The cooling system keeps our engine from overheating. Its job is to move heat away from the engine. Let’s talk about the various components of the system and how they work to accomplish this.

The radiator is the part most everyone associates with the cooling system. Coolant flows through the radiator which has fine cooling fins that draw the heat out of the coolant and dissipate it into the air. To make sure there’s enough airflow over the radiator, a fan pulls air over the cooling fins even when the car is idling.

In some vehicles, the fan is powered by the serpentine belt. On others, an electric motor runs the fan. Electric fans turn on and off as needed. You may have heard the fan kick on shortly after you turn your car off. The sensor has determined that the engine needs a little help cooling down to a safe temperature.

A hose connects the radiator to the water pump. The water pump pushes the water into the engine block. Now the engine block and cylinder heads have passages for the coolant to pass through without getting into the oil or the combustion chamber. These passages are referred to as the “water jacket”.

While the coolant is passing through the water jacket, it absorbs heat from the engine on its way to the radiator for cooling. Between the engine and the radiator is a gatekeeper called the thermostat. The thermostat’s job is to regulate the temperature of the engine just like your home thermostat regulates the temperature of your house. It gets your engine up to the correct operating temperature and then keeps it from overheating.

When your first start the engine, it’s very cold and needs to warm up. So the thermostat blocks the flow of coolant to the radiator. As the engine warms up, the thermostat starts to let coolant flow through the system.

The final component I want to talk about is the overflow reservoir. This bottle is designed to hold some of the coolant. It’ll have a mark that indicates whether or not you have enough coolant. This is where you should add coolant if you just need to top it off.

Caution: never open the reservoir or the radiator cap when the car’s hot. The cooling system is pressurized and opening them while it’s hot can cause hot coolant and steam to escape resulting in serious burns.

Cooling system failure is the most common mechanical failure in vehicles. Your service center can do a periodic inspection of the components for leaks, loose connections and weakening hoses.

Your manufacturer has also specified a cooling system service interval. With a cooling system service, the old coolant is replaced with correct clean fluid that contains the additives required to prevent corrosion. The additives are depleted over time and you need fresh fluid for adequate protection. Your radiator pressure cap should be replaced at this service as well.

The coolant system is a vital part of your vehicle. It is also the second most common cause for vehicle failures. Even though coolant system failure is fairly common, it is easy to prevent.

The most recognizable part of the coolant system is the radiator.  It is connected to the engine with hoses and is filled with coolant.  The coolant draws heat off the engine and then goes into the radiator.  Air passes through cooling fins to reduce the temperature of the coolant and then it’s back to the engine again.

There are several ways for the cooling system to fail.  Most common is with the coolant itself.  Coolant is a mixture of water and antifreeze.  The proper mixture keeps the coolant from either boiling away or freezing. Both of which can result in massive engine damage.

Another very important coolant issue that is often overlooked is the age of the coolant itself.  Antifreeze has additives that protect the coolant system from corrosion.  As these additives are depleted over time, they can’t protect the radiator and other parts from rust, scaling and corrosion.  Old coolant may still keep your engine cool, but it won’t protect it from corrosion.

If you see a warning message to check the coolant or if the temperature gauge is in the hot zone your cooling system needs to be checked.  It’s OK to add water or antifreeze yourself. But you need to be cautious. Remember four things.

• First, you never want to open the radiator pressure cap. You could be severely burned.
• Second, try to get to your service center immediately if your coolant is low. If that is not possible, follow the directions in your owners manual – it will direct you to only make additions to the coolant overflow bottle.
• Third, remember that you need a proper mixture of water and antifreeze. If you make an emergency addition to your cooling system, follow-up with your service center where they can make necessary corrections.
• Fourth, not all cars use the same type of antifreeze. You need to check your owners manual to make sure you use the right kind. Mixing antifreeze types or using the wrong kind of antifreeze may void the manufacturers warranty on your cooling system. Again, another reason to rely on your service center to do things right.

Remember, your local service center has the equipment to change your coolant quickly and inexpensively.

You may know that most automotive failures are tire related, but do you know the second most common cause for vehicle failure? Nope, it’s not teenagers. It is the coolant system.  But, if you take good care of your coolant system, it will take good care of you.

A car’s engine creates a lot of heat – so much heat, that if it is not properly cooled, the engine can lock up, resulting in massive damage and repair bills. But when everything is working right, your engine operates at the proper temperature and all is well. Without antifreeze in your cooling system, the water could freeze and cause engine damage.  This could be very expensive, not to mention inconvenient.

The right mix of water and antifreeze protects the engine against damage from freezing and overheating.  Antifreeze also protects the coolant system against corrosion that could cause the system to fail. The thing to remember is this: coolant system failure is very common, but it is also very easy to prevent.  Your service center knows the manufacturers’ recommendations, and can tell you when the coolant needs to be changed.  They can also perform a coolant system service.

Even the best antifreeze cannot completely protect the coolant system from harmful deposits forever.  The anti-corrosion additives are used up over time, so the coolant must be replaced.  A coolant service cleans out the system and replaces the old fluid with fresh coolant. A coolant system service is a low-cost way to protect against major engine repairs down the road. Prevention is the key.  Be sure to watch out for the two main warning signs: if your temperature gauge is in the “hot” zone or if you get a message warning you to check your coolant.  If you take a look under the hood, you will see the coolant overflow bottle.  You can see there are lines that indicate the proper level of coolant … if your engine is cold – or if it is hot.

You can add water or antifreeze to that bottle yourself, but be careful.  First, you never want to open the radiator pressure cap.  The steam could severely burn you.  Second, try to get to your service center immediately if your coolant is low.  If that is not possible, follow the directions in your owner’s manual.  Third, remember that you need a proper mixture of water and antifreeze, or you will damage your engine.  If you make an emergency addition to your cooling system, follow-up with your service center where they can make necessary corrections.  Fourth, not all cars use the same type of antifreeze.  You will need to check your owner’s manual to make sure you use the right kind. Mixing antifreeze types or using the wrong kind of antifreeze may void the manufacturers warranty on your cooling system.  If you’re not sure, ask your service technician for guidance.