How Does an RV's Water Pump Work?

Pressurizes Engine Water

  • The main function of an RV's water pump is to pressurize stored engine water and pump it directly into the engine. The water pump is an integral part of an RV's cooling system, which also includes the radiator and assorted hoses. The water pump is made up of a small inner propeller surrounded by a metal housing that bolts directly to the engine block. The spinning motion of the propeller creates the pumping action of the water pump.

Water Pump Pulley and Drive Belt

  • Attached directly to the front of an RV's water pump is a small pulley mechanism on which the water pump drive belt rides. This pulley is attached directly to the inner water pump propeller; the drive belt fits snugly onto the pulley and is responsible for providing the spinning action that powers the water pump propeller. An Rv's water pump would be non-operational without its pulley and drive belt mechanisms.

Water Pump Size

  • Water pumps come in a variety of sizes. Larger vehicles with larger engines and/or vehicles designed for heavy-duty use typically come installed with larger water pumps. An RV is a large, heavy vehicle that is normally used for long-distance driving combined with large-scale towing applications. This mandates the use of a larger, more powerful water pump to handle the increased operating temperatures and strains of a recreational vehicle.

Water Pump Hose

  • A large, rubberized water pump hose supports the function and use of an RV's water pump. This hose, which is heat resistant and responsible for funneling pressurized water from the water pump directly into the engine radiator, is a vital link in the overall cooling system of an RV. A leaky or malfunctioning water pump hose can cause overheating, radiator failure and engine damage.