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Clunk noise from running gear

Discussion in 'Props, Shafts & Seals' started by C4ENG, Feb 16, 2011.

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  1. C4ENG

    C4ENG Senior Member

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    Has any one ever experienced a clunk noise after taking a vessel out of gear while maneuvering?
    If so, did you figure out why?
    Or if you know why you would hear a clunk noise after going out of gear on a 150+ size vessel, I would really appreciate if you would share your knowledge.
  2. Capt J

    Capt J Senior Member

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    I've seen it where there was a line wrapped around the propellor shaft. The line would stay tight when the shaft was turning, then when turning the oposite way the end wacked the bottom of the hull.

    I've also seen it when a motor mount was bad.Are you getting any engine movement? I've also seen it where Twin Disc used too long of bolts on the flywheel and they were hitting, before a recall was sent out.
  3. C4ENG

    C4ENG Senior Member

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    Or loose. Great place to start inspecting.
  4. Capt J

    Capt J Senior Member

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    Possibly, check the shaft coupler bolts as well.
  5. Beau

    Beau Senior Member

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    Indeed, you need to check the whole drive train on each engine. A loose prop knot can let that prop slip, a loose shaft zinc can bounce, the shaft nuts coud be loose, etc.... start with the simple (underwater and work your way back to the engine. Just my suggestion.
  6. corinthian99

    corinthian99 New Member

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    It'd help with a few more details;
    - Is this a new development?
    - Is this present on both engines?
    - Is the captain new and banging it over fwd to reverse with gay abandon (usual cause)?

    Good luck.