How to Perform an Automotive Radiator Flush
- 1). Park the car on a level surface and turn off the engine. Wait for the engine to cool if it is hot. Open the hood and examine the radiator and attached hoses for any breakage or leaks. If breakage is detected on any of the attached hoses, they need to be replaced.
- 2). Remove the top cap on the radiator, place a bucket or pan on the ground underneath the radiator and remove the bottom plug so the liquid in the radiator flows into the container. After the solution has emptied, place a water hose into the top opening and allow the water to run through the radiator until the water runs clear.
- 3). Place the hose into the bottom opening of the radiator and reverse flush the radiator until the water runs clear. Then go back to the top of the radiator and re-flush the radiator using the top opening until the water is clear.
- 4). Replace the plug in the bottom of the radiator. Put on gloves and fill the radiator reservoir with the appropriate coolant water mixture until it is visible through the top opening. Consult your vehicle owner's manual for the proper mixture ratio. Replace the cap on the top of radiator.
- 5). Start the vehicle and observe the hoses, plugs and radiator for leaks. If a small leak or trickle is visible, purchase a bottle of leak stoppage liquid product at an automotive store and add it to the radiator. This is only a temporary fix, however, and you should contact a mechanic. Any large leaks will require the immediate attention of a person knowledgeable in radiator repair.
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