DF 6 Accelerates while at idle

[Duncan]

My one year old DF 6 will begin to accelerate after having been in neutral for more than an minute or two.

The engine will return to a slow idle speed if i pull the choke out half way and then push it back in. Then in a minute or two it starts to high idle again.

The idle gets so high that changing from neutral to forward with out using the choke to go back to slow idle causes a loud bump and stress on the engine.

Suggestions are appreciated.

Duncan

[boats.net]

Could have an air leak at the carburetor or intake. Try adjusting the idle screw.