Mercury - Quicksilver Engine Starter Planetary Gear Series Marine-Grade Build 8M6007409. Overview. Every boater knows the weight that settles in your gut when you turn the key and wait for that first crank. When your starter responds instantly-strong, clean, and sure-it sets the entire tone for your time on the water. The Quicksilver 8M6007409 brings that sense of calm and confidence to every launch. Whether you're warming up before heading into open water or easing away from the dock at sunrise