Mercury - 225 Horsepower Rear Decal V8 Pro XS Series Marine Adhesive Finish 8M0217489. Overview. There's a certain satisfaction that comes with owning a Pro XS engine-the kind of quiet confidence you feel when you nudge the throttle forward and the boat just goes. When the cowling looks clean and the graphics are sharp, that feeling only gets stronger. Over time, sun and spray can wear down even the toughest decals, and suddenly the engine doesn't look quite as bold as it performs. This rear 225