Mercury - Oil Change Kit, 40/50/60HP EFI FourStroke, 3 Liters Maintenance 8M0081916. Overview. The 40-60HP Mercury EFI FourStroke engines are workhorses-fishing, cruising, towing, long idle sessions, you name it. They run cleaner and last longer when the oil is fresh, and this kit makes the whole job straightforward. Three bottles of the right oil, the proper filter, a new drain plug seal, and a drip tray so you're not wiping up after yourself. If you've ever changed oil with the motor tilted up