Servicing Your Cooling System

Your vehicle’s cooling system is extremely important because it’s what regulates the temperature in your engine and protects it from overheating, damage and breakdowns.

One of the most common causes of car problems and breakdowns is cooling system failure. A failure in the cooling system can cause severe engine damage. Problems can stem from low coolant levels, old coolant, or leaks. Fortunately, it’s easy to prevent problems by having your cooling system checked and maintenanced regularly. You should have your coolant flushed and refilled as often as your vehicle’s manufacturer recommends. Intervals typically range from 2 to 3 years, depending on the type of coolant and vehicle

Cooling System Operation
The main function of the Cooling System is to carry heat away from the engine and maintain the desired operating temperature. This is accomplished by circulating antifreeze/coolant through the engine, where heat is generated, and carrying it to the radiator to be cooled.

Modern automobiles operate in a wide variety of ambient temperatures, from well below freezing to well over 100 F. The fluid used to cool the engine must have a very low freezing point, a high boiling point, and it must have the ability to transfer heat. An adequate amount of an antifreeze/coolant and water mixture is necessary to reduce the possibility of engine overheating and freezing, and contain additives to prevent rust and corrosion in the cooling system.

Water is one of the most effective fluids for holding heat, but water freezes at too high a temperature to be used in automobile engines alone. The fluid used in most vehicles is a mixture of water and ethylene glycol, also known as “antifreeze” or “coolant”. By adding antifreeze to water, the boiling and freezing points are improved significantly.

The temperature of the coolant can sometimes reach 250 to 275 F (121 to 135 C). Even with antifreeze added, these temperatures would boil the coolant.  To prevent this, the cooling system is pressurized, which further raises the boiling point of the coolant. Most systems have around 14 to 15 pounds per square inch (psi), which raises the boiling point approximately 45 F so the coolant can endure the high temperatures produced in the engine.

Coolant Hoses – The radiator hoses and heater hoses are easily inspected by opening the hood and looking.  You want to be sure that the hoses have no cracking or splitting and that there is no bulging or swelling at the ends.  After the cooling system is refilled with the proper coolant mixture,  a pressure test should be performed to ensure that there are no leaks.

Belts – On most older vehicles, the water pump is driven by either a V belt or serpentine belt on the front of the engine that is also responsible for driving the alternator, power steering pump and air conditioner compressor.  These types of belts are easy to inspect and replace if they are worn.  Check for dry cracking on the inside surface of the belt. On newer vehicles, the water pump is often driven by the timing belt.  This belt usually has a specific life expectancy at which time it must be replaced to insure that it does not fail.  Since the timing belt is inside the engine and will require partial engine disassembly to inspect, it is very important to replace the timing belt at the scheduled interval.

If you think that your vehicle might need to have its coolant changed or system serviced, schedule an appointment at Escondido Auto Tech at (760) 745-4454 or online at