Having issues with a polar Kraft tunnel 1860

Discussion in 'Boats, Blinds, & Gadgets Forum' started by DeLaGwyn, May 6, 2018.

  1. DeLaGwyn

    DeLaGwyn New Member

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  2. DeLaGwyn

    DeLaGwyn New Member

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  3. DeLaGwyn

    DeLaGwyn New Member

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  4. calling4life

    calling4life Elite Refuge Member

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    Looks like you've got about 100% of the weight in the back, that's no good.
    You misunderstood what I meant by compression plate. I'm talking about a big plate that goes on your outboards anti-ventilation plate. Not a traditional whale tail, these compression plates, as the flats guys call them, are bigger and have more wrap around and bigger sides. They are essentially extensions of the tunnel that attach to your anti-vent plate on your outboard. They help hold all the water shooting out of your tunnel around the prop and lower unit. This helps prevent slip, it helps with boat control when jacked way up, helps with water pressure, helps with porpoising, helps with planing.
    You have to get the bow down, throw a few bags of cement up there, also, jack that motor up as high as it will go and still maintain plane when you do this.

    A tunnel hull for running shallow wants to run flat and on the surface, not in the water, not with a raised bow so only the back 1/4 of the boat is in the water, flat and on top of the water.

    I'd also be running floatation pods on that, but that's just me.
    Speaking of which, if it was me, I'd put a Trans Sport Boats, Boatright, or ShawWing compression plate on, I'd move a great bit of weight up front, or, to start with, throw some bags of cement up front to see what it needs, and I'd also jack the thing up as high as it will go and maintain plane, even if she was getting a little squirrely. If you can jack it all the way up and it still has grip, lift the motor up a couple holes on its mount.

    Looks like a nice boat, they can take a bit to figure out, but when you get these things running right, they are breathtaking in what they can do.

    Oh, and as an aside, when you get this thing running right, if you do want to be able to run that motor as high as possible, plan on having to install a low water pickup nosecone or a transom mount water pickup, personally, I'd go transom mount, but either way will help keep her cool.
     
  5. calling4life

    calling4life Elite Refuge Member

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    Oh, and another thing, when you truly run these with the motor high, it's a different driving experience, mine, is like driving your rear wheel drive truck down an icy road with the tires never maintaining traction. You're running with no/very little motor in the boat, so she'll feel like the arse end wants to slide around, and that's because it does, just be aware of this, if you're a competent person, it's not an issue, if you're foolhardy, there are plenty of experiences you can read about on Google of people dying, limbs taken off, etc... because their boat did a 180 or so on them at a moments notice.

    But that's when running the motor extremely high, don't let that dissuade you, running over inches of water is fantastic once you cure the fear.
     
  6. DeLaGwyn

    DeLaGwyn New Member

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    I have a 21ft blazer bass boat that hits high 80s low 90s speeds and I run it the same way over very shallow water at full speed. I was planning on putting a bobs tru Trac stabilizer plate and a transom mounted water pickup on it. Even if someone is up front I can’t trim the boat or plate cause it starts to hop really hard
     
  7. DeLaGwyn

    DeLaGwyn New Member

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    But however I do plan on putting batteries and fuel tank up front if it’s possible
     
  8. lax

    lax Elite Refuge Member

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    When you say "hop" are you referring to a bow high/bow low situation like the hull is dumping? If so I'd say the prop is causing it.
     
  9. DeLaGwyn

    DeLaGwyn New Member

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    No as is if you trim a boat too much it starts to hop in the front.
     
  10. lax

    lax Elite Refuge Member

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    That is what I meant, it is commonly called porpoising. Sounds like moving some weight forward as mentioned, or more neg trim is in order.
     

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