Mercury - Water Pump Impeller Cooling System Component Flexible Marine Elastomer 89980. Overview. If you've ever run a vintage Mercury outboard, you know there's a certain charm in those small horsepower engines - the quiet idle, the steady push, the simplicity. But one thing hasn't changed over the decades: a dependable water pump impeller is absolutely essential. The Quicksilver 89980 Water Pump Impeller brings new life to classic 3.5-9.8 horsepower Mercury 2-stroke engines, helping them stay