The International Cessna^® 170 Association

It’s annual time and as usual I’m chasing oil leaks (aren’t we all). I suspect my #2 cylinder valve cover may be leaking so I’ve removed it with the plan to replace the gasket with a spare one I have on hand. This is the first time this valve cover has been removed since my major oh in 1999, something over 1200 hrs ago. The spare one p# is AEC530162-063S which seems to be the one (Real gasket) AS shows fits my engine. The one I have removed has no p# or any other data, but I’m guessing it may be a Real mfg also as it’s the same color and appears to be made of the same material. This is where the similarities end. The spare one is flat on both sides and is approximately 50% thinner than the one I removed. The one removed is flat on the back/cylinder side, but the valve cover side has a molded groove that the valve cover fits in. I’m concerned a thinner gasket may end up leaking more than the one removed. What is the proper way to proceed?

Are you sure that's a molded groove and not just where the rubber has compressed? You'd think silicone wouldn't take a set that way, but it seems to.

I'd install the new gasket. Worst case it seeps and you have to try again. Take the normal precautions of making sure the surfaces are completely clean and don't overtighten the screws.

Rereading some posts on this subject I see that I misspoke regarding how long my # 2 gasket had been on the engine. I see that back in 2012 I posted that I had replaced the gaskets that were installed at overhaul in '99 with Real gaskets "several yrs" ago. Sorry for the error.

merged topic w/original