Yamaha - Water Tube Cooling System Water Delivery 6E5-44361-10-00. Overview. Anytime I've had a cooling issue after a lower unit service, this is one of the first places I look. If the tube isn't lined up right or has any damage, you're not getting proper water flow up to the powerhead. It's a simple piece, but it plays a big role in keeping the engine temperature in check. When it's installed correctly, everything cools like it should and you can run with confidence.. Key Features. • Direct Cooling Water Transfer - Moves water from the pump to the engine for proper cooling.• Supports Stable Engine Temperature - Helps maintain consistent cooling under load.• Durable Metal Construction - Built to handle heat, vibration, and constant water flow.• Corrosion-Resistant Design - Performs reliably in both freshwater and saltwater conditions.• Exact Yamaha Fitment - Matches factory specifications for proper alignment and sealing.. Engine & Boat Compatibility. Designed for Yamaha outboard engin