13621-ZZ3-000 Pulley (19T) - Overview. The 13621-ZZ3-000 Pulley (19T) is a critical component designed for the timing belt drive system in Honda marine engine systems. Its primary role is facilitating the smooth and precise transmission of mechanical power within the engine due to its 19-tooth gear design. Engineered specifically for Honda applications, this pulley supports the overall reliability and efficiency of your marine engine. Manufactured to exact factory specifications and tolerances,