90011-ZZ3-020 Head Cover Bolt - Overview. The 90011-ZZ3-020 Head Cover Bolt is a crucial component within Honda marine engine systems. This bolt secures the head cover to the engine block, playing a significant role in maintaining engine integrity and ensuring reliable operation. Engineered specifically for Honda marine applications, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Genuine OEM Honda bolt designed specifically for