Keep Your Engine Cooling System Going Strong in Summer

This summer, play it cool behind the wheel.
by By Rich Ellis
Summer driving

Summer’s coming, and with it, warmer temperatures, vacations, and longer trips. We don’t want to be downers, but if your car’s cooling system isn’t up to par, things could go from fun-in-the-sun to stranded-in-the-sun too quickly for anyone’s liking. Because the truth is: cooling system failure is a leading cause of vehicle breakdowns.
 
Don’t let it come to that.  
 
The easiest way to make sure your summer plans stay on course is to pay attention to your vehicle’s cooling system now, while the weather’s still mild. Trust us, you’ll avoid a lot of aggravation, and possibly an unnecessarily expensive vehicle repair. 
 
Here’s how to maintain your cooling system. 
 

What the Cooling System Does

In the simplest of terms, the cooling system’s sole function in warm weather is to prevent the engine from overheating by removing heat from the engine. 
 
The combustion process generates a lot of heat. Coolant temperature can be well over 200 degrees and the engine block temperature near the exhaust manifold can be over 800 degrees. All that heat has to go somewhere, otherwise engine components are going to start failing. It’s the cooling system’s job to move that heat. 
 

How the Cooling System Works

Your cooling system works through heat transfer – it takes the heat from the engine and transfers it to the air. The liquid in your cooling system, also called antifreeze or coolant, is actually a 50/50 mixture of water and coolant. 
 
Pro tip: Why not just use water? Coolant has a higher boiling point than water and inhibits corrosion.
 
Coolant is circulated by the water pump through a series of passages in the engine. As the coolant passes by the engine, the engine heat is transferred to the coolant. The coolant leaves the engine through a rubber hose and goes to the radiator. As the coolant flows through the radiator, air passing over the radiator’s metal fins takes the heat from the coolant and passes it on to the surrounding environment. Air passes over the radiator continuously because the car is moving and because the fan is also moving air. The coolant, now cooled, returns to the engine via another rubber hose and the process begins again. 
 
While this can differ on certain vehicles, generally a belt or belts are responsible for driving the fan and water pump. The radiator cap maintains pressure on the cooling system and acts as a safety release valve should the pressure rise too high. 
 
The thermostat regulates engine temperature, either helping the engine warm up or cool off. Once the engine reaches operating temperature, the thermostat opens and allows the coolant to move to the radiator and the cooling process to begin.
 

Cooling System Maintenance Tips

Coolant
If the cooling system doesn’t receive regular maintenance, it’s not a question of whether it will fail, but rather when it will fail.
 
Here’s what you should be talking about with your technician when it comes to maintaining your cooling system.
 
Coolant – It needs to be changed regularly. Check your vehicle owner’s manual for the recommended replacement interval. If it isn’t replaced regularly, it loses its effectiveness to prevent corrosion in the cooling system – a problem explained below – and it also loses its freeze-protection abilities. The coolant level also needs to be checked periodically. If you run out of coolant, your engine will overheat. 
 
Radiator – It can corrode internally if coolant, with its corrosion inhibitors, isn’t used or changed regularly. When the radiator corrodes, it becomes plugged, preventing the effective circulation of coolant. Have the radiator and cooling system flushed periodically to remove any debris. Also have the radiator examined for any external obstructions, such as paper, leaves, bugs or other road debris that are stuck to it and blocking air flow, and for any signs of damage from stones and other projectiles that hit the radiator and caused leaks or bent fins.
 
Belts & Hoses – They’re rubber, which wears and degrades over time and with use. Replace them approximately every four years or based on your manufacturer’s recommendation. Have them examined for visible signs of impending failure, including cracks in the belt or soft or bulging spots in the hoses. If they fail, your cooling system stops working.
 
Water pump – On many vehicles, the water pump is driven by the timing belt. Since a timing belt needs to be changed at certain intervals, it makes sense to replace the water pump at the same time, and most technicians will recommend this. If your water pump fails, the engine can overheat. 
 
Radiator cap – Make sure it’s screwed on tightly. Look for any sign of leaks around it. Your technician can also pressure test the radiator cap to ensure it’s functioning properly when he or she performs a pressure test on the entire cooling system. And remember, never remove the radiator cap when the engine is hot. 
 
Also be on the lookout for signs of cooling system problems, like: 
The vehicle temperature gauge rising near the danger zone 
Coolant leaks, steam or hissing sounds under the hood
The distinct smell of coolant or an engine that’s running hot
 
Knowing and performing the maintenance your cooling system requires can prevent cooling system and engine failure.  
 
After all, it’s summer, and we’re all trying to stay cool. 
 

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