The black stuff is hard. It burns like plastic? The small brownish pieces look like 3 bond or case sealant? Its rubbery. The black pieces are literally melted? into the oil filter. The other black pieces pictured in the block when the oil filter was removed are also hard. If it was a can am v twin I would say the plastic water pump gear or melted chain guides but not sure here. I can say the engine is much quieter now and seems to run ok. It just may be possible that this was the original oil filter. Customer owned since new and does not know when the oil was last changed.Doesn't look good at all. I would want to see what the crank case looks like. Is it solid/hard or soft/mushy?
What is in the red circle? Its brown looking.
I would flush the engine at least before I ran it. Maybe ask the customer if they have ever changed the oil since 2007
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Very well could be. This is a very used machine. Not much maintenance done. It should be ok now, Its on its second oil change since 2007 lolCan’t imagine it being plastic….as said, think your looking at 2007 model cooked oil and debris.
unless of course he’s forgetting to remove the oil from the plastic containers before putting into engine.