Yamaha - Water Pump Repair Kit Cooling System Service Kit 63V-W0078-04-00. Overview. Cooling system service is one of those things you don't put off on a Yamaha outboard. The Yamaha Water Pump Repair Kit 63V-W0078-04-00 bundles the key wear components needed to restore proper water flow through the engine. When impellers get stiff or wear plates groove over time, water pressure drops and overheating risks climb. A complete pump refresh like this brings the cooling system back to full strength so