The before/after on a Cessna 172 cylinder change I did last month blew my mind

I swapped a jug on a 172 that had 1,200 hours and was burning a quart every 3 hours. After the new cylinder and piston rings broke in over 10 flight hours, oil consumption dropped to less than a quart every 10 hours. The old jug had so much scoring on the barrel walls I could feel it with my fingernail. Anyone else seen a worn cylinder go from looking fine to that bad so fast?

2 comments

2 Comments

torres.drew11d ago

Check the oil return holes on that old jug, they love to get carboned up and starve the top end before you even see big wear numbers coming through.

mila_mitchell10d ago

Starve the top end before you even see big wear numbers" - that's exactly the kind of sneaky failure that catches you off guard. You ever seen those return holes get so packed with carbon that it's basically solid? I'm guessing you'd have to pull the top end to really clean em out proper, not just a quick spray job.