver so it has to be reliable. I guess I have doubts with aftermarket engines, but I'm new to all this so what do I know. Any advice would be greatly appreciated. Also various cost estimates would be great too. thanks
Last edited by markhoff1022; Feb 28, 2019 at 11:17 PM.
CF Veteran
Joined: Oct 2018
Posts: 1,096
Likes: 166
From: Hunt County Texas
Year: 1995
Model: Cherokee (XJ)
Engine: 4.0L
Cheapest route will be a junkyard engine from a low(ish) mileage crashed example. You can probably grab one up for a few hundred dollars. Not sure what shop hours are on an engine swap. Probably quite a few. No matter what you do it won't be a cheap proposition.
CF Veteran
Joined: Jun 2016
Posts: 2,138
Likes: 278
From: Santa Clarita California
Year: 2001
Model: Cherokee (XJ)
Engine: 4.0L
I be leave you can use a motor from a Wrangler 97-06 so you can get a newer motor then the one you have I also thing that the cylinder head on the 2003 and newer use the tupy head that doesn't crack .
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Joined: Jan 2017
Posts: 3,402
Likes: 394
From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
Read Cruiser's post on engine swap:
https://www.cherokeeforum.com/f2/che...bility-236512/
Do you have the 331 head? If you only replaced the head gasket you might have missed that the problem is actually the head. See if replacing that will solve your problems.
How much metal is there? Where is it from? Or why is fuel in there? What does the drained oil look like? IIWY I'd try to get a better handle on that before I went into catastrophe mode.
https://www.cherokeeforum.com/f2/che...bility-236512/
Do you have the 331 head? If you only replaced the head gasket you might have missed that the problem is actually the head. See if replacing that will solve your problems.
How much metal is there? Where is it from? Or why is fuel in there? What does the drained oil look like? IIWY I'd try to get a better handle on that before I went into catastrophe mode.
Last edited by Dave51; Mar 1, 2019 at 11:27 AM.
CF Veteran
Joined: Nov 2017
Posts: 3,700
Likes: 238
From: Groton, MA
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
The Wrangler 00+ I6 is different than the XJ. The engine compatibility sticky has the details, but in general you can go with any XJ block, -99 Wrangler blocks and -98 GC blocks. You could pull just the head off an 03+ TJ or GC I believe.
CF Veteran
Joined: Nov 2017
Posts: 3,700
Likes: 238
From: Groton, MA
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
Read Cruiser's post on engine swap:
https://www.cherokeeforum.com/f2/che...bility-236512/
Do you have the 331 head? If you only replaced the head gasket you might have missed that the problem is actually the head. See if replacing that will solve your problems.
How much metal is there? Where is it from? Or why is fuel in there? What does the drained oil look like? IIWY I'd try to get a better handle on that before I went into catastrophe mode.
https://www.cherokeeforum.com/f2/che...bility-236512/
Do you have the 331 head? If you only replaced the head gasket you might have missed that the problem is actually the head. See if replacing that will solve your problems.
How much metal is there? Where is it from? Or why is fuel in there? What does the drained oil look like? IIWY I'd try to get a better handle on that before I went into catastrophe mode.
O.P. It would be wise to provide your location. There may be a member that's physically close to you that might be willing to help you with the project. Having a shop replace the engine will be costly. You're looking at something in the thousands of dollars just for labor alone. The work isn't complicated, it's just there's a lot of it. If you have a good set of tools, a week of free time, a competent assistant and a means to lift the engine (Harbor Freight sells a shop crane for under $200), you don't need to be a professional mechanic.
If your block is OK, then you're in much better shape - a head replacement is less than half the work and doesn't require lifting the 500+ lb engine assembly into and out of the vehicle. The problem is that coolant or fuel in the oil is REALLY hard on the crankshaft bearings among other parts, so it doesn't take a lot of driving with that stuff in the oil to ruin the engine as a whole.
Thread Starter
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Year: 2000
Model: Cherokee (XJ)
Engine: 4.0L
Hey Pat (and everyone else), thanks for the info.
I'm in the Tuscaloosa, Alabama area. I would certainly be down to do this myself, as long as I have someone there to help me. I am currently a college student so my next period of free time would be the second week of May, after classes end and before internships start.
How would I determine what can be salvaged? I was debating bringing it into the shop for a diagnosis but I don't even know if they'll be able to tell much, or they'll probably just tell me i should go ahead and swap it. Can the problem of low oil pressure be solved without replacing the block?
I'm in the Tuscaloosa, Alabama area. I would certainly be down to do this myself, as long as I have someone there to help me. I am currently a college student so my next period of free time would be the second week of May, after classes end and before internships start.
How would I determine what can be salvaged? I was debating bringing it into the shop for a diagnosis but I don't even know if they'll be able to tell much, or they'll probably just tell me i should go ahead and swap it. Can the problem of low oil pressure be solved without replacing the block?
