Yamaha - Water Pump Repair Kit Cooling System 6L2-W0078-00-00. Overview. On these mid-size two-stroke Yamahas, keeping the water pump in good shape is just part of staying ahead of bigger problems. Once water flow starts dropping off, it doesn't take long before you're dealing with overheating. This kit is the kind of service job I recommend doing before issues show up, not after. It's a solid, complete refresh that gets the cooling system back to doing its job without guesswork.. Key Features. Complete Pump Service Kit - Includes key components needed to restore proper cooling system performance.. High-Quality Impeller - Provides strong and consistent water flow through the engine.. Precision-Matched Components - Designed to work together for proper fit and reliable operation.. Includes Seals and Hardware - Comes with O-ring, bolts, and key parts for a thorough rebuild.. Durable Marine Construction - Built to handle constant exposure to water and harsh conditions.. Engine & Boat Compa