Yamaha - Water Pump Gasket Cooling System Seal 6CB-44315-00-00. Overview. Any time I'm in a lower unit doing a pump job, this is one part I don't reuse-no exceptions. The water pump gasket is what keeps everything sealed so the pump can build proper pressure and move water the way it should. Once it's worn or flattened out, you lose efficiency and sometimes don't even realize it until temps start creeping up. It's a cheap part that protects a much more expensive problem.. Key Features. • Leak-Free Seal - Creates a tight seal between pump components to maintain proper pressure.. • Heat Resistant Material - Holds up under constant temperature changes and water exposure.. • OEM Fit Accuracy - Matches Yamaha specs for proper alignment and sealing surface contact.. • Supports Pump Efficiency - Helps maintain strong and consistent water flow through the system.. Engine & Boat Compatibility. Verify compatibility with your specific Yamaha outboard model and part number before installation.. FA