How Do You Bleed a Cooling System?

To bleed a cooling system, release the drain plug from underneath the radiator, and flush the system with a radiator flush solution and water. Refill the radiator and reservoir tank with 50/50 pre-diluted coolant.

  1. Position the bucket

    Locate the drain plug for the radiator, and position the bucket underneath it.

  2. Drain the coolant

    Use a screwdriver or a hex-bit tool to remove the drain plug, and allow the coolant to drain into the bucket. Replace the plug.

  3. Set up the radiator flush

    Remove the radiator cap, and fill the radiator with radiator flush. Insert a garden hose into the radiator. Set the water to a gentle flow, and allow the water to fill the radiator to the top.

  4. Warm up the car

    Turn on the engine, and let it run until it reaches normal operating temperature. Turn the heater on high, and allow it to run for 10 minutes. Turn off the engine.

  5. Drain the radiator

    Remove the drain plug, and drain the flush solution. Start the engine, and run water through the radiator until the water comes out clean. Return the plug to the drain.

  6. Refill the radiator and reservoir tank

    Fill the radiator with fresh coolant, and top off the reservoir tank.