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Hi all,
Next question on a P42 rebuild. I pulled the top end off last night and it seems something made it's way into the cylinder and is now mashed into the upper chamber (See image 1) Also corresponding damage to the top of the piston (See image 3). Cylinder bore still seems ok, some scoring on the exhaust side. Circlips are both in and accounted for...anybody have any ideas from where a part might break off and find it's way in?
Bits of a rod bearing cage?
Yep, rod bearing cage or main bearing cage material. Those saws had metal cages in the main bearings from the factory. One may have broken loose just from years of wear and tear.
They're definitely worth rebuilding - they're tough machines.