150 surging

[mikedan1]

I have a 2002 carburated 150. Last season it started surging above 3800rpm. I changed the 10 micron filter , everything seamed ok but started again. This season i changed all the filters and put it in the water engine was running great, last week it started surging again so I changed both fuel pumps and primer. It ran all the way to 5100rpm. Yesterday it started surging again so i pumped the ball while it was surging, it stopped when I pumped the ball, so I think the carbs need to be cleaned, i have done car and motorcycle carbs before, how hard is it to do on an outboard? I dont want to change the settins because there are 3 of them.

[boats.net]

It could be a restriction in fuel line or an air leak in fuel system, try running on a portable gas tank connected to engine fuel filter to eleminate boat fuel system.