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Muffler failure

Discussion in 'Post Yacht' started by RT46, Aug 26, 2014.

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  1. RT46, Aug 26, 2014
    #1
    RT46

    RT46 Senior Member

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    Location:
    Long Island, NY
    I just saw a posting on another Forum about the sinking of a 46 Post with 671 TIBs due to muffler failure.

    Seems like there a good lesson learned in the posting to have something available to plug the exhaust outlet in the event of a loud backfire followed by flooding, or flooding due to muffler failure.

    Im not sure if I am allowed to post the site and link, so here is some of the reported info:

    "The boat is 485 hp powdered 6-71TI's. Upon start up on Sunday there was a loud bang from the Port engine. All was shut down and 3 mins later she was headed fast to the bottom. Today we found the port side fiberglass muffler had one side completely blown out. The cause of flooding was obvious. The question is what what would cause a failure of this kind? Catastrophic failure of a muffler due to pressurization is the assumption. The first guess is vermin or birds nesting in the exhaust. But that said one would assume the engine would simply die due to exhaust restriction. "
  2. chesapeake46, Aug 26, 2014
    #2
    chesapeake46

    chesapeake46 Senior Member

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    How does some one hear a loud BANG and not go investigate ?
  3. mwwhit1, Aug 26, 2014
    #3
    mwwhit1

    mwwhit1 Senior Member

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    Jersey City NJ\Boca Raton FL
    I guess your 46's sit lower in the water. Full fuel and water and my 43' exhaust is just touching the water line. Always made me feel safer knowing the exhausts are above the waterline almost always.

    I see the newer sportfishers and the exhausts are almost totally under. A bit concerning.

    From what I saw, the muffler has a single baffle in it with an opening along the bottom. So plugging that with a nest of some sort seems very likely.
  4. chesapeake46, Aug 26, 2014
    #4
    chesapeake46

    chesapeake46 Senior Member

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    You are correct.
    My exhausts are always 1/2 submerged.
    It must have been a heck of a nest to be stronger than the muffler material.