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  1. #1

    Default Spark plug recomendation

    40hp 4 stroke efi 3cyl. recomended plug Champion RA8HC

    I Troll a lot at around 2mph, should I switch to a different plug? What would be recomended?

  2. #2
    Join Date
    Jun 2013
    Location
    Duluth Mn
    Posts
    4,415

    Default Re: Spark plug recomendation

    I would leave the recommended spark plug. Be sure to use non-oxygenated fuel. Why? Ethanol produces nearly 5 percent less power....and it's shelf life is about 1/10th that of pure petrol.....it's very hydroscopic, (absorbs water).

  3. #3
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    6,305

    Default Re: Spark plug recomendation

    Quote Originally Posted by timguy View Post
    I would leave the recommended spark plug. Be sure to use non-oxygenated fuel. Why? Ethanol produces nearly 5 percent less power....and it's shelf life is about 1/10th that of pure petrol.....it's very hydroscopic, (absorbs water).

    Hygroscopic
    Chris
    Dockside Marine Services
    Jersey Shore.
    Mercruiser/Mercury Certified
    Let the insanity begin.

  4. #4

    Default Re: Spark plug recomendation

    Thanks, I would love to use non ethanol fuel but I can't find any in my area. Do you recomend something I could add to the fuel to help?

  5. #5
    Join Date
    Jun 2013
    Location
    Duluth Mn
    Posts
    4,415

    Default Re: Spark plug recomendation

    Thanks, Chris.
    Nothing eliminates the ethanol. Where are you living?
    Last edited by timguy; 08-05-2021 at 09:45 AM. Reason: Typo

  6. #6

    Default Re: Spark plug recomendation

    Orange County NY, I have looked using an app but closet is quite a ride.

  7. #7
    Join Date
    Jun 2013
    Location
    Duluth Mn
    Posts
    4,415

    Default Re: Spark plug recomendation

    That's crazy. A full 50 percent of my work is ethanol damage related.

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