How many miles to seat rings?

[william]

I have a 2.2TII engine with about 30 miles on it since a re-ring. It had less than 20k miles since a hone job, so there was still crosshatching in the cylinders, but it did not get a hone when the rings & pistons were replaced. I have good compression across all cylinders, but two are oiling (plugs 1 & 3 oily, oil in tailpipe). It smokes alot on decel, not so much under boost, and there doesn't seem to be any blow by. Car runs well.
Every other engine I have built did not require lengthy break-ins, and didn't smoke after the first couple miles. This was my first attempt at a real "half-assed" job, so I am not sure what to expect. Do I need to drive this another couple hundred miles? Any miracle tips to help those oil rings take a seat? My inclination is to pull the engine, but I'd hate to do that if it only needs to be driven some more. Thanks...

[22dodge]

Quote:

Originally Posted by william I have a 2.2TII engine with about 30 miles on it since a re-ring. It had less than 20k miles since a hone job, so there was still crosshatching in the cylinders, but it did not get a hone when the rings & pistons were replaced. I have good compression across all cylinders, but two are oiling (plugs 1 & 3 oily, oil in tailpipe). It smokes alot on decel, not so much under boost, and there doesn't seem to be any blow by. Car runs well. Every other engine I have built did not require lengthy break-ins, and didn't smoke after the first couple miles. This was my first attempt at a real "half-assed" job, so I am not sure what to expect. Do I need to drive this another couple hundred miles? Any miracle tips to help those oil rings take a seat? My inclination is to pull the engine, but I'd hate to do that if it only needs to be driven some more. Thanks...

need to do the job right. why do you think engine rebuilders have $20,000+ into just a honing machine.

even though you see crosshatching, it is imperative that the cylinder are deglazed.

additionally, is there any chance you improperly installed the rings or damaged the rings on installation? I've rebuilt a lot of engines over the years and sometimes I damage the oil ring, when I'm not paying attention.

[speeduphoria]

you should not have oiling probs if the cylinders and rings are in good shape, I had slight smoking upon startup and no oil consumption at all from the get go(new parts and machine work).

The rings should be seated in 30miles as long as you beat on it so they are forced to take the shape of the cylinder and there was a rough surface to wear them.

The other thing to look at is your PCV setup to see if thats working properly, and do a compression test as well

[kermit]

Doing a so called "half assed" job can still produce good results. You should have deglazed the cylinders with a hone...especially since you can rent one from Autozone for free, but I'm not sure that's your problem.

Oil burning on decel is typically a sign of valve wear. How did the engine run before the rering. You may need new valve guides or valve seals.

[william]

The engine ran very well before I melted a piston. The head was a recent rebuild, and the valve seals were still soft and in place. I actually own a hone, so I wouldn't have even needed to rent one, but the circumstances of the job did not allow for us to use it. I'm not sure this is a honing related problem either where it is only 2 of the 4.

I wasn't sure if a long seating period was typical of a no-hone re-ring, so I wanted to get some feedback from people who have done it. No question that when done correctly, there should be no such issues.

[22dodge]

Quote:

Originally Posted by william The engine ran very well before I melted a piston. The head was a recent rebuild, and the valve seals were still soft and in place. I actually own a hone, so I wouldn't have even needed to rent one, but the circumstances of the job did not allow for us to use it. I'm not sure this is a honing related problem either where it is only 2 of the 4. I wasn't sure if a long seating period was typical of a no-hone re-ring, so I wanted to get some feedback from people who have done it. No question that when done correctly, there should be no such issues.

did you reuse old rings?

so your saying the absolutely no way you could have installed a compression ring upsidedown, messed up an oil ring on assembly, had the expander overlap accidently, lined up the gaps, or made any other possible human error on assembly you are definitely the best mechanic out there.. except you didn't do an absolute necessity, deglazing the cylinders.

when I re-ring and engine (or rebuild), my rings seat immediately. even moly rings. ring sealing has a lot do do with type of ring material and surface finish. I use a Van Norman hone, followed by a bead hone then a Platteau brush to achieve the correct finish.

