Sleeves Vs. Honing

When overhauling DIESELS , is it always best to replace sleeves (if there is no evident wear )/or can a guy get by with measuring and honing cylindars and putting in new rings ... ..Are Gassers more forgiving than diesels in regard to this Question ?..been a slow week ,.. so lets hear from the sidelines ...

I have never torn a diesel down that the sleeves didn't show signs of wear, so I always replace them. Every now and the I find a Ford that doesn't need boreing.Most of the time on diesels the pistons are worn out and you may as well buy the kit.

Yes, gassers are more forgiving as they run with lower compression ratios. The thing with honing is it takes away material. There is no way a honed cylinder can be as tight as a new one. And the object in overhauling an engine is to get it back to original specs. So yeah, if the cylinders show minimal wear you can hone the cylinders to break the glaze and put in new rings. It will probably be better than it was but will never be as good as it could have been.

This is just my opinion so don't jump all over me. Guess I spent too many years living out of a tool box.

Take the rings off the piston, put the piston back in the hole and measure the skirt to wall clearance.

It should be somewhere in the area of .0055". That's five and one-half thousandths of an inch.

If this clearance is excessive, the engine needs the whole smear. Pistons, rings, wrist pin bushings, sleeves, etc.

If, on the other hand, the clearance is okay, ya just tore the engine down for no good reason.

Again, and in my opinion, "ringing" an engine is a total waste of time because they NEVER, EVER last.

Kinda like "lapping" a valve. :>)

Allan

If the cylinder walls are mic'd and are within tolerable limits...by all means hone the cylinders and install new rings. You will get a few more years/miles/hours out of it. And, if your on the tight budget as to what you can and cannont invest in the equipment and a valve job and/or head rebuild doesn't fit into said budget...by all means, "lap" the valves in if the seats and the valve faces aren't totaly burned up.

This will not make the engine perform at it's peak ablility but will cure the oil consumption and poor performance for the short term. Lots of times, if the equipment requires repair, but is not used a lot this is a good solution to the problem both timewise and financially.

I agree with the other replies to this thread. I was raised up on and have lived on a tight budget for most of my young life. So many times, replacement costs of equipment and what could be spent on the repairs have driven the short cuts and the patches. I believe that whenever possible to make the performance the optimum is what needs to be done.

Best Of Luck with making your project productive to your needs.

If working a diesel, bore/cylinder wear is just one thing to consider. Many diesels have wet sleeves that get pitted something awful on the OD where they contact coolant. Basically, the higher the horsepower, the more apt to be pitted.
Also has something to do with wall thickness.

Also, when a diesel has bore wear, it just about always has top piston-ring groove wear and that tolerance is critical.

In answer to your specific question, if "no evident wear" actually means you inspect the OD and ID and all is pretty good - then yeah, you can reuse the sleeves. I've done a few that way, but it's pretty rare when that happens.

At the last Deere dealership I worked at, we had to pull apart many, almost new tractors - hone and re-ring without replacing any major parts. Why? Deere had a problem for awhile with rings being installed at the factory with all the gaps lined up instead of being staggered. It was causing excessive oil consumption. So, Deere advised that, if no abnormal wear or scoring was present, to just lightly put a new cross-hatch hone on the walls, install new rings with gaps 180 degrees apart and reassemble. Then load right away on a dyno to make the rings "set" and not walk around the pistons.

So, in those cases - we did it and it worked fine.

On a high-hour engine with a compression ratio 18 to 1 and maybe as high as 22 to 1 ? Things better be in awful good shape.

While were on the topic. I have the head off my JD 4020 diesel replacing a seeping head gasket.
With a dial bore gauge we measure 2.5 thousands out of round in the cylinders.What do you think of that? Tractor had a kit installed 3000 hours ago. Do not plan to ever part with tractor, but I only put about 60 hours a year on it.
So you know I am not a tight wad at this time I have had injection pump rebuilt,new injectors,head bolts,rocker arms and valves in the head. Mark

I'd say that's probably about normal wear for 3000 hours. I have torn down some smaller Deeres with 7000+ hours and found close to .010 in the top of the cyl.

Use new fasteners or the head gasket is going to seep again. Setting sleeve heights is also vital.