125 hp running rough

[JBThompson]

I have a 94 mercury 125 hp. The motor recently started running really rough between 1500-2000 RPM. At 1400rpm sounds great. At 2100 feels great. I know that somewhere in that RPM range it goes from 2 cylinder to 4 cylinder. When I say rough I mean rough. She vibrates the whole boat and acts like it wants to die but never does. Anybody have any ides as to what this could be? Thanks for any input. I've pulled the carbs for a full rebuild,Replacing all fuel lines/filters,going to decarbonize with seafoam.

 

[JBThompson]

Please help!!!!

 

[pigeon laker]

Check the Accelerator pump.It's does most of it's job in the transition from 2 to 4 cylinder.

 

[JBThompson]

will do thanks.