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Benefits of Having a Coolant Flush

Maintenance is always a better choice than unwanted repairs when it comes to vehicle engines. Most of us know this, and most of us do it by making sure our cars receive regular oil changes and tune-ups. Coolant flushes are another important part of maintaining your engine, and need to be performed on a regular schedule.

It’s important to understand that coolant is essential to a car engine because it helps prevent engine overheating. As it flows through the engine, the coolant pulls heat and picks up some dirt, sludge and rust. After time, it begins to lose its effectiveness. Regular coolant flushes will keep your cooling system clean and in good shape, and your engine, too. Let’s take a look at what happens during a coolant flush service.

Examine the Radiator

Your technician will first examine the radiator for signs of corrosion or rust. The technician will also inspect any wear that may require replacement, then, check the hoses and pipes for any leaks. Next, the technician will remove the radiator cap and check the attached coil for signs of wear or sludge buildup. Tension on the radiator cap coil when it is in place is what maintains the correct inside pressure, so this is an important step.

Drain the Radiator

Draining the radiator is the next step. A technician will open the drain plug near the bottom of the radiator. To flush the radiator, the technician will first replace the plug, then fill it with water. Next, the technician will start the car and let it run for 10 minutes to help the water cycle through. This procedure will be repeated two or three more times to ensure the system is fully flushed of old coolant.

Add New Coolant

Coolant is actually a mixture of antifreeze and water. Your technician will use the mixed coolant to fill the radiator until the fluid is visible. Next, the technician will bleed the complete cooling system of any air pockets by removing the cap, starting the car and letting it run about 15 minutes with the heater on. This allows the coolant to run through the system and removes any air pockets.

How Often Should I Have the Coolant Flushed?

Now that you know what happens during a coolant flush service, you should make it a regular maintenance task. Check your owner’s manual or follow these general guidelines for a recommended service interval.

  • Normal driving conditions: 50,000-100,000 miles
  • Severe driving conditions: 30,000-50,000 miles

Draining and refilling the radiator is not the same as a flush. It removes some of the dirty fluid, but not all. Only a complete coolant flush can do that.