40105-ZW9-830 Oil Case Grommet A - Overview. The 40105-ZW9-830 Oil Case Grommet A is a specialized rubber seal designed for Honda marine engine systems. This part plays a crucial role in preventing oil leaks within the oil case, ensuring the marine engine's internal components are securely sealed. By maintaining proper sealing, it supports the engine's reliable operation and longevity. Manufactured to meet exact factory specifications, it ensures seamless integration with existing parts, maintai