Frustrating day on the water.
Just got a "new to me" 25 Kohler longtail and took it out on the water- it would not run right.

Fuel filter, lines and tank are all new.
My Mower/outboard guy cleaned the carb and lubed it all up.
It runs great in the yard.

On the water I turn it on- hear the fule pump clicking. pump the ball, pull the choke, and crank it up.
It runs fine for 20 feet the sounds starved for gas and dies.
I choke it, pump the bulb and it starts again.. runs a little and dies.

Not throtteling it full out makes the motor run a little longer
And putting a load on it makes it stall quicker.

To make things more confusing- it ran poor yesterday on the way to the blind, Great yesterday back to the ramp and then crappy all day today.

I'm taking to my mechanic tomorrow but I just don't know where to start.

do you have one of those flat mikuni fuels pumps with the diaphragm if so try changing that my 16 did that and i changed carb fuel lines tank and everything and it didnt do right until i changed that pump the guy at the shop told me the diaphragm dries out from sitting up so they need to be changed if it sits up for a couple months

mine did the same thing. change the diaphram pump and all is well in the world