How to Flush the Radiator in a Nissan Sentra
- 1). Move the Nissan Sentra to a flat area and engage the parking brake. Then, open the hood and touch the radiator. If the radiator is warm, wait until it is cool before you continue. Opening a warm radiator is dangerous, because it can spew burning hot coolant on anyone near it.
- 2). Remove the radiator cap by turning it one full turn, step back and wait a few seconds, and then completely remove the radiator. The pause allows the internal pressure to disperse to ensure the radiator doesn't erupt.
- 3). Place a bucket with at least a 2-gallon capacity underneath the radiator and below the drain plug. The plug is usually on the passenger side bottom of the radiator in most Nissan Sentras.
- 4). Loosen the drain plug to allow the coolant to drain into the bucket. Be careful when loosening the plug because it's plastic and somewhat fragile in most Nissan Sentras. When the coolant finishes draining, pour it into a sealable container for proper disposal later.
- 5). Shut the drain plug and fill the radiator with distilled water. Then, open the radiator plug and let the distilled water flow into the bucket. Repeat this procedure until the water that drains from the radiator is free of debris. You need to pour about 3 gallons into the radiator to flush completely.
- 6). Make sure to tighten the drain plug back to the closed position and fill the radiator with fresh coolant to within an inch of overflowing. You will need approximately two gallons of coolant to fill the radiator of a Nissan Sentra.
- 7). Start the Nissan Sentra and turn the heater on high. Allow the car to run like this for about 10 minutes. Switch the engine off and check the coolant level. Add more coolant if the level retreated. Then, put the radiator cap back on and close the hood.
Source...