Yamaha - Outer Plate Cartridge Cooling System Component 6E5-44323-40-00. Overview. When you're working on a Yamaha cooling system, the small plates and housings are what keep everything sealed and flowing the way it should. This outer plate cartridge sits right where it needs to hold things together and keep water moving through the system without leaks or loss of pressure. Over time, these parts can warp, corrode, or just wear down from constant heat cycles. Replacing it helps keep your cooling system tight and doing its job, especially when you're running long or pushing the motor hard.. Key Features. Sealing Surface Design - Maintains proper sealing to prevent water leaks within the cooling system.. Corrosion-Resistant Construction - Built to handle constant exposure to water and marine environments.. Precision Fitment - Aligns correctly with mating components for proper water flow and pressure.. Direct Yamaha Replacement - Matches original specifications for straightforward install