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Results 1 to 6 of 6
  1. #1

    Default 50hp Outboard loss of power

    I have a 50hp Mercury on my pontoon boat. While running at WOT (approximately 5000 rpm) the motor suddenly dropped to around 3000 rpm. It happened a few times this weekend, but cleared up and continued to run fine. But this time it would not recover. The motor will start and idle fine. Full power in reverse and revs up fine in neutral. Changed the fuel filter and checked the spark just by removing plug wire and listening for the slight change in engine speed. All that seems fine. Any ideas on what else it could be?

  2. #2
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 50hp Outboard loss of power

    What year and SN?
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  3. #3

    Default Re: 50hp Outboard loss of power

    2006 50 ELPTO. S/N 1B368445. I forgot to mention that I also replaced the fuel primer bulb. Also, when the engine was acting up, if I pushed the choke, it would go full throttle for 1 second then back to 3000rpm. Kind of strange that I can get full rpm in reverse and in neutral but not in forward gear don't you think?

  4. #4
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 50hp Outboard loss of power

    Always check for loud blue snapping spark at each plug. It sounds like there is some crud bouncing around in one or more of the carbs. Full rpm in (don't do it)neutral/reverse means nothing since there is no load in neutral and little in reverse due to prop design. Examine the spark plugs' burn pattern...brown color is good. Change the fuel filters and clean the carbs.
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  5. #5

    Default Re: 50hp Outboard loss of power

    Thank you for your help. I will check the plugs and carbs as soon as I get the chance.

  6. #6
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,682

    Default Re: 50hp Outboard loss of power

    Using the primer to increase RPM points directly at fuel propblems.----------------Clean / inspect the carburetors.----Never wind up one of those motors in nuetral as it proves nothing !

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