Unusual Power for a Sailboat

Discussion in 'Sailboats' started by Capt Ronrico, Jun 27, 2018.

  1. Capt Ronrico
    Joined: Oct 2015
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    Location: Pelican Bay

    Capt Ronrico Junior Member

    I have been thimking of powering a 30-ish-footer sailboat with an outboard of about 25 - 35 horsepower. And not the kind that mounts the engine on a trapeze-like mount, like some Folkboats or other small sloops, but a permanent, fixed location for an engine that can handles tasks greater than marina maneuvering. Engine would probably be locked in center position with steering accomplished by some more-or-less conventional rudder system.
    The first concern seems to be flooding by a following sea. But a lot of sporty fishers buzz around without being flooded by waves.
    Second is the engine mass being up high - but that should be manageable at the design stage. Crudely put - just throw a few more bars of lead into the keel - or buy your wife chocolate.
    I can envision two different approaches: one is sporty powerboat style with the engine just hanging off the back. The other would put the engine in an enclosure and probably move it forward somewhat.
    Constructive comments?
  2. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    The weight of a 30hp outboard is insignificant in that size of boat. If you have some kind of well in mind, being swamped would be more a function of how low to the waterline, the powerhead would be. But, you can get extended leg engines. The size of propeller (diameter) and gearing is another issue to be aware of.
  3. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Search these forums for "outboard well". There are a bunch of threads already, along with quite a few pictures/videos of some of the better examples of these. Short answer - even the bestest most perfect ones stink, but for the price differential, a few people still go this route. There are a lot of fussy details to get right. They operate on gasoline. The props aren't deep enough. They are fuel inefficient. They tend to seriously degrade reverse maneuverability when aft of the rudder. Exhaust fumes return though the well, so forced ventilation is needed. works ok on a mill pond on boats up to about 30'. 15 hp would be all you can use. 10 hp would be adequate. Not much recharge for house batteries - maybe 10 amps. Probably dragging the prop around when not in use unless you get really creative, which is a good reason to use the smallest possible unit.
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