115 drops one cylinders

[carpenterken]

my 85 115 omc will one time start and run just fine and the next time start and run on 3 cylinders ( this will happen from one start to the next in the same day) It seams to only drop the cylinder from start up. I've had the carbs cleaned and new plugs put in. I'm thinking it could be a bad coil? Other than that it runs great.
What do you all think?

 

[jtexas]

Re: 115 drops one cylinders

you've narrowed it down and its the same cylinder every time?

compression test first, then spark test. no spark/bad spark, swap coils, if the problem follows the coil, replace it.