36135-ZY6-003 Check Valve - Overview. The 36135-ZY6-003 Check Valve is an essential component within Honda marine engine systems, primarily supporting the fuel system. It plays a crucial role in maintaining reliable operation by regulating fluid flow, allowing it to travel in only one direction to prevent backflow. This check valve is vital for preserving the integrity and efficiency of the fuel or oil lines within your marine engine, ensuring smooth and trouble-free performance.. Key Features.