2002 25hp 2 stroke misfire

[chocko456]

Hi all,
I have a 2002 25hp 2 stroke single carb outboard ,model number 25BMH (Australian ) . The motor starts easy but idles a bit rough, when accelerating from start it misfires ( sounds like its 4 stoking ) until about 1/4 throttle then runs great up to WOT . I have checked the timing, fitted new plugs and cleaned and rebuilt the carby with no change . I am thinking pulser coil . I am waiting for a new meter to arrive so i can test the coils but i am keen to see what the brains trust on this forum come up with. Thanks, Chocko.

[99yam40]

have you checked the fuel pump?
if leaking into crankcase it will/could cause a rich condition at low RPM

[chocko456]

Quick update . Carby fuel inlet valve seat was corroded allowing excess fuel into the bowl and slightly flooding the engine at idle . New seat and all is good . And a fuel tank clean out. Thanks 99yam40 you were on the right track about excess fuel but from a different place , it was four stroking.

[donsmarine]

what is 4 stroking?

[99yam40]

what is 4 stroking?

not firing on every revolution like a 2 stroke should

[Thorsen123]

Hi i have the same problem on my 25hp. It misfire on low rpm but works great on high rpm. How did you fix it?

[TownsendsFJR1300]

Hi i have the same problem on my 25hp. It misfire on low rpm but works great on high rpm. How did you fix it?

From post #3: . Carby fuel inlet valve seat was corroded allowing excess fuel into the bowl and slightly flooding the engine at idle . New seat and all is good . And a fuel tank clean out.