87 johnson 30 hp fuel or electrical

[loopy]

"I have a problem when i run a

"I have a problem when i run at 1/2 - full throttle the motor sounds like it has a bad miss. but only intermitent, it will run out for a few hundred yards then it starts for a second or two then runs ok for another little bit and does it again and so on , the longer i hold it open the worse it gets at an idle it seems ok, I have had the carb rebuilt and new plugs put in as well as a fresh tank of fuel to no avail. any suggestions Fuel pump maybe ? Coil ? Timing ? dont know where to go from here.Any help would be very appreciated.
Regards Ken"

 

[jwbmarine]

"first,find out,which cyl,is c

"first,find out,which cyl,is causing ur prob...and research,fr there..."

 

[lorddrek]

I had this problem on a 72 Evi

I had this problem on a 72 Evinrude 50hp and it quickly got worse to the point where it was running on one cylinder at all speeds. Swapped out the bad coil with a spare and it was fine.