How to flush the coolant system
 

Find the radiator cap located near the front of your vehicle's engine and loosen the radiator plug (it resembles a wing nut) found on the radiator's backside. This allows the coolant to drain. Place a pan underneath to catch the liquid.

Remove the radiator cap and thermostat. Turn your engine on and place a garden hose into your coolant line. Create a slow, continuous flow of water into your engine while coolant runs out from underneath.

Check that your temperature gauge doesn't go too high. Running the heat on high opens the heater core and gets the coolant flowing.

Shut off your engine and the hose when the coolant is just about clear. Allow the remaining coolant (or water) to run off the bottom of the radiator plug before blowing compressed air through the line to clear any water from the line.

Tighten the radiator plug and repeat Steps 1 through 6 to flush the overflow reservoir.

Consult your vehicle owner's manual for the proper amount of coolant for your engine's cooling system. Add the coolant through the radiator cap and fill your overflow reservoir.

Start your engine and check that the temperature gauge doesn't register too high. Dispose of the coolant properly.