[Guest]

I've got a 94 ZJ, 5.2L V8, 125K miles. Just got the news from the mechanic that 3 cylinders on one side don't have any compression, he said I need to replace my motor. He's probably right but are there any other options? Can I have the rings replaced on that side or new piston/rings? Has anyone replaced an engine, how hard is it?

As far as engine replacement goes, I got a quote from a junkyard for $1,000 for a motor, not installed. Chrysler wants $3200 for a rebuilt, not installed. I checked what my jeep is worth and it's about $5000. Hardly worth it to go buy a new motor.

Any info on cost effective options would be greatly appreciated. Right now I'm sort of starting to gather information on what my best options are.

Thanks,

Curtis Lloyd

 

[3181]

Well, it tough to say based on your post. Unless you know more of the details and trust this mechanic, then I would go get a second opinion. Thats the first thing I would do. I realize a lot of people say this, but I was almost screwed out of a large quantity of money on the wifes Jetta. Luckily I got the hint that these people were morons, took it somewhere else, and got the real story on my low compression.

Anywho, lets just say that you do need a new motor. Your two option are:

1. Find a competent engine machine shop and get an estimate rebuilding your current engine.

2. Just replace the engine as you mentioned, with either a factory rebuild or a *used* engine as you have already researched.

Lastly, as for pulling a motor and putting a new one in... I have done this on an old Chevy 400 and soon a '49 Ford f-1, but no jeeps. It is my opinioin that if you are the type of person that does all the "usual" work on your jeep, and you have a fairly good understanding of whats happening under the hood then you can pull and replace an engine. I would research it, try and find people that have pulled the 5.2 (as your doing right now) and you will know whether or not your up for the task.

What im getting at... is pulling an engine hard? I feel that completely depends on your mechanical experience, knowledge of your jeep, knowledgable freinds, and how much beer is consumed during the project.

Hope that helps and hopefully someone who has yanked a jeep motor will chime in.

-jm

 

[Guest]

i have changed the engine in my xj.the only info i can give you is to mark all you plug-ins.

 

[NIX]

Some things to consider: What's the value of your grand with this engine? 2 grand? Less? Then a rebuilt engine is an option. At least you know the rest of this car. You never know what you get if you decide to go out and spend 5 grand for another Jeep. A new engine or one with less milage is also an upgrade for your jeep.

New rings only are an option if it's only the rings that cause the problem. First find out if the valves and head are OK. If it's only rings and the cilinders don't show serious wear, don't forget to hone the cilinders for proper breaking in. Remember that taking an engine apart very often leads to unexpected other defects. While it is apart, why not replace bearings, rebuild the heads etc....

 

[stump_breaker]

My 2 cents here........
First, get a second opinion or get a compression gauge and check it yourself. Remember KISS..........not your mechanic, that means keep it simple stupid. Start small before you go to tearing into stuff. Try a can of CD2 Restore, it could give you a few more miles in the old engine.

Pulling an engine is not hard if:
1. You have some mechanical aptitude
2. You have patience and time and a buddy with beer
3. You have a Chiltion's or a Haynes or other similar book
4. You have the RIGHT tools and a Cherry Picker (Engine Hoist to you Northern boys). A tree limb, a chain and a come-a-long is just asking for trouble although alot of us have been there (raising hand on this one).

Nothing sucks worse than to spend 3 days trying to get a doohickey off a thingamabob then to find out that there was a special discombobulator at the parts store that could have it off in 20 minutes.

I've never done a Jeep engine but I have done several 350 pulls, rebuilds, and intsalls and one 4 cylinder turbo Chrysler Lebarron convertible (that was a waste of time - twice!). I got to where I could have a 350 out of a Camaro in about 1 1/2 hours by myself. If you go to a motor shop ask for a long block rebuild. They might have one there for you with a core exchange. One on a 2.8 cost me less than $500 bucks and came with a 12 month/12,000 mile warranty and here it is 30,000 miles later and still running strong - or as strong as a 2.8 can be anyway. Then take the heads and have them vatted and worked. If you do it right and do the labor yourself you could spend less than 1500 to 2000 dollars (maybe less)and have a very stong motor. While your in the engine beef it up a little - cam, roller rockers, etc. Not sure on the Jeep V-8 but you should be able to find kits that can give you the HP or Torque ranges you want. I had someone do it all for me in the old '86 - I just got the big parts and brought it to him - and spent $1700 here in Dallas. If you rebuild yourself, don't halfa$$ it. Replace all the internal parts. New parts mixed with old parts will cause the old parts to wear faster from the increased stress and you will be right back to where you are now. There is some sort of name for this but I can never remember it.

Only one other thing to say, GOOD LUCK!!

 

[NCXJ]

on a side note, i saw a 5.2 engine sitting on the crate fixing to be sent to jasper last week at the dealership. two connecting rods flew out the oil pan. under the intake, there was so much "crud" acculmilation, you couldn't even see the push rods.
anyway, you might be able to find a junk 5.2 in a yard that would be cheaper than a rebuild. although they're not as plentiful as our 4.0's!

 

[Guest]

I would get a second opinion on the engine. 5.2L usually last longer than 125000 miles unless you haven,t been changing your oil regularly enough. Did you mechanic do a cylinder leak down test or just a compression test. A compression test by it self is useless because it doesnt tell you where the compression is going. A leak down test will let you know if you have bad rings,burnt valves or a blown head gasket. If the rings are ok and you had good oil pressure then just fix the the cause of the lost compression. I have 193000 miles on my 95 grand Cherokee and it still runs good. If your motor is bad you should be able to pick up a used one fairly cheap. just look down the valve cover to make sure the person who had it was changing their oil.

 

[Guest]

One thing to consider if you go the junk yard engine route and that is that most junk yards only garantee that an engine won't knock. You could be buying some one elses problem by going this route.