Re-Ringing ?

[BMIC]

I have read references to "Re-Ringing" (most recently Modifications/Comanche-Country 12/9). My L-134 engine started and ran great. Oil pressure was consistant at about 40lbs and no over heating problems. I am planning on having it rebuilt because of oil leaks and heavy blue exhaust.
Is simply replacing the rings rather than a major overhaul a viable option? I am comfortable with doing a ring replacement, not a total overhaul.

It's a great life, working on my CJ3A weekends and reading the forum all week at work.....

[p3ferris]

I guess  I will give you a chance to decide yourself.  If you replace the rings, you will be takeing the rod bearings off.  That is the time to replace them.  If you have the rod bearings off the crank shaft has nothing on it so that is the time to change the crank bearings.  Oil pan is off anr the oil pump is access able as is the screen.  Oh the heads are off and how does the valves look.  Need reground?? Is the oil from the rings for sure or is the valve guides a little loose.  Well you have a decision to make.  Let us know what you decide.

[ventport]

When you have the head off grab an open valve and try to wiggle it sideways.  If it moves much at all you need valve guides.  Bad guides will cause it to burn oil and have blue smoke.

[F Bill]

Reringing is an option when cylinder wear is within limits..If you have a ring ridge chances are a rering will not last very long. Like was said above, an inframe valve cleanup and new rod inserts are pretty much standard practice when reringing  instead of a full machine shop rebuild.   At a minimum on the valves, removal , decarbonjing, and lapping in are worth doing now. if your pistons move around a bunch in their holes, a simple ring job will not cure it.

I guess it all depends on how quickly you can pop out your motor whether the time savings are worth versus having  have the complete job done. Do you have good sealing on the rear main or does it drip pretty good? Is your clutch good or on its last legs? Do you need to clean out your cooling passages in the block or has the engine been pretty well maintained and it still had solid freeze plugs, not ones that are starting to weep?

[Gunslinger]

Bmic,
Thats a lot of good advice, and none of it wrong in my opinion.  It really boils down to how you use your jeep and what your expectations are going forward.  I've re-ringed several old tractors without re-builds.  I got a way with that because I had good oil pressure to start with, so good bearings.  All were flat head motors and the valves were in acceptable condition.  They were acceptable because my expectations were that these were parade vehicles, no heavy work or long hours in the field.  All I wanted them to do was not smoke in the parade.  When it came to the jeep I took here down to the bones and re-built it because I want a reliable useable daily driver with some off road capability.

Decide what your going to use it for and build it from there.  If its about getting the most vehicle you can for the least amount of cash, maybe you gotta sneak up on some of the more costly stuff.

[Frank]

The Classic Poor Mans overhaul,

Re Ring, Yes as mention the Block Tapper and out of round determines the outcome of the re ring, Have to tear it down, take some measurements and then make the call,

[Carls_jeep]

If you consider to install new rings you will have to measure the bore. If the bore is .010" oversize or more new rings will not solve the problem. If the bore is near the .010" it may be a marginal repair. If the valves are loose in the valve guides they need replacing or reaming out and using oversize valves and grinding the seats. Since your oil pressure is about 40 lbs. the mains may be ok and you could use the old rod bearings but why not change the main and rod bearings now.

Does your rear seal or front seal leak. If not you may get by with using them over.

By the way, if you replace the main bearings only replace one bearing set at a time. Don't pull all the caps at one time. Rolling the upper shell in will be an interesting learning experience. I have done that many, many times.

Doing an in the chassis overhaul has issues. You have to consider the mileage on the engine. You say your "planning on having it rebuilt", does that mean someone else is doing it?

[Gunslinger]

Carl,
Correct me on this, but on the L134, I think the locking pin for the front bearing is in the block, not the cap, hence if you try to roll in the bearing you will become quite frustrated, unless someone removed it on previous build.

[Carls_jeep]

Since I have not had the crank out of one of these engines I don't know how the bearings are retained from spinning. I am assuming they have notches on the sides like rod bearings do. If that is the case you modify a bolt to fit in the oil hole in the crank and then turn the crank to roll the bearing out. If the bearing is pinned in the bore you would have to remove the crank to replace the bearings.

Are the bearing shells pinned in the block? If so that is a strange way to do it.

[Gunslinger]

On mine the front crank bearing is pinned in the block and the other two are pinned in the shells.  I have no idea why, but you are correct, its a goofy way to do it.