Your car's water pump is one of the most important parts your car has. It is the part that continually pumps water and coolant to your vehicle's engine so that it doesn't overheat. The water pump is a simple centrifugal pump driven by a belt connected to the crankshaft of the engine. The pump circulates fluid whenever the engine is running. The water pump is the primary part of the cooling system. The pump circulates coolant between the engine and radiator to keep the engine from overheating. The water pump is usually belt driven and is mounted on the front of the engine.

Water pumps typically fail one of two ways: the shaft seal starts to leak, or the impeller inside breaks comes loose or the blades erode and wear down. When a water pump starts to leak, the cooling system will lose coolant. If the leak is not discovered, the loss of coolant will eventually cause the engine to overheat. The drive may not realize anything is wrong until the temperature warning light comes on. If the engine has overheated, the entire cooling system (radiator, hoses, water pump and engine) must all be inspected to see if there are any coolant leaks. If coolant is leaking out of the water pump shaft or vent hole, the water pump needs to be replaced. Sometimes a water pump will fail internally due to severe corrosion wearing away the impeller blades, or the impeller comes loose on the shaft, or the shaft itself may break from metal fatigue . One way to test for a bad water pump is to squeeze the upper radiator hose when the engine is hot and idling.

Careful, because the hose will be hot, If you do not feel much coolant circulating through the hose when you rev the engine, the pump may be bad. The other cause might be a bad thermostat that is not opening properly (remove and inspect the thermostat), or a clogged radiator. A leak in your water pump or a faulty bearing can cause serious damage to your car's engine. As a car owner, you must be on the lookout for malfunctions that require repairs or replacement. Puddles of coolant or water underneath your vehicle or high temperature readings may be signs that your water pump needs replacing. When it comes to water pump longevity, they actually tend to last a long time. It's recommended that your engine's water pump be replaced when the timing belt is serviced. o avoid running into the problem of a failed water pump, there are a couple warning signs that you can look for. The first is if coolant is leaking around the water pump. Weep holes located on the casing of the water pump will leak coolant when the pump is failing. The second red flag is if the water pump is making more noise than usual. It's unlikely that you'll have to diagnose your car's water pump problems yourself, but just remember it's always a good idea to have your water pump replaced when your vehicle's manufacturer recommends changing the timing belt.  While many motor vehicle engine repairs can be spelled out in a simple step-by-step format, a water pump replacement is not one of them. This is because there is so much variety in the placement of and access to water pumps between vehicles, no one simple set of directions may be applied to all vehicles. So you'll have to follow your particular manual here.