New propulsion system for my boat

Hello all.

Im in need of some expert advice. I have a 38 foot catermeran, with twin volvo D-6's and outdrives. The outdrives are constantly failing and as a result I am looking into alternative methods of propulsion. particularly surface peircing drives. The boat needs to be able to transit at about 25 knts, but will spend 80% of its hourrs running at speeds between 4 and 10 knts. I am looking closely at seafury drives. Does anyone have any ideas on how well these drives might preform in my situation. particularly, can they be protected by collision? The images I have seen the drives are exposed with the props being the lowest part. Do they preform well at low speeds? do they create an above average amount of acoustic noise? ANy input would be greatly apreciated

Thnx

 

You will be far happier with the Arneson Surface Drive.

http://www.arneson-industries.com/

 

Seafury are popular for sea going vessels they are fixed and you can antifoul them. The proplleor is what does the buisness what holds it there is not as important as where it is held.

I have seafury propelors on a semidisplacement catamaran, under 15 knots I have nothing but rpm ,It has to come on the plane. 10Kts for me would be 2500rpm and a lot of thrashing white water, some think I am jet driven.

But up at 17 I would be 3400 , the props dry out and start to bite, I go faster yet pulling back on throttles, I settle in at about 28% prop slip.

Noise? nothing your have to feel the smoothness to believe it. If you want to troll surface drives are not suitable

 

I do lots of trolling for Salmon and Tuna. Arnesons work perfect. Just trim them down. Also Arnesons steer pretty good in reverse. Fixed drives: not.