Mercury - Check Oil Decal V6 & V8 FourStroke / Racing Series Marine Vinyl 8M0142570. Overview. Any seasoned boater will tell you that the small habits-like checking your oil-are what keep an engine running strong year after year. It is one of those quick, quiet moments before you push off from the dock, when you take a breath, glance over your equipment, and appreciate the machine that carries you across the water. The Mercury Marine part number 8M0142570 Check Oil Decal plays into that rhythm.