Info on Martec folding props?

[sailstoo]

I'm considering putting a Martec folding prop on my Yanmar diesel powered C&C 34. My question is how much power will I lose in reverse and what are other downside considerations? The reason I'm considering a Martec rather than a feathering prop is price. Martecs are available used for about $250+ and Martec will rebuild them/tune them inexpensively. Also, anyone know the prop shaft diameter for this boat? Thanks.

[Hudsonian]

I have a 13x13 martec prop on a 30' fin keeeled sloop with a Yanmar 2GM. The prop works well in reverse at 1800 RPM or more. As I recall, Martec claims that the prop can stop a boat going hull speed in four boat lengths. I believe it. OTOH, it's useless in reverse at low rpm.

Regular maintenance is required - a rebuild every three years or so.

[JimsCAL]

I have lived with a Martec on my Cal 9.2 for 20 years. Very pleased with it. Thrust in reverse is much better than you would expect as Hudsonian noted.

If you contact Martec they will give you a recommendation on the prop size. Just measure the shaft diameter.