If you go to put coolant in your car and find that there’s gunk floating in your fluids or if you turn on the heat and only cold air comes out, your radiator might need flushed. If you want to try it at home, follow these steps on how to flush a radiator.
Before you start working, make sure your engine is completely cooled down. Don’t try to flush the radiator unless your car has been sitting for at least two hours.
Once the car is cooled off, jack up the front so it’s easier to do work underneath. Then you’ll pop the hood and look for the radiator, located near the engine. If you can, use soapy water to clean off any grime on the radiator, and then check for damage like rust or leaks.
After that, put a drain pan under the radiator’s drainage valve under the car, unscrew the bolt, and let the coolant drain out, then replace the plug. Back under the hood, use a hose to flush the radiator with water and turn the car on for ten minutes. Turn it off, let it cool, drain the water, add new coolant, and you’re done!