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  1. #1
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    Bad engine noise?

    Anyone care to speculate on what might be wrong with this motor based on the sound? Here is a link to a 10 sec Video. For some reason the sound quality got messed up a bit but the Sound is more pronounced toward the end. It is a 2001 2 stroke 90ELPTO S/N OT268338.
    Last edited by MattG.; 06-07-2023 at 02:06 PM.

  2. Member
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    #2
    cant load on my pc
    .................................................. ...the scariest thing in life is the unknown ...................................

  3. Member
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    #3

    Thanks for letting me know.

    see if this works: Again, the sound seems to not transfer well, but is best heard right near the end of the video when the motor goes down to idle.

    Here is another: Link to google drive
    Last edited by MattG.; 06-08-2023 at 01:42 PM. Reason: added info

  4. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #4
    Compression and leakdown test would be a good starting point.

    It was not deep enough in the water when running it in the blue tub (good way to smoke the water pump).


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  5. Member
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    #5
    Thanks much Don. Compression is at 115 for all 3 cylinders. None of the plugs looked excessively nasty or different from the others. We used an inspection cam to look inside the cylinders via the spark plug holes to look at the cylinder walls and piston tops and they didn't show obvious damage.

    Regarding the second video, the one in the blue tub, we only ran it that way for about 1 minute (max), but then turned it off because we couldn't get the "piss stream" going. We tried that because we wanted to get some (water) back pressure on the prop. The only reason I posted that second video is that it demonstrated the "bad sound" much better.

  6. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #6
    I've seen a few of these that the upper crank bearing was excessively worn, the only thing I would say conclusively is that it's not likely to get BETTER on it's own. If you're going to fix it complete teardown, bearings, rings (better yet, pistons and rings with cylinders returned to factory specs), new seals and gaskets, etc.


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  7. Member
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    #7
    Thanks much. Complete teardown is beyond my level of expertise. Yesterday afternoon I took it to a reputable shop that specializes in Merc.

  8. Member
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    #8
    sounds bad agree with DON sounds crank related
    .................................................. ...the scariest thing in life is the unknown ...................................