Yamaha - Water Tube Cooling System Water Transfer 6AW-44361-00-00. Overview. This is one of those parts you don't see unless you're deep into the motor, but it's critical to keeping things cool. The water tube is what carries cooling water from the lower unit up into the powerhead, and if that flow gets interrupted, you'll know it fast. When it's straight and sealed properly, everything works like it should. But if it's bent, blocked, or not seated right, you're risking overheating without much warning.. Key Features. Direct Water Delivery Path - Moves cooling water efficiently from the lower unit to the engine.. Precision Fit Alignment - Designed to seat correctly between components for uninterrupted flow.. Corrosion-Resistant Build - Holds up against constant exposure to water and marine conditions.. Cooling System Reliability - Helps maintain steady engine temperature during operation.. Engine & Boat Compatibility. Designed for Yamaha outboard engines using this style of internal wa