2005 Mercury 15 hp 4 stroke

Discussion in 'Outboard Maintenance' started by cpauly33, Apr 8, 2011.

  1. I picked up a 2005 Merc 15 a couple weeks ago. When the seller test ran the motor for me it started right up and ran good once it had a minute to warm up. I took the motor home and discovered the gas in the tank was bad. So I got fresh gas and again the motor ran like it should.

    The next day I took the boat out and right away I had trouble getting the motor started. Once started it won't idle and at full throttle the motor isn't running at full song. Sounds like its missing something, don't know too much about motors to really tell you whats happening. I ran the motor off and on for about 4hrs and it didn't get any better.

    I hope its not something serious. Any thoughts?
  2. DuckNut

    DuckNut Brandon, FL

    Most likely the carbs just need a good cleaning. Might have some small pieces of varnish stuck in the jets. If it is carburated. Does not sound like a serious issue.

  3. Ok, so with the help of a friend I've cleaned the carb, changed the fuel filter and replaced the fuel tank line. All of which were clogged up. I also cleaned the tank and the fuel line connections.

    Motor won't started. Pull on the cord, turns over but nothing happens.
  4. Brett

    Brett > PRO STAFF <

    Is the kill switch back in run position?
    Do you have spark at both plugs?
  5. Kill switch is good.
    Both plugs gave me a good shock. Scuffed them up with some sand paper and checked the gap.
  6. Brett

    Brett > PRO STAFF <

    Sounds like you still aren't getting fuel through the carb.
    Did you check the fuel pump for debris also?
  7. I haven't opened up the fuel pump but I did remove the line from the carb and fuel came out.
  8. Brett

    Brett > PRO STAFF <

    If you have spark and compression, then the only thing missing is fuel.
    Make sure you have a full function fuel system, all the way to the carb.
    If fuel is reaching the carb and filling the float bowl, then the carb is still not functioning properly.