94 mercury 30hp double firing

[wmihardwoodfloors]

I have a 94 mercury outboard elpto that is sparking multiple times per revolution. Both cylinders are doing this. The outboard actually will run backwards when it backfires. I figured that it was a trigger issue so I replaced it. No change. Could it be the flywheel magnet? Running out of ideas.

 

[FWDan]

I also have a multiple firing per revolution problem and I'm trying to isolate the cause. Since trigger was not your problem, did you ever find a solution?

 

[CharlieB]

FWDan please start a new thread. List your motor info and how you determined what your problem is. You will get a response.

The V6's ADI dual switchbox system has a possibility of double firing if a blocking diode in one switchbox is defective. The factory recommends replacing BOTH switchboxes even though only one has the defective diode. BOTH switchboxes will work perfectly fine on any of the three cyl motors so mark then 'Bad Bias' and sell to 3 cyl owners needing a replacement switchbox.

Remember there is NO RETURN on electrical parts. You must PROVE the part bad before ordering any spendy new parts.

Post that new thread and we will work your way through it to be certain of the problem cause.