Mercury - Quicksilver 8M6007504 Alternator Volvo Penta / Marine Applications 24-Volt / 55 Amp 8M6007504. Overview. Every boater knows that dependable power isn't just a convenience-it's the backbone of a safe day on the water. When your alternator is working the way it should, you feel it in the quiet confidence of your gauges, the steady glow of your electronics, and the peace of mind that comes from knowing your system is charging like it's supposed to. The Mercury Marine part number 8M6007504