Mercury - Quicksilver Quick Disconnect Fuel Line Fitting Fuel System Component Brass and Composite 13563Q3. Overview. The difference between a smooth-running engine and a sputtering one often comes down to fuel delivery. The Mercury Marine 13563Q3 Quicksilver Quick Disconnect Fuel Line Fitting keeps that connection tight and dependable where it matters most - at the engine end of your line. Designed for Mercury, Mariner, and Force outboards, it locks into place with a confident click and stays s