Mercury - Alternator 140 Amp Charging System Marine-Grade Build 8M6007513. Overview. When you run big electrical loads-trolling systems, pumps, radar, lighting, or entire industrial rigs-you need an alternator that never quits on you. The Quicksilver 8M6007513 Alternator is built for those long days when the engine hums for hours and every accessory depends on a consistent, trustworthy charge. Whether it's powering a commercial vessel, a workboat, or a heavy-duty marine engine that's part of you