Surviving the Summer

By Dave Hamby 

 As this summer wears on and the heat gets more oppressive, we’ll see more and more cars broken down on our daily commute. While some of these break-downs are inevitable, others can be avoided with just a little preventative maintenance and a little forethought.

 It’s obvious from the green stain spreading out from under these disabled machines that the major cause of many of these breakdowns is a failure of the cooling system. While many motorists will take the preventive maintenance necessary to prevent a freeze up when winter comes, few consider it necessary to perform any maintenance for summer. The fact is, it seldom gets cold enough in this part of Texas to really worry about freezing, but it’s often hot enough to strain the abilities of your cooling system.

 Antifreeze is designed to perform several tasks. The first task is self explanatory in its name; it’s supposed to keep the coolant in your engine from freezing and the resulting pressure from the formation of ice from cracking your engine block or cylinder head.

 Its second major task is to transfer heat from the combustion chamber of the engine to the radiator. Internal combustion engines have poor thermal efficiency, and as a result a great deal of the energy released in the combustion of the fuel is just plain, good old fashioned heat. Without the cooling system this heat would exceed the melting point of the metal that your engine is made of, and it would soon become one solid lump.

 While modern engines are much more efficient, some of this efficiency comes at the expense of a higher operating temperature. This means that you have less cushion between normal operating temperature ranges and meltdown. It also means it’s more important than ever that your cooling system is working at peak efficiency.

 Antifreeze’s third major task is to prevent corrosion in your cooling system. This is where the system maintenance is most important. Corrosion is a major factor in many cooling system failures.

 The last function antifreeze needs to perform is lubrication of the cooling system or water pump.

Space limitations prevent me from going into great depth and detail of how and why your cooling system works. One thing I will expand on is the corrosion facet of a cooling system. Anyone that has ever seen a nail that has been left outside in the elements knows that when metal gets wet, it oxidizes. Ferrous metals like steel and iron get rusty, aluminum and other metals get pitted and have different color oxides form on them. Engines are made of ferrous metals and aluminum.

 The heat generated from the combustion process means that corrosion prevention methods like paint and primer cannot be applied to the cooling passages. Size limitations and cost restrictions prevent manufacturers from using ceramics and other coatings to do this task.

 Antifreeze is your engine’s only protection from internal corrosion.

 As antifreeze ages it becomes acidic, and as it becomes acidic it goes from something that prevents corrosion to something that creates corrosion. This corrosion will eat away at your radiator, your hoses, and your freeze plugs. It will also eat away at the engine block and cylinder heads, and the by-product, rust, will clog cooling system passages. As these passages become restricted less coolant flows through them, and as a result there is less heat transfer. As heat transfer diminishes, the engine’s operating temperature gets higher. All of the effects of corrosion are detrimental to your cooling system's ability to cool your engine.

 So now that you know more than you ever wanted to know about your cooling system, what can you do to prevent breakdowns? A cooling system check and radiator flush is the best insurance you can take out. You can have this done by a mechanic or you can do it yourself.

 If you do this yourself, be certain you check all of the hoses for cracking and swelling. Replace any that are suspect. Check the clamps and make certain they’re tight and not about to fail. Look for any leaks and check the fan belts to make certain they’re in good working order.

 Remember that when you’re disposing of your old coolant to use some caution and good sense. While antifreeze is not considered a hazardous material, it is very toxic to humans and animals. The radiator flushes often are hazardous materials. Read the instructions carefully and take the proper precautions.

 Many newer cars now have electric fans. Check the fans and make certain they’re working as they should. While doing this check on my own car, I discovered that both of my cooling fans have failed and need repair. I never had any symptoms of overheating …yet. It’s very possible that had I not made this check, I could be buying a new motor before the summer is over.

 Make certain the antifreeze you use is the correct one for your car. These new Dex-cool antifreezes may be good for 50,000 miles, but if you put them in a system that’s not designed for them you can experience an expensive cooling system failure in a very short time. Under no circumstance should this type of antifreeze be used in a system that has a lead-copper radiator. Do not mix different types of antifreeze. If there’s the remotest possibility of a cooling system leak and you have pets you love, you might consider buying a new non-toxic antifreeze.

 As long as you’re preventing an automotive disaster, there are a couple of other things you may want to check. Have you changed your oil recently? If not, it’s a good idea to do so before the summer doldrums set in. High operating temperatures have an adverse affect on how well an oil can lubricate your engine. You might consider going to a heavier viscosity oil like from a 10w-40 to a 20w-50 or even going to a synthetic or a synthetic blend oil.

 Check your air filter. Hot air is not as dense as cold air and a clogged air filter will have much more of an adverse effect in hot weather.

 Check your tires for uneven wear, proper inflation, and broken belts. Higher road temperatures will contribute to tire failures.

 Check out your a/c system and make certain it’s not on the brink of failure. If you wait until August when it’s the hottest and have it fail then, you may find you have to wait several weeks before a technician can get around to repairing it. This can be real bad for your work environment as well as your social life.

 If you don’t know how to check these out for yourself, ask your mechanic to check them out for you. I’ve always found it interesting that folks will have this stuff checked out on a used car they’re thinking of buying, but won’t do it for a used car they’ve owned for a number of years.

 Remember that an automobile is just a machine and that Ben Franklin’s saying, "An ounce of prevention is worth a pound of cure," is just as true for it as it is for everything else. If you’re like most folks and really depend on your car, then this advice is more important than ever.