20hp Honda outboard mounting

Discussion in 'Powerboats' started by Graham Tapper, May 20, 2020.

  1. Graham Tapper
    Joined: Mar 2019
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    Graham Tapper Junior Member

    Help needed - Due to pandemic my outboard is still at the shop; Meanwhile I am building a small runabout woody and need to know the minimum dimensions required for the transom well. Remote steering will be used. If you have one of these motors please message me with the clearances needed.
     
  2. ondarvr
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    ondarvr Senior Member

    What year?
     
  3. bajansailor
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    bajansailor Marine Surveyor

    I guess that the main dimension of concern is the fore and aft length of the well, to ensure that you have enough room for the motor when it is tilted up?
    Will you have cable steering, or hydraulic?

    We always like to see boat building projects on here - can you post a photo or two showing your progress to date please?
     
  4. hoytedow
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    hoytedow Wood Butcher

    20190514_112733~2.jpg
    You will need enough room for through transom motor bracket bolts and wrenches. I will measure in the morning and post here.
     
    Last edited: May 20, 2020
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  5. hoytedow
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    hoytedow Wood Butcher

    20200403_105916~2.jpg The motor shown is 20hp bought new in 2017.
     
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  6. Mr Efficiency
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    Mr Efficiency Senior Member

    Engine makers typically have drawings of clearances required. Just look up the model on their website.
     
  7. bajansailor
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    bajansailor Marine Surveyor

    That is a very fine wee skiff Hoyte - at a risk of some thread drift, can you tell us a bit more about her please?
     
  8. DCockey
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    DCockey Senior Member

    I have looked for such drawings on several manufacturers' websites in the past without success. The only outboard installation drawings I have found online were for Mercury outboards and they were on a website of Brunswick Corp, owner of Mercury, and drawings of some Yamaha outboards in an old Yamaha rigging guide on a third party website.
     
  9. hoytedow
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    hoytedow Wood Butcher

    20200521_151802~2.jpg 20200521_151705~2.jpg 20200521_151438.jpg
    Thanks. Measurements as promised.
     
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  10. hoytedow
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    hoytedow Wood Butcher

    20200521_154656_HDR.jpg Tape measure is English not metric so 2.54 cm = 1 inch.
     
    Last edited: May 21, 2020
  11. hoytedow
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    hoytedow Wood Butcher

    Based on that I would say a 30 cm x 30 cm area of clearance should serve nicely.
     
    Last edited: May 21, 2020
  12. hoytedow
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    hoytedow Wood Butcher

    Of course you can go larger.
     
  13. bajansailor
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    bajansailor Marine Surveyor

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  14. Graham Tapper
    Joined: Mar 2019
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    Graham Tapper Junior Member

    Hi Hoytedow and Hi to Bajansailor,
    Very many thanks to both for these posts. It helps enormously to know those sizes I have to play with at the transom. I think from the images that I have just, and only just, allowed sufficient room for the Honda which is the 20hp new models with remotes. I should be able to get back into the suppliers shop in early June to measure up exactly, so I won't start to deck in the area about the transom until the double check is done and I have got the wood that's also locked up till then.
    Best Regards,
    Graham.
     
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  15. hoytedow
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    hoytedow Wood Butcher

    Our pleasure.
     
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