Hey guys, i have a 23 hp beavertail longtail. Bought it brand new. Has about 20 hours on the engine. Motor runs fantastic until i hit roughly 80-100% throttle. It will then run for about 30-40 secs and will then beginning to slowly drop rpms until it sputters out and dies. If i pump the primer bulb on the fuel line just once every 20-30 secs the engine runs fine and rpms stay high. I have made sure that all fuel lines are clamped tight and that the tank is venting properly. Wondering if any of you have had this issue or have anyodeas where i could start? Thanks

Obvioiusly you have an air leak between the tank and motor.
Could be in the hose lines, or intake gasket on the motor.

Ok thanks i will check the lines and start there

Also, unplug the hose going from the Fuel pump to the carb, and crank your engine. It should spit out fuel. Just to confirm your fuel pump is working properly. But if your motor is able to get to WOT, I'm sure your fuel pump is fine.
Any bubbles in your fuel filter?

Those symptoms are representative of not getting enough fuel to the carb and eventually the bowl empties faster than it is filling up. If you let off the throttle some, does it stop dropping rpms? The bulb is topping off the bowl, eliminating the problem of it going dry. Is your fuel tank vented properly? Could also be a bad fuel pump. Regardless, your fuel pump isn't keeping up with demand once you get above 80% throttle. Maybe it's just the bad apple, as it's not typical for a fuel pump to go out at 20 hours but has been known to happen.

Change fuel filter, and if you have one, the water separator.