23172-ZY3-003 Mount Case Gasket - Overview. The 23172-ZY3-003 Mount Case Gasket is a vital component in Honda marine engine systems. It supports the mounting system by providing a watertight seal for the mount case, preventing leaks that can damage internal engine parts. Reliable sealing ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Precisely designed as a genuine OEM gasket ensuring accurate fit and factory specifications.. Prov