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Put the Squeeze on Your Cooling System
Putting The Squeeze On Your Cooling System
Are your belts and hoses in good enough condition to last through summer?
By Peter D. du Pre
Overheating isn’t just a summertime problem. According to Wayne Manthei, manager of automotive replacement parts for Goodyear Tire and Rubber Co., overheating problems can happen year around, but summer is when most cooling system problems occur.
"Overheating caused by a faulty fan belt or a broken radiator hose can give motorists problems in the fall and winter, too, though summertime sees the most problems," said Manthei.
"Almost nine out of 10 radiator hose and fan belt failures create an emergency situation,” continued Manthei. “They frequently happen far enough away from home that they increase both the cost and inconvenience of repairs, as well as ruin a family vacation."
Drive belts, fan belts, and hoses are vital parts of your vehicle’s life systems. Belts deliver power from the vehicle's engine to such underhood accessories as the alternator, air conditioning compressor, radiator fan (on older vehicles), and other items. A broken drive belt can cause overheating and battery discharge and leave you stranded.
Hoses are just as important. They transport thousands of gallons of hot, pressurized coolant to and from the radiator every hour as well as serve as shock absorbers between the engine and the cooling system connections, preventing them from possible damage.
Underhood temperatures during hot summer weather can be as high as 280 degrees Fahrenheit. Heat from within and without the system breaks down coolant, hoses and belts, and put an additional strain on the water pump. As the system ages, the belts develop crack and fray, while the hoses deteriorate from both the inside and outside. Sludge starts to build up in the coolant, eventually clogging the internal passages of the radiator and engine. After awhile, any additional stress caused by low speed, high RPM driving, such as when towing a trailer or driving up to the mountains, can cause overheating.
To avoid these problems, Goodyear and Manthei suggest having the cooling system inspected before you get stranded. Take the vehicle to a qualified service center and have them inspect the entire heating and cooling system, not just the belts. They will test the coolant for acidity and its ability to withstand low temperatures without freezing, as well as test the pressure relief ability of the radiator cap, look at the integrity of the overflow tank, inspect the belts for wear, and check the hoses and hose clamps.
If you want to inspect your own cooling system, check the belts and hoses first. They are the number one cause of overheating problems. Just make sure the engine is turned off before you start. Look for cracks, bulges, splits, hardness, or sponginess on hoses. Squeeze them between your fingers. They should feel firm and pliant. Replace hoses that are mushy or overly soft.
Drive belts generally last longer than hoses, but they don't last forever. Most maintenance schedules suggest replacement of these vital underhood parts between 40,000 and 60,000 miles and finicky mechanics suggest replacement every two years or 40,000 miles. The two-year rule is important; many of the new composite drive belts don't exhibit any signs of fatigue until they fail. You won't be able to tell whether the belt is in good condition by looking at the part that faces out. Grab the belt with your fingers and twist it so the underside shows. Look for glazed sidewalls, cracks, fraying or missing chunks. Check for missing or cracking ribs on ribbed drive belts.
It is also a good idea to have the belt tension checked. Improper belt tension is a primary cause of belt failure. If the belt is too loose, it won't drive the alternator or water pump and will wear prematurely. A belt that is too tight tends to crack on the underside and puts additional strain on the alternator and water pump.
A properly adjusted fan belt should flex about 3/4 of an inch when pressed in between the pulleys with the thumb. Serpentine and ribbed drive belts may not flex this much. You’ll need a special gauge for this job, so have a mechanic do the check.
As for the coolant, have it changed every two years or 15,000 miles. Coolant, a mixture of ethylene glycol and water, breaks down with age, picks up contaminants that cause sludge, and becomes acidic. Have your mechanic check the condition of the coolant, radiator, and heater core. I don't advise doing this yourself because coolant is an environmentally hazardous substance. It pollutes the water table and is poisonous to people and animals. Your mechanic has special tools and procedures for changing coolant. In any case, when the coolant is replaced, have the mechanic back flush the system to remove scale, corrosion, and mineral deposits that build up over time and rob the system of efficiency.