A vehicle's cooling system is designed to prevent it from overheating in the heat of summer and keep the engine cool in the winter without freezing. When functioning properly, you probably never give the cooling system a second thought. Most people only think about their cooling system when they pass a stranded motorist on the side of the road with his hood open and steam pouring out of the radiator cap. A few simple preventive maintenance steps will help you avoid just such a scenario.
Park the vehicle. Open the hood, apply the parking brake and allow the engine to cool down if it is hot.
Locate the coolant reservoir. This is usually a clear white plastic container next to the radiator. It will be marked on the side with a cold and a hot measurement line. If the measurement is below the full line, remove the reservoir cap and add a 50/50 mixture of antifreeze and water to bring it up to the full line.
Using an antifreeze tester, extract some liquid out of the reservoir and read the tester. It will show how much antifreeze is in the radiator. If your system is extremely low, add some straight antifreeze to the radiator. Run the engine to assure that it has been well distributed in the system. Let the engine cool and remeasure. If it is a little low, add more of the 50/50 mix until the system is full. If the liquid is a dirty brown color or is extremely low in antifreeze content when tested, you might benefit from a flush and fill of your cooling system (which should be done by a mechanic or auto expert).
Replace the cap and close the hood.
