Engine rebuild guidelines

[CessPooL]

Hello all.

I just bought a 90 YJ. 4.2 carbureted with AX15 trans. My daughter has wanted a jeep for awhile now, her boyfriend has one and i've been beaten into submission finally... This will be a christmas gift for her. The frame and body is solid, but it does have its fair share of issues. One being the syncros are going out in the trans i'm told. I don't feel any issues with driving it, and ill have to look into it more once I can get it out of hiding. But for 3k and being this clean, I was more than happy.

As stated, it has the 4.2. He has a new carb and electronic choke and it has no issues starting in cold. I guess the 4.2 is less desirable than the 4.0 and if I have to pull the trans to rebuild it i'm going to overhaul the engine as well. Really, my biggest qualm with the entire jeep is how dirty the engine bay is. Id love to pull everything and clean it up. With it out id like to look into putting the jeep MPI kit on it (I know, pricey) and with that it says the engine should be relatively fresh I'm seeing. Well if I have to overhaul the engine, might as well stroke it a bit eh?

I've been lurking these forums for a week or 2 now. Really, what I want is a nice procedure / guideline for tearing down one of these engine start to finish to read over. Not just "use these rods and that piston with the 4.0 head." etc etc with that said, what is the safest stroke if you will? not for crazy power, but more for reliability over anything. More torque would be nice for her (as i'm teaching her to drive a manual on this) and what would or would not work with the MPI kit? I don't care to put a 4.0 head on it and go to higher octane gas as long it doesn't compromise anything else or interfere with the MPI.

So is there a guide out there for a tear down / rebuild? And whats the right direction for a mild stroke with reliability on the forefront?

Thanks all!!

[Cheromaniac]

Stroker builds are based on the 4.0L block, and it's the larger bore cylinders of the 4.0L block combined with the longer stroke of the 4.2L crank that produces the extra displacement.
I suggest you look for a tired '91-'95 YJ to use as a parts donor (4.0L engine, wiring harness, ECU, MPI system, AX15 tranny) so that you'd have everything you'd need to start the project.