How Your Engine’s Water Pump & Cooling System Works

Understanding how your vehicle’s water pump works might best be done by thinking of it as the “heart” of your car’s cooling system. Its primary function is to constantly circulate engine coolant through the cooling system from the radiator to the engine and back.  The water pump consists of an Impeller, a Pulley Flange and an O-Ring. The impeller is driven by the engine drive through a pulley.

Your vehicle’s engine directly supplies power to the water pump…allowing it to work properly. Usually power is delivered from the simple combination of a belt and pulley, but there are some cases (less often) that a water pump operates via a gear and chain. The power that the pump generates from the engine is transferred to a shaft on which there is an impeller.

The impeller’s purpose is to spin and circulate the coolant throughout your car. It’s similar in function to the way that a propeller makes a boat or airplane move forward.  The shaft and impeller spin together on a sealed bearing. This sealed bearing is the part of the car’s water pump that eventually wears out, so you must be vigilant in watching for to break down.  Visibly leaking coolant is the tell-tale sign to help you know it’s happening (or about to).  Also, an unusual noise…a metal-to-metal grinding sound (usually due to lack of lubrication) is an indicator that the bearings inside the pulley are already faulty or about to wear out.  A wet engine or a coolant sob through your car’s vent are also signs that your water pump may be going bad.

If you notice any of these signs, it’s time to get your water pump replaced. Generally, a water pump is either working or it’s not.  Here’s a wise consideration.  Whenever you radiator is being replaced or removed for whatever reason…it’s a very smart and practical time to replace your water pump. Why? Because often times surrounding systems have to be removed anyway…just to get to the water pump, which adds time, labor costs and hassle.

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