99 merc four stroke 40hp, no spark in number two cylinder

[SibetOR]

Hello. I am helping my friend troubleshoot his mercury motor. We checked the spark the old way with the plugs out and pulling the rope with a spark plug grounded to the block. Number two wasn't firing at all but the other two were. I unpluged the wire going to the coil and tested it with wire from another cylinder it then sparked (number two coil is good).

Not sure what to check next. Should we replace the ecm (ecu) or check the stator next.

Thanks for any help you could offer.

 

[guyjg]

Test the trigger and stator.

 

[SibetOR]

Thanks for the quick reply. Any tips on testing them?

 

[guyjg]

look here http://www.cdielectronics.com/Support.aspx

 

[SibetOR]

Thanks for that info. i will be checking in a day or two. I will let you know how it came out. Thanks again.

 

[faztbullet]

It will be one of 3 things: 1) coil boot as these are known for wire to burn up in end of boot... 2) coil.. just swap to different cylinder to test...3) stator as this motor has no trigger, just swap lead from a firing cyl to the non firing ,if problem follows lead its stator.