IMPULSOR 47-84027

Function and technical context

The 47-84027 impeller is the heart of the water cooling system in Mercury marine engines, responsible for pumping water from the outside into the engine's internal circuit to maintain optimal operating temperatures. This part works inside the centrifugal cooling pump, propelling the cooling fluid through the engine jacket and heat exchangers through forced circulation. Its correct operation is critical to avoid overheating of the propeller, which could cause irreversible damage to joints, cylinders and lubrication systems, compromising the safety and availability of the vessel in navigation conditions.

When to replace this part?

The impeller shows signs of wear when there is a noticeable reduction in the cooling water flow, an abnormal increase in the engine temperature indicated on the instruments, audible cavitation in the cooling pump or the presence of mineral deposits on the vanes that reduce their hydraulic efficiency. It is recommended to check and replace the impeller every 300 to 400 hours of operation or at least once per boating season, especially if we operate in waters with high sediment or salinity content that accelerate wear. Performing this replacement preventively is the most economical strategy to avoid complete engine failure in navigation conditions far from port.

Equivalent manufacturer part numbers