Mercury - Block Water Pressure Digital Kit SmartCraft Pressure Input 8M0089111. Overview. Keeping an eye on cooling performance is a lot easier when your SmartCraft display shows block water pressure in real time. The Mercury 8M0089111 Block Water Pressure Digital Kit gives 2.1L F75-115 FourStroke engines the ability to send that pressure data directly into the SmartCraft network. It's a clean way to add an important piece of engine information without guesswork or extra steps at the helm.. Key