13331-ZM7-000 Special Key - Overview. The 13331-ZM7-000 Special Key is a crucial Honda marine engine system component. This key functions as a Woodruff key washer supporting the engine's mechanical motion system. It plays a fundamental role in securing parts such as crankshafts by fitting precisely into corresponding slots, ensuring components rotate properly and maintain alignment under operational stress. Designed to integrate seamlessly with Honda marine engines, this genuine OEM part guarant