Mercury - Carburetor Gasket Set Fuel System Component Composite Gasket Material 9651. Overview. Any boater who's spent time with an older two-stroke knows that the carburetor is the heart of the engine's personality. When the gaskets start to give out, you can feel it-rough idle, a bit of fuel seepage, maybe a sputter when you try to push the throttle forward. That's when a fresh, dependable gasket set makes all the difference. The Quicksilver 9651 Carburetor Gasket Set brings your 40hp Mercury