Re: Merc question…..80s motor

[chinewalker]

I’ve got three of the 35hp twins in my shop right now, all purchased from local marinas, all falling into the 1985-1986 range. One was a running take-off. 135 psi in both holes, it’ll get basic tune-up stuff. Second had eaten one of the rod bearings at the crankshaft. Suspect it was due to moisture (poorly winterized? water in gas?) issue resulting in stuck bearings, then run, then melted bearing, then, well, enough knocking where they finally figured something was wrong and stopped running it. It’ll get rebuilt, as the bores are okay and I have another crank, bearings & rod for it. Third looks like it overheated and scored a piston, enough to stick a ring. Nothing broke, so it, too, will eventually live again. None have broken cranks, and the two that died had owner-neglect issues, not design issues. Over the years, I’ve had several of these big bore twins, from about 1979 & up. They seems to have ironed out most of the bugs by that point. I also have a much earlier 1969 35hp and 1966 35, and both are solid runners.