Mercury - Quicksilver Alternator Marine Charging System Corrosion-Resistant Finish 8M6007509. Overview. There's a moment every boater knows well-the quiet hum before the engine fires, the tap of waves against the hull, and the feeling that everything onboard is ready to go. A dependable alternator is one of those behind-the-scenes parts that makes that confidence possible. The Quicksilver 8M6007509 alternator brings that sense of certainty back into your trips, delivering steady power for engine