40109-ZV4-010 Oil Case Grommet - Overview. The 40109-ZV4-010 Oil Case Grommet is a vital sealing component in Honda marine engine systems. It plays a crucial role in preventing oil leaks within the engine's oil case, assuring the engine runs smoothly and efficiently. Designed specifically for Honda marine engines, this grommet provides a durable, factory-accurate seal that integrates seamlessly with the oil case and surrounding hardware, maintaining system integrity and performance.. Key Feature