inboard to outboard convert houseboat

Discussion in 'Propulsion' started by jtrott, Dec 20, 2012.

  1. jtrott
    Joined: Dec 2012
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    Location: scottsboro al

    jtrott New Member

    I am converting a 1971 50' house fiber hull from two 318 inboards to two 90 hp outboards. I am wanting to find out the best way to confirm the transom will handle them with adding plates over the old holes and using alum i beams and jack plates from bass boat to hang the engines
     
  2. rasorinc
    Joined: Nov 2007
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    Location: OREGON

    rasorinc Senior Member

    Can you give us the beam at the transon and tell us how it is supported on the inside of the hull? you will need the equavilent of 2 layers of 3/4" plywood and tie-ins connecting the sides to the new thicker transom and a minimum of 2 knee's 1 at each location where you intend to mount the engines. The knee's are made out of 3 layers of 3/4" plywood laminated together. Any chance for some pictures??
     
  3. jtrott
    Joined: Dec 2012
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    Location: scottsboro al

    jtrott New Member

    house boat inboard to outboard convert reply

    Thank you for the reply
    My boat is about 11.8' wide at the rear. The current transom is about 2.25" thick, in good shape. I have added a 3/8" piece of play wood on top of that on inside. The wholes that the drives left in transom were filled with 1.8" treated lumber, then body bondo, then fiberglass to get it flush with surface. Then the area's were covered inside and outside with 3/8" think by 18" SQ alum 4041 plates with lots of marine grade seal glue on backs. The I put two alum I beams side by side on the outside for brackets and a 1/4" steel galv 4" x 9" angle iron across inside of transom all the way and bolted all that thru the transom. No corner support added yet, but going to run metal rod supports from eye bolts putting on top of angle to each side of hull and two right up middle to boat deck frame.
    The hang jack plates on alum i beam and two 90HP Suzuki outboards
     

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  4. jtrott
    Joined: Dec 2012
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    Location: scottsboro al

    jtrott New Member

    more pic on houseboat inboard/outboard convert

    more pic
     

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  5. jtrott
    Joined: Dec 2012
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    Location: scottsboro al

    jtrott New Member

    more pic on houseboat inboard/outboard convert

    inside when in progress , now done
     

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  6. doitmyself
    Joined: Dec 2015
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    Location: Cabot, AR

    doitmyself New Member

    I am considering converting my houseboat to twin outboards

    I have a 1972 KingsCraft houseboat 15'x44', has 2-318 chrysler setup. i am thinking seriously about re-powering to outboards. If anyone has experience, opinions, or comments, I would appreciate any input. Boat weighs 14,000 lhs, is currently up on blocks at my residence. plan to do all work myself, as usual, interior/exterior rebuild due to partial sinking.
     
  7. Barry
    Joined: Mar 2002
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    Barry Senior Member

    There are two houseboat rental companies working out of Sicamous, BC Canada
    We had rented one many years ago with outboard power and they worked fine.
    Twin Anchor Houseboats and Three Buoys Marina
    I believe that Twin Anchor builds them from the hull up, not sure about Three Buoys but I suspect a phone call to both of them will get you the info on outboard models, gear ratios and props
     

  8. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Why change the 318's. They are good motors and part for them are cheap.
     
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