Mercury - Sea Pump Kit Cooling System Component Marine-Grade Construction 8M0139996. Overview. Most of us who spend real time on the water know that engine cooling is one of those things you rarely think about-until the moment you have to. That is why having a dependable, factory-built sea pump gives such a sense of calm. The Mercury 8M0139996 Sea Pump Kit delivers that quiet reassurance every boater wants, especially when you are running through choppy inlets or easing away from a crowded marin