How much to you know about your vehicle radiator and what it does to keep you cool? First of all, your radiator is located at the front of the engine right behind the grill. The radiator is a type of heat exchanger designed to transfer heat from the hot coolant that flows through it to the air blown through it by the fan. Most modern cars use aluminum radiators. The coolant flows from the inlet to the outlet through many tubes mounted in a parallel arrangement that make up the body of the radiator.
Since the engine works harder than most of the other auto parts, it has a tendency to overheat; therefore, it needs a cooling system that would keep it operating at the right temperature. Even under normal conditions the engine produces an enormous amount of heat. The work of the cooling system is to remove at least one-third of that heat in the combustion chamber so the engine won't overheat. The radiator is the device in the cooling system that dispels the heat absorbed by the anti-freeze or coolant mixture from the engine. It has tubes that hold a large amount of water-coolant mixture and passages that provide large areas in contact with the air outside the vehicle. Water is mixed with the coolant and is circulated around the engine through the cylinder block and head. In the process the water/coolant absorbs the heat from the engine and its parts. The water/coolant is then pumped from the engine towards the receiving tank at the top of the radiator. It spreads over the tops of the tubes and passes through them, thereby, losing its heat to the air which passes around outside the tubes. After getting cool in the radiator, the water/coolant goes back to the engine to absorb heat again and the cooling process continues as long as the engine is running. Without some way to cool off, your engine would turn into a block of useless metal in no time at all.
Most people know the green stuff in the radiator keeps the engine from turning into a block of ice in the winter, but it also helps keep things cool in the summer. Radiator coolant actually raises the boiling point of the water, allowing it to carry more heat away from the engine and that means a cooler running engine. If you are running low on coolant, things can get steamy hot fast. It only takes a second to check your coolant level. Most cars have an opaque coolant overflow tank right next to the radiator. There are markings on the side indicating low and high levels of coolant. Always check your coolant level when the car is cold. If the level is low, it's time to top it off. The engine takes a 50/50 mix of coolant and water. You can measure and mix it yourself or you can buy the premixed coolant that is simply ready to pour.
According to the U.S. Department of Transportation, cooling system failure is the leading cause of mechanical breakdowns on the highway. Coolant neglect is one of the leading causes of cooling system breakdowns. Most vehicles will lose a little coolant over time due to evaporation from the reservoir. But a significant loss of coolant in a relatively short period of time usually signals a leak, a radiator cap that isn't holding pressure, or a cooling system that is running too hot. It's a good idea to visually inspect the radiator, water pump, hoses, and freeze plugs as well as the rest of the cooling system for external leaks. Hoses that have white streaks on them may be indicating leaks. If no leaks are found, the loss of coolant may be due to long term neglect or a temporary episode of overheating.
Checking the strength of the coolant to determine the concentration of antifreeze in the coolant is just as important for hot weather driving as it is for cold weather. A 50/50 mixture of antifreeze and water will provide boiling protection up to about 255 degrees and freezing protection down to -34 degrees. Increasing the concentration of antifreeze in the coolant will raise its boiling temperature and lower its freezing point. The maximum concentration however, should be limited to 65% to 70% because too much antifreeze and not enough water reduces the coolants ability to carry heat - which increases the risk of overheating in hot weather.
Something else to keep in mind is that there are two main antifreezes available, EG (ethylene glycol) and PG (propylene glycol). These have slightly different specific gravities or densities, it is important to be sure the correct type is being used. The main difference between these two is the additive packages. To reduce confusion, several antifreeze suppliers like Peak and Prestone are now selling a universal type of antifreeze that is compatible with all types of antifreeze and all makes and models of vehicles. Some argue this is not entirely true, but the universal type seems to work okay and is widely accepted in the aftermarket. It is important however, to not mix types of antifreeze. If you are adding or changing coolant, it is best to follow the recommendations found in the owner's manual and use the same type of coolant that was in the system.
While coolant is usually the culprit in many radiator problems, there are other things that can go wrong or can plug up the whole works. Radiator problems often start slowly due to clogging from rust and debris. This reduces the radiator's ability to transfer heat and it reduces the effectiveness of the cooling system too. A clean radiator is a cool running radiator. For maintenance, your radiator requires a flush, usually once a year. This flush will clean out the rust and other debris that could create a problem. Remember, dealing with your radiator when your car is running or still warm from running is dangerous due to very hot liquid. Allow your car to cool completely before removing the cap or otherwise touching the radiator.
As with any vehicle maintenance, your radiator maintenance should be up to date and done on schedule. Forgetting or letting it slide till next year might cause you far more headache and cost than simply doing it on time. It's much easier to do the maintenance than to replace the entire radiator or engine of your vehicle. You don't want to be left sitting on the side of the road while your engine takes a steam bath.
