Cracked engine block, need help with replacement.

jchav74 · 07-01-2008, 12:22 PM

I found out yesterday that my jeep has a cracked engine block, near the freeze plugs. Looks like it may have been that way for a while. Is is difficult to track down a replacement engine? How much and is there anything else I should be looking for? Jeep is an 87' wangler with 4.2L. Thanks for the help.

heybubb · 07-01-2008, 12:24 PM

I have a 4.2 from an 89. PO says less than 30k miles, some paperwork to verify this. The head is blon, but rest should be good. Let me know if interested.

blokeontheend · 07-01-2008, 02:16 PM

www.Daveysjeeps.com has a $750 4.0L with low mileage. They're cheap because the mounting tabs are broken off and would need to be welded on.

**Leans93** · 07-01-2008, 02:35 PM

You may be able to track down a replacement engine at a salvage/junkyard. Also I see a lot of engines on Craigslist.

I just bought a remanufactured 4.0L engine from a local Phoenix engine shop. $999 with core. Since your block is cracked you probably would have to pay a core charge at an engine shop.

93jeepyj · 07-01-2008, 03:32 PM

how bad is the crack and how big? does the motor still run ok ? I've seen guys weld em before, just a thought

Ryanpowell167 · 07-01-2008, 05:50 PM

If its just in the water jacket and does not extend into, or cause a leak into the comb. chamber, you can weld it. Use a high nickel rod and dont get it too hot. This is something for an experienced welder to do...

4.7stroker · 07-01-2008, 09:35 PM

I would head down to the pick a part and buy a core engine to have rebuilt. i know they have a couple AMC Eagles with the 4.2 in them, they probably even have some Cherokees with the 4.2.
I have a good head here if needed
It should cost~150 for a core then take it to the machine shop up by car max, alameda/I25 Empire engines is their name, they will do a good job on a rebuild for you.
Or you could build a stroker, I can help you with that, it costs no more using your crank n rods + the 4.0 core it is fairly painless.

Dwayne

**Bgeddes** · 07-01-2008, 10:44 PM

Look around, I bought my beater YJ with a blown 4.2, and got a running motor for free, with an HEI!! I used the Weber that was on the blown unit and it runs like a top now. The engine was listed on a sort of local Jeep club website, and someone wanted it out of their garage.

I still have the block from the blown engine, but it's been outside for a couple years, stripped.

jchav74 · 07-02-2008, 12:33 PM

Thanks for all your replies. I think the crack is relatively small. The guy I took it to said it may have been this way for a while. I only recently started noticing fluid being dropped by the engine, which is why I took it in. If it is a weldable thing, where do I look to get it done? A regular mechanic, machine shop? I have been hesitant to put a lot more money into the jeep because it is getting to that point where it is having alot of reliablity issues (engine, tranny, suspension, etc...). I am either going to have to overhaul the entire jeep or trade it in for something newer. I don't have a lot time to do any major things myself.

1995_4.5L Jeep · 07-02-2008, 04:14 PM

Quote:

Originally Posted by 4.7stroker

Or you could build a stroker, I can help you with that, it costs no more using your crank n rods + the 4.0 core it is fairly painless.

Dwayne

4.0L blocks are everywhere! I did a poor man's sroker build and it was wicked cheap!
http://www.jeeperz-creeperz.com/fron...s-p-29960.html

4.7stroker · 07-02-2008, 05:42 PM

If it is that bad and you just want to nurse it buy some block sealer.
Follow the instructions.
Some of it is really good but you will have to read the instructions, some won't work if there is antifreeze in there.
So you must drain n flush fill with water add sealant let it seal then drain and add a 50/50 mix.
Go to Pep boys/napa/autozone etc and start reading till you find one you like the sound of.

Dwyne

4.7stroker · 07-02-2008, 05:45 PM

Look what I just found for you.

http://albuquerque.craigslist.org/pts/739992243.html

Dwayne

jchav74 · 07-02-2008, 09:32 PM

Nice. Thanks 4.7stroker. I am going to check into it. I have never bought anything from craigslist. Anything I should look out for?

4.7stroker · 07-03-2008, 09:10 AM

If you can see it running that is a big plus.
Give it a good look over, pull plugs, remove the valve cover if he will let you and look for crud.
Turn the motor over cw/ccw while watching the rotor arm, you are looking for slop in the timing chain.
Check compression if you can.
Normal stuff.

Dwayne

jchav74 · 07-03-2008, 10:17 AM

By the sound of it, he has already pulled the engine out.