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Mariner 9.9 correct spark plugs

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  • Mariner 9.9 correct spark plugs

    Hey guys I bought a 1988 22ft. Sylvan last year. It has a 3 litre omc and it came with a Mariner 9.9 4 stroke outboard. I can't find a tag on the outside of the motor any where. I did find a number on what looks like a sof-plug under the hood though. I believe it may be the serial number. OH 001802. Does anyone no how to decipher these numbers. I think it is a 96 thru 98 model going by the paint. Need to know the correct plugs as it is the hardest starting outboard I have ever come across. I just un-winterized the main engine today and it purrs like a kitten. I want to get out on the Columbia river for some sturgeon fishing asap. Any help will surely help!!

    Here are a couple shots although more of the boat than the troller

    Pics were taken the day I purchased the boat. we drove from Western Washington to Northern Idaho to get it. We just love it!

  • #2
    Re: Mariner 9.9 correct spark plugs


    That s/n comes up as:

    9.9 1995 EL 4-Stroke H000233 - H002999

    It is a model:

    7F10273DD MARINER 1995 9.9

    Parts listing:



    Service Manual: P/N 90-827857R1



    • #3
      Re: Mariner 9.9 correct spark plugs

      Hey thanks so much for the quick response. I really appreciate it.



      • #4
        Re: Mariner 9.9 correct spark plugs

        Hey Zilla, welcome to the hardest starting 4 stroke outboard world...lol I have that exact same engine and have been through hell and back with that motor. Finally got it running again since after taking it to a local outboard repair shop. Took it on the lake after repair..ran it about 5 mins. and it never started again til' yesterday. Read an article about the carbs on "our" motors and said that the carbs have very small orifices and plug up very easily. Bought a new carb for it, cleaned out my 6 gal. gas tank throughly and let it completely dry out and found a station in my area that sells non-ethanol gas for now. I still use an additive like seafoam' to help with any moisture. Engine seems to running fine now in the driveway but will be taking to the lake this week for the real test. (making sure my battery is charged for trolling motor..just in case). I know alot about this engine so if u have anymore questions contact me at yankeebassman@yahoo.com Also here are the stock #'s for most auto parts stores for spark plugs...not the number thats on the plug itself but for the stores use. NGK plugs-7023, Champion 808, Autolite 4194. Hope this helps some. Keep in touch, Doug.