17398-ZW1-000 Muffler Drain Joint - Overview. The 17398-ZW1-000 Muffler Drain Joint is a critical component of the Honda marine engine exhaust system. It facilitates the effective draining of water and other fluids that accumulate in the muffler, thereby preventing corrosion and system blockages. Designed specifically for Honda marine engines, this joint helps preserve the engine's performance and longevity. Its integration ensures seamless compatibility with existing Honda exhaust hardware, mai