Automobile engines work extra hard in the summer, and it is the cooling system’s job to protect the engine from overheating. In addition, additives in the coolant protect the radiator and internal engine components against wear and corrosion. Without proper cooling system maintenance, the odds of long term engine damage, and a summer time boil over, definitely increase.
Over time, engine coolant becomes contaminated and its protective additives are depleted. That’s why the system should be flushed and the coolant replaced periodically as recommended by the vehicle manufacturer. Older coolants used to require changing every two years or 24,000 miles, but most modern formulations are good for at least five years and 50,000 miles. See the owner’s manual or maintenance booklet to determine the service interval appropriate for your vehicle.