Merc 50hp 2-stroke advice
I have begun taking apart and rebuilding an engine for the first time. It’s an older (2003) Merc 50hp 2-Stroke. Before disassembling it had low compression across all cylinders (60-70 across all 3) verified with two separate compression gauges. I would start and run; however, seemed to have excessive oil in the exhaust and ran a little hot. The prior owner was not a real maintenance kinda guy and I don’t think the impeller was replaced often and I stupidly did not verify the oil injection pump was working before I disassembled the thing (too late now).
Split the block and didn’t notice anything super alarming like loose metal bits or anything. There appeared to be a little bit of very light discoloration on the surface of the block towards the first cylinder as well as discoloration on the pistons which I figured was a result of blow-by of exhaust gas (see photo). I have yet to measure the bore diameter but there was a bit of vertical scoring that was deep enough to catch a finger nail on in 2/3 cylinders.
As this is my first time I am really looking for any and all advice on next steps or reference materials to consult. Thanks!