115 missing on 2 Cyl.

[TripleB]

Hello

I just purchased a 1984 115 mercury, seemed to be running great till I mounted it on the boat and put it in the water then the trouble started ..... lol

So anyhow when I put the boat in the water and had no hole shot at all ...... So after a lil reading I had it on the muffs and pulled off 1 plug wire at a time .... what I found out is that its not firing on cylinders 1 and 3 witch sure fooled me cause it sounds like it running great and not stumbling at all! .... So ..... where should I start looking first? Im fairly mechanically inclined but never worked much on electronics. Was think that it missing on those cylinders might help as where to look first? ........ any help would be greatly appreciated

Here's whats been done.

Comp test ..... all 6 between 125-130
Carbs cleaned
Fuel pump rebuilt
New impeller

TY in advance
TripleB

 

[Charlie61]

Re: 115 missing on 2 Cyl.

think it may be switch box, you have two them. check to see if you are getting voltage to coiles of switch box, if the top one is miss firing beleve it runs 1,3,5, and lower one 2,4,and 6 ,if one of the three work from switch box it may be bad, so you need to see if voltage is getting to switch CDI electros that will help you