40114-ZV5-821 Case (Lower) Grom - Overview. The 40114-ZV5-821 Case (Lower) Grom is a critical component in Honda marine engine systems, specifically supporting the engine lower casing assembly. This grommet functions primarily to provide effective sealing and vibration dampening where the lower engine case connects to surrounding parts. Engineered for precise integration, it ensures seamless operation and longevity of the marine engine by preventing water intrusion and minimizing mechanical wear