converting from I/O to outboard- cost vs efficiency

Discussion in 'Sterndrives' started by daddy, May 15, 2006.

  1. daddy
    Joined: May 2006
    Posts: 3
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    Location: coastal nc

    daddy New Member

    hello. I recently purchased a 1975 21' fiberform cuddycabin with trailer. The boat is in fantastic condition. The motor must be replaced. My question is should I put in a new in/out board motor or seal the transom and mount an outboard on a jackplate? Which is more economically feasible? I am concerned about sealing the hole from the outdrive. Also would like to know the maximum hp for a boat this size. All input will be greatly appreciated.
     
    daddy, May 15, 2006
    #1
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    An outboard will take the weight far aft. It may cause porpoising and other running problems.
     
    gonzo, May 18, 2006
    #2
  3. daddy
    Joined: May 2006
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    Location: coastal nc

    daddy New Member

    yes i understand but have seen many setups like that, an outboard on a boat that used to be i/o. what are the specs im looking for?????
     
    daddy, May 18, 2006
    #3
  4. Raggi_Thor
    Joined: Jan 2004
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    Location: Trondheim, NORWAY

    Raggi_Thor Nav.arch/Designer/Builder

    Why do you want to do this?
    In NOrway, the smaller Mercruisers cost less than an outboard.
    How many HP do you need?
     
    Raggi_Thor, May 19, 2006
    #4
  5. daddy
    Joined: May 2006
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    Location: coastal nc

    daddy New Member

    150 hp at least...its a heavy boat and i want an easier engine to access and work on
     
    daddy, May 19, 2006
    #5

  7. Raggi_Thor
    Joined: Jan 2004
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    Location: Trondheim, NORWAY

    Raggi_Thor Nav.arch/Designer/Builder

    OK, I see.
    You can compare weights at www.marinepower.com for example.
    I suppose an outboard is lighter than an inboard, so moving the weight a little longer aft is probably not a problem.
     
    Raggi_Thor, May 19, 2006
    #6
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