Yamaha Oil Seal S-Type Lower Casing - 93101-28M16-00. The small ring that keeps your gear-case healthy is the Yamaha S-Type Lower-Casing Oil Seal (93101-28M16-00)-precision-cut to 28 mm ID × 43 mm OD × 7 mm wide for the driveshaft pocket on dozens of Yamaha V-6 and inline-four outboards. Pop this fresh seal into the carrier and you lock water out, lock gear lube in, and spare yourself the cost of a full lower-unit rebuild.. Molded from fuel- and oil-resistant NBR rubber, the seal stays supple even after seasons of hot running and salt-spray storage. A stainless-steel garter spring hugs the shaft, while the S-type dual-lip profile clears micro-debris without letting seawater sneak past.. Why it deserves space in your toolkit. Exact OEM fit-drop-in replacement for Yamaha part 93101-28M16-00; no trimming or shimming required.. Double-lip design for twice the barrier against emulsified lube and corrosion.. Marine-grade materials-UV-stabilized rubber and stainless spring laugh at salt and h