Yamaha - Water Pump Repair Kit Cooling System 6E0-W0078-A2-00. Overview. When you're servicing the water pump on these smaller Yamahas, it's usually best to just do it all at once. I've seen too many cases where only the impeller gets replaced, and the rest of the worn parts end up causing issues not long after. A full kit like this takes care of everything in one go and saves you from opening it back up again. Once it's done right, you get solid water flow and peace of mind every time you head out.. Key Features. Complete Pump Rebuild Kit - Includes all major components needed for a full water pump service.. Restores Cooling Efficiency - Helps bring water pressure and flow back to proper operating levels.. Matched Internal Components - Designed to work together for proper fit and consistent performance.. Durable Marine Construction - Built to handle heat, friction, and debris in real-world conditions.. Engine & Boat Compatibility. Designed for Yamaha 2-stroke outboard engines using st