40113-ZVD-300 Case (Lower) Seal C - Overview. The 40113-ZVD-300 Case (Lower) Seal C is an essential sealing component within Honda marine engine systems. It plays a pivotal role in maintaining a secure seal in the lower case assembly of the marine engine, preventing water ingress and protecting internal components from damage. Designed to Honda's stringent factory specifications, this seal ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Feat