Planing Hull / Sterndrive Tidal (Drying) Harbour

Discussion in 'Boat Design' started by Texel Tom, Sep 6, 2016.

  1. Texel Tom
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    Texel Tom Junior Member

    Hi, Stupidly I have just purchased a Scandinavian (Finnish) 26' fast cruiser with a Volvo DP sterndrive and hope to keep it on my mooring which dries out each tide to fairly hard sand. The added issue is that the sterndrive does not trim up high enough to clear the keel line and sits approx. 2" lower.

    I am hoping for some ideas on how I can overcome this dilemma which will both raise the keel clear of the beach to protect the leg but which will also keep the boat upright at low water. I have been considering both adaptions to the hull or some form of cradle however please bear in mind that the harbour often has a small swell in certain wind directions and the fore and aft moorings allow considerable lateral movement.

    I would really appreciate any thoughts and ideas.

    Many thanks

    Tom.
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    What if you put the helm right over ?
     
  3. Texel Tom
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    Texel Tom Junior Member

    Ha! I feel a bit stupid because I didn't think of that. I will go and check tonight. The hull is deep v through to the transom so there is a chance that it would clear. Thanks for the tip!
     
  4. gonzo
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    gonzo Senior Member

    Sailboats use legs, but they may look goofy on a powerboat.
     
  5. Texel Tom
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    Texel Tom Junior Member

    Thanks gonzo I have seen those and they are quite common here but only stop the boat tipping over with the main load still supported by the keel. Unless the sterndrive is clear I will need to lift the hull off the beach somehow.

    Thanks Tom.
     
  6. gonzo
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    gonzo Senior Member

    When you trim the sterndrives all the way up, do they not clear the keel?
     
  7. Texel Tom
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    Texel Tom Junior Member

    Not when the helm is straight but I am just going to check what happens when the helm is hard over as suggested by Mr Efficiency above.. When its straight its about 2" lower and that's not allowing some settling of the keel into the sand.
     
  8. Texel Tom
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    Texel Tom Junior Member

    Just been to the boat and unfortunately even at full lock the sterndrive still sits approximately 2" below the keel line so I'm back to the original question.

    Any thoughts on adaptions either fixed or removable which will both lift the keel up to clear the outdrive and also keep the boat level when on the beach?

    Thanks!
     
  9. mydauphin
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    mydauphin Senior Member

    Tie a couple of used tires under in stern, put some rocks in then to make sure they sink.
     
  10. gonzo
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    gonzo Senior Member

    You may have to install legs on the stern.
     
  11. Mr Efficiency
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    Mr Efficiency Senior Member

    Defeats me why the tilt range does not have the drive clearing the depth of the bottom, easily. I can't visuailize how this is occurring.
     
  12. Texel Tom
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    Texel Tom Junior Member

  13. Texel Tom
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    Texel Tom Junior Member

  14. Texel Tom
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    Texel Tom Junior Member

    Wow! That's big sorry! First time I have tried to do that... Hopefully you can get an idea from this pic!!
     

  15. Barry
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    Barry Senior Member

    Our second last boat had diesel DP's and there was a setting that controlled the height that the leg would tilt up. I was told this was so the leg would not hit the bottom of a swim platform.

    When we had an issue with the tilt on the legs, the mechanic had to reset the upper limit.

    Not sure if this would be the situation in your case but probably worth contacting Volvo or a knowledgeable Volvo dealer to confirm

    Mind you the upper part of the leg appears to be pretty close to the gimbal housing
     
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