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Results 1 to 9 of 9
  1. #1
    Join Date
    Mar 2007
    Location
    winder, georgia, united states
    Posts
    21

    Default 1979 mercury 115 tower of power ignition issues

    I'm pretty good with cars but am currently learning about outboards. The engine is spinning but I am not getting spark. I pulled the stator that only has two wires and when I test with a multimeter the ohms start out close the what they should be but then drains down to zero. Am I testing this wrong or is it bad? Another thing, there is no mercury switch and I don't see a kill switch. Will it start without a mercury switch or does it need to be grounded? If someone can post how to test the stator, coil, and trigger accurately I would greatly appreciate it.

  2. #2
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    2,581

    Default Re: 1979 mercury 115 tower of power ignition issues

    Sounds like you have older motor as has 2 wire stator. If you have a distributer with 6 plug wires check that you have 12v on red wire to switchbox on front of engine all the time and on white wire with key on and while cranking.
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  3. #3
    Join Date
    Mar 2007
    Location
    winder, georgia, united states
    Posts
    21

    Default Re: 1979 mercury 115 tower of power ignition issues

    Quote Originally Posted by faztbullet View Post
    Sounds like you have older motor as has 2 wire stator. If you have a distributer with 6 plug wires check that you have 12v on red wire to switchbox on front of engine all the time and on white wire with key on and while cranking.
    I currently have the ignition apart but will test this when I put it back together. I believe the stator is good. I guess my problem is the trigger. From what I understand the trigger tells the switch box to release stored power. I feel like I'm getting closer but if anyone has more knowledge they can share that would be great. Thanks for any help.

  4. #4
    Join Date
    Apr 2016
    Location
    barnegat NJ
    Posts
    2,707

    Default Re: 1979 mercury 115 tower of power ignition issues

    Try CDI electronics for trouble shooting procedures on the net

  5. #5
    Join Date
    Dec 2015
    Location
    maplevalley WA
    Posts
    3,469

    Default Re: 1979 mercury 115 tower of power ignition issues

    http://www.maxrules.com/oldmercs/Wiring/1966ona/35.pdf
    I believe this is your diagram. Do you have battery voltage at the white wire with the key on at the switchbox? Disconnect the mercury switch on the brown terminal on the switchbox and you should get spark. The stator is for charging the battery only your trigger is in the distributor.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  6. #6
    Join Date
    Dec 2015
    Location
    maplevalley WA
    Posts
    3,469

    Default Re: 1979 mercury 115 tower of power ignition issues

    http://www.cdielectronics.com/wp-con...S-134-3736.pdf
    http://www.cdielectronics.com/wp-con...S-114-2986.pdf
    It looks like you can bypass the trigger with a jumper wire and trigger the switchbox manually just put a spark gap tester on the coil wire touch the black terminal to ground quick touches and the coil should fire.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  7. #7
    Join Date
    Mar 2007
    Location
    winder, georgia, united states
    Posts
    21

    Default Re: 1979 mercury 115 tower of power ignition issues

    Well I was in the process of putting my engine back together to test the trigger out when I noticed that I was not supposed to take the pulley off the flywheel. Does anyone know how to realign the flywheel with the pulley? There is a notch for a key in the pulley. Is the notch for tdc or what is it marking?

  8. #8
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    2,581

    Default Re: 1979 mercury 115 tower of power ignition issues

    Pulley on flywheel don't matter in position as its just turning belt.. Making sure flywheel marks are aligned with TDC ..
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  9. #9
    Join Date
    Mar 2007
    Location
    winder, georgia, united states
    Posts
    21

    Default Re: 1979 mercury 115 tower of power ignition issues

    Just wanted to update as I have not been on here in a while. My ignition issue turned out to be the trigger. The trigger in the distributer tells the switch box when to release stored power. After replacing the trigger it starts up fine.

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