Tried searching for info on a 2002 GC 4.7L HO engine.
I just bought my fourth Jeep, a 2002 Grand Cherokee with spun main bearings. I did NOT know it was a two-piece block. So, which direction should I go? Try getting it line bored, get a built short block or a used complete engine.
Thanks for any insight.

 

Hmmm, news to me. I have a 99 4.7. I think I need to take a good look at that

 

Line boring is going to cost you....a lot! Better to get a rebuilt shortblock. A used engine is a compromise because you have no idea what kind of maintenance it's had. Those things don't take kindly to abuse.

 

Thanks, are there multiple year, models that will interchange?

 

All I can tell you is when I bought a rebuilt shortblock for my 4.0, the rebuilder wanted my block number to match the new block to, which means to me they don't want to sell you anything other than what you already have because of the warranty. I was looking for a 2002 or newer complete engine to replace my 2000 with the 0331 head and they wouldn't do it. That's why I went with a shortblock and used my Clearwater head.

Make sure the cam bearings in your heads haven't been compromised if it lost oil pressure enough to spin the lower end bearings. I've been told the cams run directly on the aluminum and when the heads warp, they wipe out the cam bearing also. IDK for sure. I DO know that if a cam jumps the chain, that whole bank is toast! The 4.7 and 3.7 are just too finicky for my tastes.

I grew up with the Chevy smallblock. You could put one of those together with junk parts and win races with it!

 

dave1123
Thanks. I just bought this Jeep for $450 with the engine in the back already disassembled. Its leather, all power and a sun roof.
Will it be worth installing a rebuilt engine or resell it as is? I was looking for a Jeep for my grandson who will start driving in the fall.
But, if I fix this one I might just start driving it.

Thanks for all the insight!!

 

There's a whole bunch of V8 WJs out there that you can get cheap because the engine puked. I heard a story where one guy stopped to help someone by the side of the road and the owner handed him the keys and said he could have the title if he would take him and his family to the nearest car rental shop! Usually when something goes wrong with a 4.7, it's expensive to fix. Yes, if you replace the engine you will have a great jeep, but it may be more than you want to spend to get it fixed. Your call. If they are maintained properly, they are a good engine, but too many people don't want to be bothered. Too many people just want to put gas in it and drive it....until something breaks.

 

OK! I just ordered a rebuilt 4.7 from Powertrain Products. SSSOooooo, since I bought this Jeep with the engine in pieces in the back; I have no idea of how or what needs to be done in what order.
I have been watching YouTube to make the install easy as it should. Can I install the intake/exhaust before I install the engine or after?