Mercury - Quicksilver Serpentine Belt 2,240mm For MerCruiser Sterndrive & Inboard Engines 807755Q04. Overview. A worn or cracked belt can mean the difference between a smooth day on the water and an unexpected breakdown. The Mercury Marine 807755Q04 Quicksilver Serpentine Belt is a 2,240mm OEM replacement, designed to keep your MerCruiser sterndrive or inboard engine performing just like it did the day it left the factory. This belt drives essential systems like your alternator, power steering p