Yanmar YSM12

[SunnyJ]

Greetings

Interested in a clean 27 foot Sailboat(Late 70's)with original YSM 12 single.
Vibration, lack of power and scarcity of parts common thread. The odd sailor hails the engine as a wee masterpiece. Will 2nd hand/rebuilt parts be around for a while? We hear about other relic engines from the stone age still kicking. Are these engines old school heavy, low rpm diesels? I like one lung and I like simple. The internet can exaggerate thangs. Any feedback?

Bob