Mercury - Bearing Carrier Seal Bravo III & Blackhawk Sterndrive Series Marine-Grade Sealing Component 861694. Overview. When you spend your weekends on the water, you learn quickly that the parts you never see often matter the most. A solid bearing carrier seal is one of those quiet heroes inside your drive-working constantly, keeping gear oil where it belongs, and keeping water far away from the internal components that power your boat. Mercury Marine part number 861694 is built for that exact