Paint flaking off cylinder barrel. Normal? Common?

[alpinelakespilot2000]

My 300-hr Aerosport Power 0-320 has a fair amount of black paint flaking off all four of the barrels, particularly on the flange that connects to the case. Is this common, normal, OK?

[Ironflight]

Well, I see it a lot......does that make it normal?

[Vlad]

Steve after my tach flipped first thousand hours about two years ago I worried about this. Factory baked Lycoming only three years in service?







Imagine now after recommended TBO? I don't even want to post a picture

[az_gila]

Originally Posted by Ironflight

Well, I see it a lot......does that make it normal?

You might see it a lot less now that you have moved to dry NV from wet Houston...

[flyboy1963]

'Normal' is for the engine to leak just enough oil to keep the metal parts from rusting!
It's a finely engineered Lycoming feature.....no extra charge!

[1001001]

My Warrior has a low-time O-320 rebuilt by Penn Yan. Same as Vlad's pic above. I was told by an A&P that it is very common and not to worry. Don't know if this is true but he said years ago a paint formulation change was made and flaking became common thereafter.

[Robert Anglin]

When we used to judge aircraft at the SWRFI, we quickly learned that paint was only worth a very small percent of a score. Translation= paint don't make them fly and better, just keeps them lasting a little longer. The last engine I built for myself, I spent a good amount of time prepping and painting with very good high temp engine paint. You guessed it, it flakes off too.
I know this dose not settle your concern but, this is why we work on them every week end, or so it seems. Yours as always, R.E.A. III #80888

[alpinelakespilot2000]

Thanks for the replies. As I understand it, paint on surface contacting the case would have been a no-no during the initial build, so there should be no paint to loosen there to reduce the torque on the nuts holding the cylinders to the case, right? That was my initial concern, though having to somehow try to keep the rust away is a bit of a concern.

That said, my Aerosport has always "weeped" oil from points unknown, so things usually get a pretty good "anti-rust" oil misting eventually.

[Robert Anglin]

Yes, if it is a factory engine they paint it after it is assembled. You are correct in, if you paint it as you go together with it, you want the flanges clean with no paint on the mating surfaces. It's not in the book, but you may want to hit that rust with a little corrosion-X from time to time. Most will rightfully tell you anything you put on the surface will change the heat exchange rate, but "I" have had good luck if this is not over done with my rust buckets.
Yours, R.E.A. III #80888

[Low Pass]

Originally Posted by Robert Anglin

Yes, if it is a factory engine they paint it after it is assembled. You are correct in, if you paint it as you go together with it, you want the flanges clean with no paint on the mating surfaces. It's not in the book, but you may want to hit that rust with a little corrosion-X from time to time. Most will rightfully tell you anything you put on the surface will change the heat exchange rate, but "I" have had good luck if this is not over done with my rust buckets.
Yours, R.E.A. III #80888

A 3 mil layer of coating like Corrosion X is less of an insulator than 10 mils of rust! Not to mention stopping the corrosion damage. Myth busted. I'm with you Robert. Steel parts get some protective coating on my plane when/if the paint fails.