Mercury - Quicksilver Black Fuel Line General Purpose Fuel System Black Polymer 8M0108355. Overview. There's something reassuring about the simple parts on a boat - the ones you barely notice because they just work. A good fuel line is one of those quiet essentials. You can feel the difference when everything is flowing the way it should: the engine fires up clean, the throttle responds smoothly, and the whole ride feels steady. This Quicksilver Black Fuel Line gives you that kind of confidence,