Got fire

Discussion in 'Bubba's Outboards' started by duckcommander, Apr 9, 2008.

  1. duckcommander

    duckcommander New Member

    Messages:
    3
    State:
    South Carolina
    I have a 1993 Mercury 115.

    I have fire on the bottom two cylinders. Correct me if I am wrong, but this is normal for this motor.

    However, it will not stay running after cranking... not even for one second. Seems to me that it is a fuel pump problem. So first thing I did was pull the line from the pump running to the carburetors to see if there was fuel moving. There was. I did not check the actual pressure coming out of the pump, but I imagine it is sufficient.

    I originally had ignition problems with no fuel problems to speak of. I replaced the stator as well as the switchbox so now I have spark. This Merc is a nightmare. Not to mention the Motorguide Wireless went down too. I could bang my head against the wall. [​IMG][​IMG][​IMG]

    ANY IDEAS?

    What I have done:
    - Replaced the plugs and properly gapped them
    - Flushed and replaced with fresh fuel
    - Priming bulb pumps until it is tight
    - Checked the out line on the pump and fuel is pumping while cranking (it does).

    Thanks guys (and gals).
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    I8 am going to have to think about this one a few. I have that motor in the 100 h/p I am assuming it is the one that is a four cylinder and it idles on 2 and kicks the other 2 in at 3 grand I think.
    What you can try is take a squirt bottle with some pre mix in it and crank it over and squirt fuel into it to see if it keeps running while doing this and that will tell you if it fuel or something else. I am assuming at replacing the stator you did leave the spark advance where it would move . when you advance the throttle.
     

  3. catfisherman_eky3

    catfisherman_eky3 New Member

    Messages:
    2,296
    State:
    Kentucky
    welcome to the boc from kentucky there are plenty of people on here that can help you
     
  4. duckcommander

    duckcommander New Member

    Messages:
    3
    State:
    South Carolina
    Now that I think about it. Shouldn't it be the top two cylinders firing on the 2+2 system? That would mean some wires are backwards or the new switch box is wacky. Hopefully the former.

    So the question is, can I swap the wires around? I did wire them as per the color labels on the switchbox. Would switching them around to get the spark to the proper cylinders damage anything? Then I would have to figure out which is firing, seeing as how I would need to ensure the proper firing order. AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH POOOOOOOOOOOOOOOOO.:eek:oooh:
     
  5. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    You'd better figure it out, because the lower carbs aren't set up for idling.