Our OEM Yanmar is 3GM30 now 39 years old. 24 HP. 35 amp alternator. Kanzaki tranny with 2.61 reduction swinging martec 2 blade folding prop. Runs like a champ, smooth and quiet. Power is just right and enough for headwinds and seas There are several on ebay
If changing engine especially the brand be sure to account for changes to engine beds so it properly aligns as well as electric cables, throttle and shift cables, exhaust muffler and piping etc etc etc Best of luck John and Maryann Legacy III 1982 C&C 34 Noank, CT
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