Johnson suddenly runs rough

Discussion in 'Bubba's Outboards' started by jeffw51, Aug 6, 2007.

  1. jeffw51

    jeffw51 New Member

    Messages:
    288
    State:
    mo
    changed fuel line ,then removed old gas replaced with new.I added can of tuner in a can,next day took it for a test run.it startred right up and ran beautifully for twenty minutes i ran around the lake to run out the carb cleaners .i pulled into a cove to fish for about an hour thinking all my problems were solved.when i went to start it was a little hard to start,would not idle well,when i put it in gear it would die finally at about a quarter throttle it would chug along .every time i would try to increase speed it would die,so i limped it back to ramp?the boat ran better than ever what could cause such a problem fouled plugs?115 johnson
     
  2. Plowboy411

    Plowboy411 New Member

    Messages:
    918
    State:
    Georgia
    I would start by draining bowl on the carb/s and cleaning the spark plugs. if that don't do it??? well ??? the Plowboy yacht goes to the yacht / boat doc.lol good luck friend.
     

  3. AwShucks

    AwShucks New Member

    Messages:
    4,532
    State:
    Guthrie, Oklaho
    Hopefully, you have a manual for your specific outboard. If not, get one as they are indispensable.

    First thing on any outboard maintenance/repairs is to run a compression check. This tells you a lot about the condition of the motor and possibly provides leads as to where you could look first.

    I would next look at the carbs. Sounds like they may have some trash which blocks the fuel to the cylinder. It would probably run you about $70.00 to get kits for 3 carbs. Don't rush the job. Disassemble one carb, put it in carb cleaner to soak all night, clean all parts and use compressed air to blow out all the different ports and tubes. Take your time assembling the carbs and check/recheck all the distance measurements for your carb. When you have your first carb rebuilt, disassemble the second. Then after you completed that process, do the third. Do one carb at a times as parts may be interchangeable, and they may not be interchangeable. This way you know what came off the carb went back on the carb, or its replacement part did.

    Once your carbs are all set, get the book about and do the link and sync procedures. After that, your ready to water test the motor again.
     
  4. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Couldn't have said it better lawrence
     
  5. jeffw51

    jeffw51 New Member

    Messages:
    288
    State:
    mo
    thanks guys i am going to test spark and compression then check carbs.
     
  6. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill