Yamaha - Water Cover Cooling System Component YF1-52617-39-10. Overview. On Yamaha cooling systems, even something as simple as a cover plays a big role in keeping everything sealed and flowing right. I've seen engines lose efficiency just from a warped or leaking cover that lets pressure drop off. The Yamaha Water Cover YF1-52617-39-10 helps keep that system closed up and working like it should. It's one of those parts you don't notice-until cooling performance starts slipping.. Key Features. •