A car’s radiator and cooling system should be cleaned regularly to keep them functioning properly. Over time, solid deposits can build in a car’s radiator, which can clog the cooling system. Flushing these clogs from the radiator helps keep a car’s cooling system in shape.
- Wrench or phillips head screwdriver
- Rag or cloth
- Radiator flush solution
- Receptacle (for used coolant)
Steps to Flush a Radiator
- Locate the radiator’s drain plug, which can be found anywhere along the bottom of the radiator. The plug may appear as a screw plug, a bolt plug, or a petcock drain valve.
- Place the coolant catcher beneath the drain. Unscrew the plug and drain the coolant until the receptacle is completely empty.
- Replace the plug after emptying the coolant.
- Remove the radiator cap.
- Pour all of the radiator flush solution into the radiator. Fill it to the brim with water.
- Replace and tighten the radiator cap.
- Start the car. Let the engine run until it gets to its operating temperature.
- Turn the heater on. Move its temperature control to the hottest position. Leave the car running for 10 minutes with the heater on.
- Turn the engine off and wait for it to cool down. Do not open the radiator cap if it is still too hot to touch.
- Open the radiator once the engine has cooled down. Drain the entire contents of the radiator into the coolant receptacle.
- Refill the radiator with fresh coolant. Fill it with a 50/50 mixture of water and coolant.
- Replace the radiator drain plug or fully close the petcock valve.