Yamaha - Cartridge Insert Cooling System Component 6R3-44322-40-00. Overview. This is one of those parts that quietly keeps your cooling system doing its job. I've seen engines run hotter than they should just because an insert like this was worn or partially blocked. When it's in good shape, water flows where it needs to and the motor stays consistent, even on long runs. It's not flashy, but it's critical to keeping things reliable on the water.. Key Features. • Controlled Water Flow Path - Helps direct cooling water efficiently through the system.• OEM Precision Fit - Matches factory dimensions for proper installation and sealing.• Corrosion-Resistant Build - Designed to handle constant exposure to marine conditions.• Supports Stable Engine Temps - Helps maintain consistent cooling performance under load.. Engine & Boat Compatibility. Designed for Yamaha outboard engines with internal water cooling systems. Commonly used across a range of Yamaha outboards where proper water flow and