63102-ZW1-300 Engine Cover Seal - Overview. The 63102-ZW1-300 Engine Cover Seal is a critical component in Honda marine engine systems. This rubber gasket creates a secure, watertight seal between the engine cover and the engine block, playing a vital role in protecting your engine from water intrusion and debris. Designed specifically for Honda outboard marine engines, this seal helps maintain optimum engine performance and longevity by ensuring the engine's internal components remain protected