Yamaha - Diaphragm Fuel Pump System 6E5-24471-01-00. Overview. This is one of those parts you don't see working, but you definitely notice when it stops doing its job. The diaphragm keeps fuel moving through the pump with every pulse of the engine, and once it wears out, performance drops off fast. I've seen engines go from running fine to struggling at idle just because this piece got stiff or cracked. Replacing it is a simple way to bring back steady fuel flow and dependable running.. Key Features. Responsive Fuel Pump Action - Flexes with engine pulses to move fuel consistently through the system.. Durable Rubber Construction - Built to handle repeated movement and long-term fuel exposure.. Maintains Engine Stability - Supports smooth idling and steady throttle response.. Exact Fit Replacement - Designed to match original specifications for proper sealing and installation.. Engine & Boat Compatibility. Designed for Yamaha 2-stroke outboard engines equipped with diaphragm-style fuel