Mercury - Fuel Pump 2-Stroke DFI, Pro XS, Jet & SST Outboards High Pressure 855427A1. Overview. There's nothing quite like the sound of a Mercury two-stroke firing up - that sharp, confident growl that says your boat's ready to move. The Quicksilver 855427A1 Fuel Pump keeps that energy alive, delivering consistent, high-pressure fuel flow to your engine every time you turn the key. Designed for Mercury and Mariner 110-225HP 2-stroke outboards, this pump ensures smooth power delivery across the t