Rings.. and things.

I have a question. I believe I already know the answer. I just want to see what you guys can tell me.

A few years ago i rebuilt a XR200. It had some major engine damage from being ran without oil. I bought it super cheap. Anyway. I had the cylinder bored by a local shop and I replaced the crank bearings, rod bearing, rod, crankpin... and other things.. you get the picture. Of course i put a new pison and rings in it. I checked everything in the head out and it was all fine. After the rebuild it fired right up and ran great. It was smoking a little but being that i had just worked on it I wasn't worried too much. I ran the engine just like recommended for break in. It was still smoking. So I rode it a little longer and it just kept getting worse. So i pulled the engine out and pulled the top end off again. I found a couple of things that concerned me and I took the top end to the shop that worked on it to ask questions... Minus the piston and rings. I was told that i had installed the rings upside down. Now I know that i didn't. There was some damaged looking areas in the cylinder. I believe it was the shop that did something wrong when they bored the cylinder. Now my main question is.... what would happen if I did put the rings in upside down? What I mean mostly is what would it have done to the engine damage wise if anything. Explain what I would see if there was anything that would be obviously noticeable. Once I hear a couple of replies I will tell you all exactly what I found and why I think it was their fault. Please let me know.:thumbsup:

What was your piston clearance and ring gap?

Its been too long to remember exactly but it was in spec to the manual. Oh and I had about 10 years experience doing this type of work when I did this engine so I do know what I was doing. Its just that I had never heard anyone ever tell me what they told me.. Anyway like I said. I know what i did was right. I just want to know if I did what they said I did what would happen. I don't know since it is something I have never done. ( putting the rings in upside down i mean )

In a 4 stroke lack of sealing is about all I can imagine going haywire, in a 2t you might be able to hook a port in the extreme circumstances.

I suppose they could say it kept oil from the oil ring and that caused it. If it were in my shop I would measure the gap.

It is pretty hard for them to screw up to the point of damage if you checked the bore. It could have been out of square, but that would have shown up too.

I wish i would have taken pictures back then. What i found when i took it apart was gouges in the cylinder.... but not lengthwise( up and down ) . They ran around the bore. I looked at it before I put it together but when they honed it it must have kind of disguised it. They weren't very deep. Being a tool maker and a machinist for several years they looked like gouges caused by an issue with the boring tools. I really believe that is what it was. Like you all I could see happening from them being upside down is issues with sealing and such. I mean if the gouges were up and down... maybe i would have bought it be it true or not.

They might have left boring marks. I know when I was boring cylinders I would bore to size, then hone for fit. That way the boring marks would be erased.

Even if the problem was the rings upside down, you could just merely flip them over and run it again. As far as I remember the second ring is really the only directional one. The upper ring would not cause oil burning if upside down.

Few questions

Was the oil ring expanded overlapping itself?

What condition was cylinder head in? Valves, seals, etc

I'm just curious as to the issue being caused by the head or the piston and rings.

What did the jug damage look like? Pics?

There was absolutely nothing wrong with anything. other than a few nicks in the head from debris. Everything with the valves was perfectly fine. The engine had pretty low hours before it was ran low on oil. I don't know how it ended up low. Everything in the head was fine though. And I explained the damage in a earlier post.

The rings were fine on mine. I know it was something they did. I just wanted some reassurance. The groves they left were bad. You could really see them after I had taken it back apart since it wouldn't quit smoking. I ended up in a huge argument with the service people at the local shop. This wasn't the first time I had had problems with them. I have not set foot in the place since. We only have a couple of local shops around so it kind of sucked getting parts. Thank god the internet is more popular now than it was back then. I really have little use for a shop now. I have a good place to have machine work done now that I have had zero problems with. At the time that this all happened I did not have a very good job and was tight on cash. Having just spent quite a bit doing what I had done I really didn't have a lot of options. So I took a cylinder hone that i had and honed the cylinder till the marks were about as gone as I could get them without going way too far. It was a little out of spec and there were still some gouges but not too bad. I put it back together and I am still riding it to this day. It smokes a little but not anything like it did. One day I will likely do something with it but for now its a good back up when my regular bike is down.

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