We are always asked if it's really necessary to perform a coolant flush. So I want to educate you on exactly what the cooling system does. Engine coolant, some may know it a antifreeze, runs through your engine's cooling system. The water pump moves the fluid from the radiator to the engine and back again. The primary job of the coolant is to transfer excess heat from the engine to the radiator. The radiator's job is to allow cooler air to bring down the temperature of the coolant. Pure water is the best fluid for transferring heat, however at 190 degrees Fahrenheit, water is extremely corrosive to the inside of your engine. For this reason it's mixed 50/50 with antifreeze, or coolant which contains anti-corrosion additives. If coolant is not mixed with water, your engine can run hotter than normal. Coolant also has anti-cavitation additives to prevent cavitation around the water pump impeller.
The interesting thing about these chemical additives is that they wear out over time, much the way prescription drugs lose their potency and effectiveness over time, hence the discard date on pill containers. We want to flush coolant before the anti-corrosion additives lose their effectiveness.
Another consideration is that the current the engine starter uses returns to the battery negative terminal by running from the starter through the block to where the big black cable is attached, and then back to the battery negative terminal. This process can build up a slight charge in the engine coolant over a long period of time, resulting in a condition called electrolysis. Electrolysis will cause metal to come off the inside of your engine and be deposited in the radiator and heater core, which explains why we sometimes find that a failed radiator we take out is significantly heavier than the new one we install. The same holds true for heater cores, which can be very difficult to access and replace.
So the answer to the coolant flush questions is a definite YES. We want to flush out the coolant and replace it with new before it is visibly bad, due to additive depletion and the possibility of electrolysis. The usual time frame is two years or 30,000 miles for standard coolant, however some cars have extended life coolant that can go longer. The bottom line is that flushing and keeping the coolant fresh is always less expensive than repairing a heater core or radiator, head gasket or engine rebuild/replacement.
Don't wait until it's too late, flush your vehicle's cooling system today. Give The Auto Analyst, your one stop auto repair shop, a call today at (530) 621-4591 or visit our website at www.theautoanalyst.com to schedule an appointment.