Mercury 25 HP Outboard- No spark

Discussion in 'Bubba's Outboards' started by atvracer, Apr 6, 2009.

  1. atvracer

    atvracer Member

    Messages:
    292
    State:
    IN-47501
    Went out to work on getting my boat ready for this year and cannot get it started, not an inkling of firing and looks to be no spark on either cylinder. Before I looked it over good enough I ordered a carb kit, plug wires and one coil because one of them looked like the wire wasn't making good contact. The motor is an '86 model with recoil start, not a complicated motor. I am guessing the powerpack or brainbox(whatever you call it) is bad. I also wonder if the on/off switch could be bad....can I splice the wires for now to see if that is the problem before I spend $100 on the box? I was so busy last year I never used the boat at all. Compression and reeds are fine. Thanks for any help!
     
  2. tbull

    tbull New Member

    Messages:
    3,318
    State:
    SW Ohio
    I haven't delt with the no spark problem to much, but you are right it can very well be (best case scenario), the kill swith. My buddies Vmax had no spark and that was the problem. I know sometimes you can't get those powerpacks to fail until they get hot. I would start with the kill switch just to start with the easiest first. But if you have not touched this motor in a year, it's kind of odd for the kill switch to start acting up on it's own. There are test you can do on the power pack, but you will probably have to purchase a manual and some special testing equipment. Sorry I can't help you out more, but unlike Bubba if I am not looking at something it's hard for me give very good advice when it comes to that ignition system...I have also had some pretty garbage spark testers that were telling me I had to no spark when I actually did. Manually put a fuel/oil mix in each cylinder behind the plugs and she fired right up..Wish I could be more help, but saw you getting 0 responses and figured I would through in my .02...

    Post your year, model, and serial number if you can. I will try to bring up the schematics somewhere so i can get a better look at the make up of your motor. I am sure Bubba will chime in.
     

  3. atvracer

    atvracer Member

    Messages:
    292
    State:
    IN-47501
    This motor is a 1986 25hp Mercury XD with recoil start and tiller controls. I bypassed the on/off switch and installed a new switchbox($110) last night and it still has no spark. From what I can tell via microfiche, the only other electrical components are the stator and trigger. I am going to take the flywheel off and see if either of those have loose connections. Does anyone have suggestions without breaking the bank? The stator is about $145 and trigger around $50. Looks like the flywheel has to be removed with an impact wrench.....The motor is getting gas, even sprayed into the cylinders, but like I said no spark.:sad2:
     
  4. atvracer

    atvracer Member

    Messages:
    292
    State:
    IN-47501
    Nevermind everyone I found the problem. The kill switch in the tiller handle went bad. After I disconnected it I have spark and it started on the first pull. I have ran it for about half an hour today. Now I need to repaint the boat....topic posted in modifications section.