engine/propeller match

[dave kibble]

I want to convert a 18' to 20' runabout to a pocket cruiser. I intend to run the hull as a semi displacement craft. I would like to convert the hull to an inboard and us a 10 hp 3600rpm diesel does anyone know what prop to use or good source to spec the prop. thanks

[marshmat]

Are you thinking of something like a lake bowrider or deckboat? Or are you looking at an aluminum fishing hull? 10hp on a typical 19' bowrider will only just get you hull speed, and these hulls really can't do semidisplacement mode. On a lighter, shallower-V aluminum hull you might be able to do it. You'll need a weight range and more info before going prop-hunting.

[cyclops]

Call Michigan Wheel. They have sized every combo.

[Chickadee]

Same question (for my last virtual design). The form at Michigan Wheel is great but I'm not sure what pitch and diameter is best.

The boat is a 3,5-4 tons, 9 meters LOA/LWL sailboat, a 18 hp inboard diesel would be great, though I find them very large for such a light and small boat.

I'd like to know what diameter to use for the propeller. 1'4'' ? What would be the pitch then, 1' (tri-blades)?

Any link, formula is welcome.

First Yanmar model is 3600rpm/3.22:1 gear, another, Volvo, is 3200rpm/3:1, both 18 hp. Are different props needed ?



Thanks

[cyclops]

Call Michigan Wheel on a telephone. It is better than E Mail.