The water pump is a core part of your car's cooling system. It is responsible for circulating coolant from the engine compartment to the radiator. As a new car owner, it's important that you understand how the water pump works and the early signs of failure. The sooner you can identify a malfunction, the more likely it is that you can prevent an overheated engine.

Water Pump Basics

Water pumps are typically belt-driven and mounted to the front of the engine so that the belt can run across the engine pulleys. The pump itself contains an impeller with blades that push the coolant through the pump. The impeller blades are usually made from plastic or metal.

Common Water Pump Problems

There are two common ways that water pumps can fail. It's important to understand the signs of pump failure so that you can catch these problems before your engine overheats and causes costly damage.

1. Seal Leaks: The shaft that connects the water pump to the impeller has a seal and bearing that is supposed to seal it and prevent coolant from seeping past the bearing. If coolant seeps around the bearing, it can cause substantial coolant loss over time. Although the seals are durable, they're not completely impervious to wear. In fact, sediment, rust and contaminants in the system can damage the seal and lead to leaks. Monitoring the level of coolant in the radiator and watching for leaks under the car are the best ways to spot a leaking seal.   
2. Impeller Damage: Another common issue with water pumps is impeller damage or complete failure. If the water pump is fitted with a plastic impeller, the coolant can actually erode the plastic. If the impeller stops running or isn't able to push coolant through the system, it will lead to overheating. Impeller problems can be more difficult to detect, because there isn't any obvious coolant loss. You may find that there's still pressure in the cooling system, but it's just insufficient for what your engine needs. If you have examined the pump for leaks, checked the level of coolant and eliminated other problems, have your local mechanic inspect the impeller for signs of damage or wear.

If your car is overheating or your cooling system doesn't seem to be responding properly, you need to know the things to watch for. These are the two common reasons that a water pump will fail, which can cause overheating. With this information and the help of a reliable mechanic, you can keep your car on the road and avoid potentially damaging overheating problems. For more information, contact a professional like Steve's Radiator Service.