Impellers are critical to engine cooling, take a long a spare. Mercury outboards and MerCruiser sterndrive engines rely on the water pump for cooling. The impeller is the heart of the water pump; inspection and replacement is required on a regular basis to keep the engine running at optimum temperature. Quicksilver impellers give boaters and technicians the confidence of using an OEM part. Each impeller is engineered to original Mercury or MerCruiser specifications to provide a factory fit and restore function. Because impellers can be quickly damaged by running through silty or sandy water or by being run dry, we recommend having a spare aboard to be ready for unexpected failures. Available in many sizes for different engine applications, reference your repair manual or the table below to confirm the proper part number for your inboard or outboard engine. Or call 1-800 BOATING with your serial number, or make, model and year of your engine and speak to an expert to find the right impeller.