Keep your Mercury outboard running smoothly with this complete Lower Unit Seal Kit!

Designed for 20 HP models with serial numbers between 4709593 and 6443972, this kit replaces OEM part #26-66303A1 and matches WSM/Sierra #18-2627.

Inside, you’ll find high-performance gaskets and seals that meet or exceed factory standards—perfect for preventing leaks and protecting your lower unit from water damage.

At PWC Engine, we use top-quality materials like Athena USA gaskets and ARS precision seals, so you can trust this kit to hold up under pressure.

Whether you’re a DIY boat owner or a professional mechanic, this seal kit makes maintenance easy and affordable.

Remember: Mercury motors aren’t identified by year, so double-check your serial number before ordering.

Get back on the water with confidence—this kit has everything you need for a reliable seal job!