[william]

Quote:

Originally Posted by 22dodge did you reuse old rings? so your saying the absolutely no way you could have installed a compression ring upsidedown, messed up an oil ring on assembly, had the expander overlap accidently, lined up the gaps, or made any other possible human error on assembly you are definitely the best mechanic out there.. except you didn't do an absolute necessity, deglazing the cylinders. when I re-ring and engine (or rebuild), my rings seat immediately. even moly rings. ring sealing has a lot do do with type of ring material and surface finish. I use a Van Norman hone, followed by a bead hone then a Platteau brush to achieve the correct finish.

You may have misunderstood me. I think it is MORE likely an assembly error or damage, rather than the honing. If it was related to honing I would expect to see varying compression numbers, and oiling more consistently over all 4 cylinders. The fact that two cylinders are oiling heavily, and two not at all lends itself to ring damage or assembly error. Oh, yes, used rings of course; but they were the lowest mile rings I had in the garage!

I suppose I would be the best mechanic out there had that been by chosen vocation, but alas, I would only qualify as the best "untrained, amateur engine assembler".

[22dodge]

no misunderstanding, you said in the end of post "No question that when done correctly, there should be no such issues."

your problem lies in everything you told us. used rings, no honing, plus there's always the possiblilty of assembly error, like upside down compression ring

[william]

Quote:

Originally Posted by 22dodge no misunderstanding, you said in the end of post "No question that when done correctly, there should be no such issues." your problem lies in everything you told us. used rings, no honing, plus there's always the possiblilty of assembly error, like upside down compression ring

There is just *no* joy in this place.

[speeduphoria]

re using old rings is most likely your problem

[william]

Quote:

Originally Posted by speeduphoria re using old rings is most likely your problem

The pistons & rings had less than 2 hours on them, but after one stroke, used is used. I know lots of folks have done similar re-ring jobs, I was hoping to hear from one of them whether their experiences were similar.

[allmotor]

Quote:

Originally Posted by william The pistons & rings had less than 2 hours on them, but after one stroke, used is used. I know lots of folks have done similar re-ring jobs, I was hoping to hear from one of them whether their experiences were similar.

i did it on a 2300 pinto motor but i deglazed the cyl walls and used some krokus cloth on the rings to deglaze them to i also made sure the rings went on the right way so i didnt mix up top vs 2nd comp ring double checked gap location and oil rings were rite on the expanders motor ran great made power used no oil or smoked and had even pressure at 210 psi

[ol"blue]

I'm curious of a few things. How many & which cylinders had the melted pistons? Did you replace all, or just the bad pistons? Any chance you were given difference size pistons? Did you check the ring end-gaps. Did you replace the head gasket? What does the compression read now?

[phantomrt]

There are too many variables for me to sit here at the computer and guess what could be wrong, but it really does sound like a piston ring issue. I'm guessing the oil rings aren't scraping the oil back down the cylinder. Another thing to consider is how out-of-round were those cylinders? A round piston ring in an oval hole..??? ya never know until its checked.

I've had good luck with marking the position of piston ring gaps, removing/swapping out a piston, and re-using the old rings so that the gap is exactly where it was before. So far, never had a problem. No glaze breaking or anything and it worked perfectly. A couple of the engines I've gone through had some very questionable cylinder walls--pretty beat up actually, and they ran like a million bucks with just a glaze break job and new rings. Even the cheapest person on this forum probably wouldn't have gone with those cylinder walls, but I did it for personal education. It worked awesomely. No abnormal blow-by, great compression, no oil consumption, and lasted me 15,000 miles until I sold it. And I beat the snot out of that thing.

Not good to make this a habit, but as long as the rings are installed correctly, things work well.

[william]

It was only piston #1 that melted. It was down about 30 psi on a compression test. I replaced the pistons and rings as a set in all 4 cylinders (new HG as well), they had been pulled from an engine that had been run for an hour or so. I don't know why they were pulled, as it wasn't my engine. The whole thing was only meant to be a temporary fix, but I started to wonder if they might seat after a few more miles and I could run out the next few months as-is until the new engine is finished. No harm in trying I suppose, the black flies are getting bad in the neighbourhood anyway.