Mercury - Quicksilver 8M0220181 Spark Plug Wire Kit MerCruiser 496/8.1L Series Marine-Grade Ignition 8M0220181. Overview. When you spend a lot of time on the water, you learn to appreciate the small parts that quietly keep everything running. Spark plug wires aren't flashy, but when they're working right, you feel it - steady idle, strong mid-range pull and the confidence that your boat will fire up the moment you twist the key. The Quicksilver Spark Plug Wire Kit 8M0220181 is one of those piece