Have a Honda BF75L ser#1700344 . This motor has been used mostly for trolling and has had oil changed on schedule. It suddenly started smoking and will foull a new plug within 1 hour of trolling. Compression test places both cylinders at 155 P.S.I.so I doubt a broken ring. I suspect oil is entering from valve side of combustion chamber, is it possible for oil to get trapped in the camshaft area or possibly seals that may have failed in this area?

Good compression(on a new engine) should be at 211-239 psi. You might have a leak down test done to see if there is **** by past rings.

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