Mercury - Exhaust Seal V12 Verado / SeaPro Series Silicone 8M0177471. Overview. When you run a Mercury V12, you expect nothing less than absolute confidence every time you throttle up. These engines aren't just powerful - they're refined, smooth, and built to perform long after the sun sets on another day offshore. The Mercury 8M0177471 Exhaust Seal plays a small but crucial role in keeping that experience intact. It prevents exhaust leaks that can quietly sap power, affect efficiency, and throw