To keep a Mercury Cougar in top operating condition, routine maintenance is a necessity, including flushing of the radiator. Because gunk and grime can build up in a cars' cooling system, you should flush the radiator every other year. While this may seem like a complicated task, it's relatively simple and something you can do by following a few easy steps.
Park the Mercury Cougar on a level surface and engage the parking brake.
Open the hood and check the external temperature of the radiator. If it's warm to the touch, wait for it to cool off before you continue. Otherwise, proceed to Step 3.
Turn the radiator cap one full turn and step back. Even though the radiator is cool, it can still erupt and burn anyone nearby. After waiting 1 minute, remove the radiator cap completely.
Place a bucket with a capacity of at least two gallons underneath the Mercury Cougar's radiator and below its drain plug.
Remove the drain plug from the radiator and let the old coolant drain into the bucket. When complete, pour the old coolant into a sealable container for proper disposal.
Replace the drain plug and pour distilled water in the radiator until it's full. Next, open the drain plug and allow it to drain into the bucket. Keep repeating this procedure until the liquid coming from the bottom of the radiator runs free of debris. This step requires about 3 gallons of distilled water.
Insert the drain plug back into the original position and fill the radiator with fresh coolant. Be sure to monitor the plug, hoses and connections for any leakage.
Start the Mercury Cougar and turn the heater to the high setting. Let the car run like this for about 10 minutes and switch off the engine. Check the coolant level and add more, if necessary.
Put the radiator cap back on and close the hood of the Mercury Cougar.
