Yamaha - Water Tube Cooling System Component 6J8-44361-00-00. Overview. The Yamaha Water Tube 6J8-44361-00-00 is one of those parts that keeps your engine cool without you ever thinking about it-until something goes wrong. When this tube starts to clog or wear out, you'll usually see it in higher temps or weak water flow. It's responsible for directing cooling water through the engine, so it has to stay clear and properly seated. If you're chasing an overheating issue or refreshing the cooling system, this is a smart part to replace.. Key Features. • Efficient Water Routing - Directs cooling water through the engine to maintain proper temperature.. • OEM Fit Precision - Matches Yamaha specifications for proper alignment and secure installation.. • Corrosion-Resistant Build - Designed to handle long-term exposure to water and harsh marine conditions.. • Supports Engine Protection - Helps prevent overheating and protects internal engine components.. Compatibility. Compatible with select