Yamaha - Insert cartridge - 689-W4432-02-00Yamaha Water Pump Cartridge Insert Cooling System Component 689 W4432 02 00 Overview When youre doing a water pump service, this insert is one of those pieces that can make or break the job. Even with a fresh impeller, a worn insert will hold you back on water flow. Ive seen guys skip it and still deal with weak cooling after a rebuild. Putting in a new Yamaha insert helps everything move water the way its supposed to. Key Features Optimized Water