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Thread Starter
Junior Member
Joined: Jan 2019
Posts: 33
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Year: 2000
Model: Cherokee (XJ)
Engine: 4.0L
Also, I recently got a part time job at O'Reilly's to help get extra cash (and knowledge) for basic maintenance (I applied before I knew of the engine problems, which are a little more than basic maintenance). Looking through the computer, I see that I can get re-manufactured 4.0's for less than two grand. Would this be the route to go if I do need a replacement? Half the crap we sell looks so cheap I'd imagine "re-manufactured" just means "will fall apart in two years". Does anybody have experience with these parts?
I could get a 1999 XJ 4.0L with the better head and see if I (or the shop, we'll decide later) can make the adjustments needed to make it fit (new motor mounts, etc) that way I'm not stuck with the bad 0331 head like the 2000 model.
But then again, at that price, I can get a brand new aftermarket 4.0, but then I don't know if the reliability is the same as the OE engine. I plan to keep this car for as long I can and if i swap it once, I want it to last a long long time. Thanks again for everyone's responses!
I could get a 1999 XJ 4.0L with the better head and see if I (or the shop, we'll decide later) can make the adjustments needed to make it fit (new motor mounts, etc) that way I'm not stuck with the bad 0331 head like the 2000 model.
But then again, at that price, I can get a brand new aftermarket 4.0, but then I don't know if the reliability is the same as the OE engine. I plan to keep this car for as long I can and if i swap it once, I want it to last a long long time. Thanks again for everyone's responses!
CF Veteran
Joined: Nov 2017
Posts: 3,700
Likes: 238
From: Groton, MA
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
The rebuilt engines are varied in terms of quality, AFAIK the one brand to avoid is Jasper (due to the fact they do the bare minimum needed which can mean mismatched part sizes. Most if not all will have a warranty of some kind - just make sure that the terms are right (for example - does it need to be installed by a certified installer sort of thing.)
If you have low oil pressure (and to be clear, min spec is 13psi at "hot idle" - 75psi max) that's a bad sign for the low end (aka block side). Typical pressure is no lower than 20 when hot idle and 60-ish under load. The oil pressure is generated by the crank bearing/crank relationship, and crank bearing failure is typical when the engine has been run too long with fuel or coolant in it.
There are diffs between the manifolds such that a non-0331 style head is not directly compatible with prior years, I can't recall what the strategy is to mate your existing manifolds to the older head types, but the info is available if you Google it.
One possibility may be to get a good, low mileage block from a junkyard and put a clearwater head on it since the blocks are interchangeable across the years. Obviously this is less reliable than a rebuild, but would bring the replacement cost closer to 1k-ish.
If your oil pressure is really bad - just replace the engine - there's nothing that will restore pressure short of a rebuild. if it's close, you can drop the oil pan and pull a bearing cap to check the condition, but it's a fair amount of work.
If you have low oil pressure (and to be clear, min spec is 13psi at "hot idle" - 75psi max) that's a bad sign for the low end (aka block side). Typical pressure is no lower than 20 when hot idle and 60-ish under load. The oil pressure is generated by the crank bearing/crank relationship, and crank bearing failure is typical when the engine has been run too long with fuel or coolant in it.
There are diffs between the manifolds such that a non-0331 style head is not directly compatible with prior years, I can't recall what the strategy is to mate your existing manifolds to the older head types, but the info is available if you Google it.
One possibility may be to get a good, low mileage block from a junkyard and put a clearwater head on it since the blocks are interchangeable across the years. Obviously this is less reliable than a rebuild, but would bring the replacement cost closer to 1k-ish.
If your oil pressure is really bad - just replace the engine - there's nothing that will restore pressure short of a rebuild. if it's close, you can drop the oil pan and pull a bearing cap to check the condition, but it's a fair amount of work.
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Joined: Jan 2017
Posts: 3,402
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From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
I may have missed a post. Are you basing your decision of replacing the engine on the Blackstone report? Can you post that? Based on your previous comments if you had oil with 107,000 miles and a blown head gasket and only a half-hearted oil change that Blackstone report could be normal. And the oil pressure sensor could be full of sludge and inaccurate. Do you in fact have an 0331 head on there? And is it bad?
I recently purchased a 1996 2 door Cherokee 4.0 automatic tranny with 138k miles on the engine.... As I type this, a two-owner west coast automobile is on its way to Virginia. Any assistance in advance would be greatly appreciated.
I recently purchased a 1996 2 door Cherokee 4.0 automatic tranny with 138k miles on the engine.... As I type this, a two-owner west coast automobile is on its way to Virginia. Any assistance in advance would be greatly appreciated.
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Joined: Jan 2017
Posts: 3,402
Likes: 394
From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
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