May be a stupid question, but can you do this, much like adding oone to the gas of your automobile?

If so, is there any particular brand that works best?

Thanks for the help.

Bowjunkie:

I use Berryman's B-12 in my first tank of gas every Spring. I've had good luck with it. Available at Wal-Mart. I also use the B-12 spray carb cleaner when I've rebuilt carbs following mechanical failure of the float or float spring. Don't use a plastic measuring device with this stuff, it will eat it almost instantly. I'm also careful to follow the warning on the can that says "Not for internal use....harmful if swallowed"........gotta love lawyers.

i use amsoil powerfoam in the spring ,just spray a whole can in the carbs . i also use it in my auto's

RingFree and SeaFoam are both made especially for outboards.  I always add RingFree to my tank with every fillup.

Thanks! I know where I can get seafoam, but how about ring free? And have you ever had this stuff improve a rough running engine due to dirty carbs? I am not sure if that is what is going on or if I have water in the fuel. I am getting hesitation big time when at WOT. Idles great, but when you punch it, it sometimes dies and then when you do get up on plane, it runs balls out for a second, then starts bogging down. I can normally run 67 with this boat and I am lucky to hit 45 because of the fuel situation.

Bowjunkie35-  Had a similar situation with a carborated '86 Yamaha 150-  It may be a powerpack issue you're describing.  However, gasoline added cleaner and fresh plugs will only help the preformance of your motor.  My .02