Is this a bad idea?

Discussion in 'Jet Drives' started by drev500, Sep 14, 2015.

  1. drev500
    Joined: Jul 2015
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    drev500 Junior Member

    I am trying to retro a jet ski pump into a hull but the drive unit from nozzle to front of motor is about 4' 10". I am trying to utilize as mush space inside the boat without the engines take up too much space so I thought about pushing the driveline as far aft of the transom as possible.

    How important is it for the pump intake to be under the hull? Can some of the intake be after of the transom (providing a smooth transition so as to not introduce turbulence)?

    I came across a guy who did what I am thinking of doing. Here's a picture: [​IMG]

    Here's the build thread he started that I got the picture from:
  2. hoytedow
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    hoytedow Carbon Based Life Form

    With the engine forward you will have better trim/less squat. Maybe factor that into the plan.
  3. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Well, ask the guy who "did what I am thinking of ". Or has he not tested it yet ? If not, maybe wait and see. But, of course, what might work in one hull, may not in another, different one.

  4. mikkijayne
    Joined: Jul 2015
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    mikkijayne Junior Member

    The PP65 jet works a lot like this - the drive is entirely on the outside, bolted to the transom, and the inlet is underneath the flywheel. The drive coupling is only about 6" from the transom.

    (this is a West End, but they're virtually identical)


    These are mostly fitted to sidewinder-type hulls in the UK, and give plenty of space for people since the engine can be quite far back. If you could create an inlet shape in the hull then I don't see why you couldn't contrive something like this with the other types of jet?
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