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Thread: 20hp4stroke bog

  1. #1

    Default 20hp4stroke bog

    Hello Iím new to this so here goes, I have a 08 20hp 4stroke as a kicker on my 23 Ď pontoon, it runs great with earmuffs but in the water pushing the boat it has a nasty big the hole time and fowls plugs any help would be appreciated thx

  2. #2
    Join Date
    Mar 2019
    Location
    Ottawa Canada
    Posts
    555

    Default Re: 20hp4stroke bog

    check to see if its sparking on both cylinders first.

  3. #3

    Default Re: 20hp4stroke bog

    It may well be carbon build up on the rings,,,causing poor compression One can of Mercury Powertune sprayed into the Carb might take care of it.... it is a fairly inexpensive something to try (around $12) before taking it in for service....follow label directions

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