Cylinder Preparation

crashr · 02-10-2003, 01:16 PM

I know there are tons of threads on this debated topic but I have a specific question to ask that I couldn't find an answer to.

I am bringing my cylinders & pistons (Mahle) to our home town Porsche Mechanic (trained By Porsche in Stuttgart). He took a look at my cylinders when I brought them by and he said they were like brand new. Anyways he said that you can't touch the cylinder walls with anything; this is contrary to what I have heard alot on this board. He was going to just put new rings on the pistons and pop them back in the cylinders. I have heard people say that if you don't rough up the surface you won't get decent compression. Is this true? Has anyone ever just put the rings back on the cylinders and had everything work fine.

On a second note, my mechanic was not pleased with the three peice oil ring that was on each piston and he seemed to think the one peice is the only way to go. Can anyone comment on this fact?

Thanks for all the help,
Dennis

Superman · 02-10-2003, 01:24 PM

I've never heard of a one piece oil ring. Compression rings, yes. Oil rings, no. The Goetze (German, I think) rings I put in my SC had at least two pieces to the oil ring.

Your mechanic is certainly correct about cylinder walls on Porsche cylinders. JW washed mine in his special BFPW (large parts washer), which took the glaze out of the business surface, but they were not touched at all except for that thorough cleaning. I think my rings might have had trouble seating if it had not been for that thorough cleaning. As it happened, the rings seated just fine. The engine did not smoke at all, and it burns no oil.

Your mechanic is correct.

crashr · 02-10-2003, 04:46 PM

I may have misunderstood him about how many peices made up the oil ring (thick german accent) but I know he didn't like the three peice one I had on there.

As far as cylinder prep goes; since my mechanic is saying my cylinder walls look like new, would this be why he isn't conserned about doing anything to them. I will ask him tomorrow but I like to know what I am talking about before I go talk to him.