Mercury - Quicksilver Sea Water Pump Repair Kit Cooling System Component 2-Piece Plastic Pump 72774A89. Overview. If your cooling system is losing pressure or running weak, this Mercury Marine 72774A89 Quicksilver Sea Water Pump Repair Kit brings it back to life. Designed for 2-piece plastic body sea water pumps, this 6-piece OEM kit includes everything you need to rebuild your pump and restore steady water flow. Each part is made to Mercury's original specs, ensuring the same durability and per