Yamaha - Water Tube Cooling System Component 6C5-44361-00-00. Overview. Cooling problems can sneak up on you, and a lot of times it comes down to something simple like water flow. This tube is what carries water from the lower unit up into the engine, so if it's restricted or out of place, the whole system suffers. I've seen overheating issues traced back to a bent or clogged tube more than once. Keeping this path clear and solid is key to keeping the motor running cool.. Key Features. • Direct Water Flow Path - Transfers cooling water from the pump to the engine efficiently.. • Maintains Cooling Performance - Supports steady temperature control under load.. • OEM Fit Accuracy - Matches Yamaha factory specs for proper alignment and installation.. • Durable Marine Construction - Built to handle heat, pressure, and harsh water conditions.. Engine & Boat Compatibility. Verify compatibility with your specific Yamaha outboard model and part number before installation.. FAQs. Q1: What are si