Best reman 4.0's out there? Need a new engine!! -
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Unread 08-06-2013, 09:12 PM   #1
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1987 FSJ Wagoneer 
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Best reman 4.0's out there? Need a new engine!!

Well, after figuring I am going to keep this 98' Cherokee, I need to find a good, dependable reman 4.0. I have a blown head gasket, has 145,000 on the engine. Don't think the last owners really took care of it too well! I figure why have a new head and the bottom has 145,000? My mechanic thinks the rings will need work anyway. It looks like the previous owners (who own a BIG auto repair and used car sales place) just threw on a new head gasket to sell the thing. I knew it ran a bit rough, I just figured it needed injectors or a tune up. Drove ok back home. I have also put about 6,000 miles on it. The timing chain needs to be replaced. Now the head is leaking, sometimes white smoke out of the tailpipe when cold happens. Has a cracked exhaust manifold.It's running around 210-215 degrees in traffic and it's not that warm out here in Monterey, like 58-65 degrees in the day. Any GOOD places out there with a decent warranty and price is what I need!

Last edited by 56Mercgal; 08-06-2013 at 09:17 PM.. Reason: more words needed
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Unread 08-07-2013, 03:43 PM   #2
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A 4.0 block with that mileage wouldn't scare me at all. I'd put a new head if the head is trashed, but you might be able to fix it with a correctly replaced head gasket
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Unread 08-07-2013, 04:44 PM   #3
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Unless the Jeep has had minimal maintenance done to it (or it was driven for a prolonged period with coolant in oil due to a bad head gasket or cracked head), I highly doubt the piston rings are bad. I've seen multiple unopened 4.0 engines with 250 000+ miles with perfect compressions on every cylinder. It's not uncommon to see these things reach over 300k miles with regular oil changes and tune ups and still check good in smog tests and have decent compressions.

Go get the head tested/ measured at a machine shop if it has leaks or not. If no leaks, get the bottom shaved straight, valve seats and stems done, get a new head gasket, new intake/ exhaust manifold gaskets, new header (you're gonna need one anyways), and enjoy another 145k miles of life from your engine if the piston rings are ok.
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Unread 08-07-2013, 05:13 PM   #4
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Hi! Thanks for the reply! I had the cylinders tested a while back. and I remember it fluctuated a bit, not major bad. I am concerned coolant may have gone down into the bottom end. If that happened, i would HAVE to invest in a new engine. I have been hearing conflicting reports about ATK engines, and I have searched for other reman engine sources. All seem to have the same warranty, but then they have complaints. Not sure which way to turn here. It will cost me $2500 to have it rebuilt here, but the shop is excellent at rebuilding engines. The guy there rebuilt my 56' Mercury's 312
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Unread 08-09-2013, 10:34 PM   #5
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You could also go the junkyard route and take your sweet time rebuilding your current engine...that's my plan if/when the time comes.
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