Outboard Motor Well

Discussion in 'Multihulls' started by kelldog, Jun 7, 2009.

  1. kelldog
    Joined: Jun 2009
    Posts: 42
    Likes: 1, Points: 8, Legacy Rep: 15
    Location: Bakersfield, CA

    kelldog Junior Member

    Outboard Motor Well


    Greetings to all;
    New member here....
    I am considering cutting out a well in my Cross trimaran for my outboard motor. There is a spot where the framework has been built in to do this but was not finished. I have a 5hp 4 stroke that I use ( I need/want a 9.9hp) and with the outboard bracket I use I still have an issue with cavitation in choppy water. Drives me nuts!!!

    I would have to rig something that would allow me to raise the motor up when not in use. I don't think I have enough clearance to be able to get the prop completely out of the water but that might be ok.

    Any ideas or thoughts on this? My Cross is 28/30 ft. The well is in front of the rudder and alittle to the starboard side...not centered.

    Thanks your input

    S/V Mystic
    Long Beach, Ca
  2. peterAustralia
    Joined: Mar 2006
    Posts: 385
    Likes: 34, Points: 28, Legacy Rep: 233
    Location: Melbourne Australia

    peterAustralia Senior Member

    I have a well in my small multi.

    I found that I had problems is a chop in that the motor would make funny sounds when a wave passed. I worked out that the exhaust was too deep in that water and creating back pressure. So it was not the well itself but insufficient height of the well.

    You need a plate of some sort that goes back when the motor is removed to retain a smooth flow. To get the motor out easily, I suppose some sort of rotating mechanism. so that the motor fits onto a block (4 x 2 timber) that sits on the lip of your well, but is not physically attached to the well. This way the whole thing could be lifted out.

    The trouble with this is that you would need space forward for rotating arms for the mechanism.

    A vertical sliding mechanism might work too, but it would need to be braced securely to the well before the motor is used.

    You do not have enough length in your well to have the motor just kickup normally...
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