Every car has a cooling system. Some foreign cars, such as rear-engine VW’s, have an air-cooled system that is relatively trouble-free, but most American-made cars and many foreign cars have a combination liquid and air cooling system. Unfortunately, all the heat produced by an internal-combustion engine cannot be utilized as energy, and the excess heat above the normal operating temperature must be removed or else it will damage and even destroy the engine.
Overheating of the engine is a problem in all areas of the country, but especially in those sections where summer temperatures are high. Simple care and maintenance of your cooling system will help you avoid overheating problems.
The cooling system is basically simple. A conventional system consists of a radiator with cores through which water circulates to allow maximum air contact and heat removal; other components are a fan, a water pump that is belt-driven on the same shaft as the fan, a thermostat, hoses, coolant, and a pressure radiator cap. Most cars manufactured before 1972 have a conventional cooling system.
Some newer cars have a closed cooling system. In addition to the parts that comprise the conventional system, the closed system has a plastic see-through container and a hose that leads from the con¬tainer to the top of the radiator near the cap. As the liquid in the radiator becomes hot and expands, it overflows from the radiator into the reserve container. Conversely, as the radiator cools, the liquid is drawn back into it. A closed cooling system has a sign on the radiator cap that says “Do Not Open.” Follow these instructions; you should not open the radiator cap.
Keep the outside of the radiator clean. Remove bugs, leaves, and trash from the front of the radiator. Check the fan belts. If they are obviously quite worn or frazzled, go ahead and replace them. Do not wait until they break or you may be severely inconvenienced. When preparing for a long trip, lake spare belts with you and tools for replacing any broken belts.
- THE COOLANT
The coolant is an important part of the cooling system. Refer to your Owner’s Manual to find out what coolant is recommended for your car. The antifreeze-and-water mixture freezes at a lower temperature and boils at a higher temperature than water. Always use permanent type (cthylene glycol base) antifreeze. The colder the temperature the more antifreeze you will need. Even in mild climates, some of the newer cars require a mixture of antifreeze and water all the time.
The coolant level in your cooling system should be checked every two weeks or every 500 miles or before a long trip.
- ADDING WATER
The water you put in your radiator ideally should be free of alkali or other minerals. Since most service stations use tap water, you may want to be on the safe side and use rainwater or distilled water in the radiator. (Rainwater does not contain minerals, because it has not pnsseil through channels in the earth picking up these materials.)
- FLUSHING THE COOLING SYSTEM
Every two years your car’s cooling system should be drained, flushed out with clean water, and filled with new antifreeze. You can have this done at a service station or do it yourself.
- THE HOSES
The two primary hoses for your cooling system are extremely im-portant. One hose leads from the engine to the top of the radiator and the other leads from the engine to the bottom of the radiator. These hoses will rot with ordinary use. When they become soft and flabby (usually after about two years), it is time they were changed. Changing the hoses should coincide with flushing out the cooling system.
- OVERHEATING
When an engine overheats, the temperature indicator of diot light on the dashboard lights up. Stop immediately! With luck, the engine has not yet been damaged but continued driving surely will damage it. Open the hood and look for a broken fan belt. If the fan belt and fan are in good condition, the coolant may be low. Do not open the radiator cap of a hot engine. Use a hose to spray water on the radiator to cool it before opening the radiator cap. If the coolant is low, crank the engine and let it idle while adding coolant. Never add cold liquid to the radiator of a hot engine that is not running. Doing this may damage the engine.
If the fan belt is neither loose nor broken, and the liquid coolant level is correct, then the next most likely problem is the thermostat.
A thermostat is a small round device, about two inches in diameter- or slightly larger than a silver dollar-which is mounted under a metal bnicket where the top radiator hose attaches to the engine. When the engine is started cold the thermostat is closed; the water pump sends coolant to the engine block to be heated, mul as the engine comes rapidly up to proper operating temperature (about 190° F.), the thermostat opens.
This allows the heated liquid from the engine to circulate through the radiator, where it is cooled. The movement of the car and the rotating fan cause cool air to pass through the openings in the radiator, cooling the liquid, which then flows to Ihe engine block and other engine parts picking up heat again. In this circulating process the thermostat helps to maintain the proper engine temperature by opening and closing. Proper engine temperature results in better gas mileage, better acceleration, and less engine wear.
If the engine still overheats, the trouble may be that the radiator core is full of rust and corrosion and must be boiled in a cleaning Noluiion or rodded out. This is a job for the professional radiator shop. Another possible, though remote, problem is a defective fan clutch, in which case the pulley turns but the fan does not.
QUESTION: Is the cooling system designed to keep the engine as cool as possible? No, it keeps the engine at the proper operating tempera-tine. Always remember that overheating of the engine leads to untold I roubles, all of which can result in expensive repair bills. Obviously, you should make every effort to see that your engine does not overheat.
- PRESSURE RADIATOR CAPS
Modern cooling systems are under pressure and use pressure type nuliiiloi caps. Your coolant will be lost if the cap leaks. The radiator flip is designed so that it has a pressure-relief valve. After the pressure In I he radiator reaches a certain point, the pressure-relief valve is aclunlcil, and some of the pressure is released. When you check the looliini level in a conventional system, make sure you replace the cap tightly.
- WATER PUMP AND FAN
The water pump should last a long time, but eventually it will wear out and need replacement. Leaks and/or squeaky noises are symptoms Ihiil the water pump is approaching the time of trouble. The only thing you can do to prolong the life of your water pump is to keep antifreeze or a rust preventive solution in the cooling system at all times.
If you have an older car that does not require year-round antifreeze, you may decide to flush the cooling system in the spring and put water alone in the radiator. In this case be certain to add a can of rust preventative, which will lubricate the water pump as well as help prevent rust. Antifreeze also helps prevent rust and lubricates the water pump, so if you leave antifreeze in your cooling system year round, you do not have to add rust preventative.
The engines of some modern cars, such as the Chevrolet Vega and Ford Courier, have aluminum blocks. The proper concentration of the antifreeze recommended by the manufacturer is especially important in aluminum-block engines to prevent corrosion.
The fan normally lasts a long time and seldom gives trouble. The fan belt may break, but you can have a mechanic replace the belt or you can do it yourself