91251-ZY3-C01 Seal (26X42X7) - Overview. The 91251-ZY3-C01 Seal (26X42X7) is a crucial component in Honda marine engine systems. Designed primarily for the water pump vertical shaft, this seal prevents water and contaminants from leaking into sensitive engine sections, thereby ensuring smooth and reliable operation of the marine engine system. Its role is vital in maintaining the integrity and longevity of the water handling system within Honda marine engines. It ensures seamless integration wit