Mercury - Inlet Needle Valve Carburetor Fuel Control Precision Marine Alloy 879194011. Overview. If you've spent enough time around small and mid-horsepower outboards, you already know how much of a difference a well-behaved carburetor can make. A clean, steady idle… a smooth rise onto plane… crisp throttle response when you need to dodge a crab pot at the last second. It all comes down to tiny parts doing their jobs without hesitation. The Mercury Marine 879194011 Inlet Needle Valve is one of t