Mercury - Quicksilver Exhaust End Cap Riser Gasket PCM Ford 302 & 351 Replacement Marine-Grade Sealing Component 8M0162540. Overview. There's a special kind of respect that grows between a boater and an inboard engine over the years. These engines have a heartbeat of their own, and when they're looked after properly, they reward you with smooth mornings, reliable pulls and steady performance through rough patches. The Mercury Marine part number 8M0162540 Exhaust End Cap Riser Gasket brings that