40hp outboard mercury

Discussion in 'Outboards' started by lonestar, Jul 10, 2006.

  1. lonestar
    Joined: Jul 2006
    Posts: 1
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: michigan

    lonestar New Member

    hi everybody, i have a 1976 40hp mercury 2 cyl. outboard and when i am
    cruising at 3/4 throttle it runs great but when i go to full throttle it starts
    to jugg, stubble, and then die, but it starts rit back up and i can go
    but it does the same thing again. any help or suggestion needed.
    thanks
    lonstar
     
  2. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    I can think of two things that might be involved: fuel, or ignition. It's possible that your carb is getting a bit clogged and can't flow enough fuel at wide-open, causing it to go lean and start sputtering. It could also be a problem in the ignition system- check the spark timing, the plugs, coils, etc.
    Anyone have any better ideas?
     
  3. SmithCraft64
    Joined: Aug 2006
    Posts: 57
    Likes: 2, Points: 0, Legacy Rep: 15
    Location: California

    SmithCraft64 Junior Member

    Whens the last time you changed or blew out your fuel filter? Check your carb adjustments. It may be starving on the high end. Hope these suggestions help you.
     

  4. PeO
    Joined: Aug 2006
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Karlsborg Sweden

    PeO Junior Member

    Curious about the results... I think I have the same problems at my Merc 650 -1970....
    I have owned it for a mounth and there was no diafragm in the fuel-pump when I bought it..
    Now I have put in the parts and tryed agian... It runs smooter but with full throttle it runs up to a minute then it slows down... :mad:
     
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