Yamaha - Outer plate cart. - 670-44323-00-00Yamaha Insert Cartridge Cooling System Component 670 44322 01 00 Overview This is one of those cooling system pieces that quietly does its job until somethings off. The insert cartridge helps guide water through the system, and when it starts wearing down or getting clogged, youll usually see it in higher temps or weak water flow. Ive run into plenty of cases where swapping this out brought the cooling system right back to normal. Its a simple part,