Mercury Marine Outboard Water Pump Kits

Outboard water pumps are simple designs. The pump draws water through the intakes and up into the housing.

The impeller blades (vanes) touch the liner at lower speeds as the driveshaft turns, but as the engine revs up, the impeller blades bend back away from the housing liner. Typical water pump kits includes the following: bearings where applicable, rubber seals, mechanical water pump seal where applicable, side cover gasket, water pump gasket, snap rings located on water pump shaft, and copper drain washers. It's good outboard maintenance practice to check your water pump impeller every season, and replace it every two to three seasons. 300 hours of use or every 3 years whichever comes first! How to tell if a water pump is bad: the outboard motor is overheating, the impeller is living on borrowed time, there is a reduced stream of water from the cooling water outlet. The pump sends out water from the top of the housing with a brass tube. This travels up through the engine's power head, ensuring it circulates into the cooling passages of the engine. The water pump kit comes with all the parts necessary to fix any water pump issues.