Johnson Pump 09-701B-1 Impeller (MC97)

The Johnson Pump 09-701B-1 Impeller (MC97) is an essential replacement component for marine cooling systems that have experienced wear or damage over years of heavy use. Built to OEM specifications, this impeller kit restores proper coolant circulation to your engine's heat exchanger, preventing the overheating and potential engine failure that comes with a degraded pump. Whether you're running a saltwater-cooled inboard, a hard-working outboard, or any mid-sized marine powerplant, a failed impeller means your engine temperature climbs fast—and so does your repair bill if you ignore the warning signs.

Johnson Pump impellers are engineered for maximum flow rate and extended service life, using premium elastomer and composite materials that resist saltwater corrosion and UV degradation better than aftermarket substitutes. The flexible vane design creates a positive seal against the pump housing, maintaining consistent pressure across a wide RPM range and ambient water temperature. Genuine replacement impellers like the 09-701B-1 are developed through rigorous testing to match the original equipment's tolerance stack-up, ensuring you get factory-level cooling performance without the guesswork of universal or undersized alternatives.

This impeller suits skippers and boat owners who service their own cooling systems or rely on knowledgeable marine mechanics who stock Johnson Pump parts. Installation typically requires removal of the pump cover plate and a few minutes of work—no special tools needed beyond basic hand tools. If your engine runs hot, produces steam from the water intake, or you notice reduced water flow at the telltale indicator, the 09-701B-1 is a direct replacement that will bring your cooling system back to factory spec and get you back on the water with confidence.