partial 4.0 rebuild, what else do I need?

I'm going to do a partial rebuild on my 4.0 before driving it across the country again in 2 months (MI to CA). It's an '88 Renix with about 200k. This is pretty much my first experience with internal motor type stuff, but I have a couple experienced guys that will be available to me(not necesarily with Jeeps, just engine rebuilds in general).

Right now I'm looking at just getting rings, lower bearings, and all the gaskets. Do I really need anything else, or should I do anything else while I'm in there? I don't have the time or money for a full rebuild and just want to re-ring the pistons to get some of my compression back.

Thanks
Brett

oh, and does anyone know of any good online places to get these parts or should I go to a local NAPA or other autoparts store?

If you re-ring with boring/honing the cylinders, it won't be long at all before the cylinders are back to the state they were before the teardown.

At 200K miles, assuming the engine is running OK, has good oil pressure, and not burning oil like mad, I would leave it alone, or do the whole thing. Anything half-way will not result in a satisfactory result.

AZ Jeff said:

If you re-ring with boring/honing the cylinders, it won't be long at all before the cylinders are back to the state they were before the teardown.

At 200K miles, assuming the engine is running OK, has good oil pressure, and not burning oil like mad, I would leave it alone, or do the whole thing. Anything half-way will not result in a satisfactory result.

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I'd have to agree with AZ Jeff here. Why are you considering just a partial rebuild? Cost of parts for a full rebuild is not much more. Sounds like you are doing the labor on it. I'd leave it alone and take it easy on the trip if there are no big problems right now.

I usually end up buying my stock type parts locally, of course I tend to need those parts "like right now" so waiting for them to come through the mail wouldn't work.

MaXJ --

I'm going to have to pile on, too. At 200k, your cylinders may be worn slightly out of round, and if that's the case even with honing your new rings will probably seat and seal worse than what you have now.

I'm at 240,000 on my '88 XJ and I wouldn't hesitate to drive it across the country. What makes you think you need to do anything? What are your compression readings (hot and cold, and dry and then oiled)? What kind of oil pressure do you have at idle and on the highway?

If you have terrible oil pressure you might do rod bearings and an oil pump, but aside from that I think you should leave it alone.

hmm, I definitely respect the opinions here, so I will definitely reconsider. I think I just lost some rings because I started getting serious blow-by very suddenly, and the CCV lines are new and clear, valve cover cleaned out, etc. Anytime I spend more than an hour on the highway it starts spittin oil pretty good (not enough that I'm actually worried about the oil-level). I'm gonna check the compression tomorrow, I think my oil pressure sensor is screwed up because it reads pretty consistently between 60 and 80 ever since I swapped in the cluster with guages last year.

I would just hate to get halfway and have the whole thing take a crap on me, if I can do a $200, weekend rebuild that will just garauntee I will get it home running good, I'll do it.