found my engine knock

[bmohan55]

A while back my engine suddenly developed a knocking sound that we all thought was a spun bearing. Finally got around to working in it and found that the top piston ring on #1 cylinder was missing and a piece of it was embedded in the #4 cylinder! In all the threads I've read on here I don't recall having seen this, any ideas how or why this happened?

We found lots of blow-by on all cylinders and a very leaky rear main seal so it was time for a re-build anyways. Had to re-bore to 30 over, but she looks so pretty now.

Amazingly I thought she was running pretty good up to that point!

A friend is doing the re-build with me "helping", quite a learning experience!

[LaneRover]

That shore is purty!

[I Leak Oil]

With high mileage the rings and ring grooves can wear out. Because of the wear in the groove, when a ring cracks part of it can roll over and find it's way to the top of the piston. You should feel blessed. I don't think it's very common.

[Moose]

I've seen that happen twice before. Once on my 2.25 petrol and then once on my buddies 2.25 diesel. This was over 20 years ago. Made a bit of a mess on my engine resulting in a rebuild with 30 over pistons as well.

Brett

[superstator]

Wait, you're saying the ring broke on #1, and migrated over to #4 somehow? Or am I misreading?

[I Leak Oil]

Ooo....I didn't pick up on that. That would be pretty rare for the ring to go from #1 to #4!

[bmohan55]

yep, thats what happened, #1 was missing it's top ring, #4 (pictured) still had all it's rings with parts of a ring (we found two large pieces in the oil pan) embeded in it.

[superstator]

Wow. Have you considered buying a couple lotto tickets?

[Moose]

Well, I misread that too. On ours the ring bits came up the side and embedded in the top of their own pistons.

Yours may very well be a first. Congrates!

Brett