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Results 1 to 8 of 8
  1. #1

    Default 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    I have a 1976 650 thunderbolt 3cylinder, and I am having trouble getting all my cylinders to fire. I was out running the motor one day and all of a sudden i lost half my power. took it home my and my number 2 cylinder wasnt firing. All my coils are good i checked that. ( i have a second motor that i am using for parts). I took the switch box off of the other motor and switched them out.... still the same cylinder didnt fire. I pulled my flywheel off and checked the stator and the trigger assy. I switched the trigger system out and now i have #1 cylinder only firing, 2 and 3 wont fire.

    Questions is what would be the problem causing this could it be my stator or my trigger assy. I re-placed the wires on the trigger assy i switched. I just dont want to buy the wrong part and still have the same problem. Im trying to get this thing going before summer

  2. #2
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,279

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    I switched the trigger system out and now i have #1 cylinder only firing, 2 and 3 wont fire.
    Since the trigger made it worse start w/a known good trigger. Ohm the stator and check it carefully for minute cracks indicating possible heat related fractures.

    Use the CDI Troubleshooting Guide to confirm defective parts. http://www.cdielectronics.com/Support.aspx
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  3. #3
    Join Date
    May 2007
    Location
    Ireland,the only country in the world you can go North to go South
    Posts
    1,343

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    Sometimes a stator or trigger will give good readings cold,then when the motor warms up and everything expands it cuts out.Test when cold,run motor until operating temp,if not possible,then heat with a hairdryer and test again and see if there is a difference.There will be a small difference,what you are looking for is big differences.

  4. #4

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    Well what would most likely be causing the cylinders not to fire the trigger assy or the stator. i figured if the stator was bad i would be getting no spark at all on all of them.

  5. #5
    Join Date
    May 2007
    Location
    Ireland,the only country in the world you can go North to go South
    Posts
    1,343

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    The stator is the alternator and basically charges the battery.The trigger on the other hand sends the signal to the coil to fire.
    Last edited by haventaclue; 04-27-2012 at 07:05 PM.

  6. #6

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    so if im not getting sparks in coils its because of the trigger

  7. #7
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,596

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    You need to test the trigger.
    Last edited by racerone; 04-28-2012 at 02:45 PM.

  8. #8
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,334

    Default Re: 1976 Mercury 65hp 650 thunderbolt ingnition problems please help

    You can test the trigger coil with a meter; if there's continuity, it's wroking. It's just a simple coil.

    Jeff

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