Steps on Flushing the Coolant in a 1999 Ford Econoline
- 1). Drain the cooling system. You must first remove the radiator cap, which is located on top of the radiator. Engine must be cool before opening. Place catch basin under the radiator drain valve and open the lower radiator drain valve. This valve is located on the bottom of the radiator and looks like a wing nut. Allow the system to drain into the catch basin. Once drainage is complete, close the lower valve.
- 2). Fill the radiator. The radiator is filled with a mixture of clean water and coolant system flush. The mix ratio must be the one recommended by the coolant flush manufacturer. Do not replace the radiator cap.
- 3). Circulate the mixture in the radiator. Start engine and run at idle. As the engine heats up, the mixture in the radiator will circulate. You will be able to see this through the open radiator cap. Allow to circulate for five minutes and then turn off the vehicle.
- 4). Drain the coolant system flush from the radiator system. Allow the radiator to cool before attempting this. Place the catch basin under the lower radiator valve and open the valve. Allow the radiator to drain completely, then close the valve.
- 5). Fill the radiator with clean water. Start and run the vehicle at idle until you see the water in the radiator moving. Allow to circulate for five minutes and shut off the vehicle.
- 6). Drain water from the radiator. Allow system to cool and then open lower radiator valve and drain completely into the catch basin. Close the lower radiator valve.
- 7). Fill radiator with a mixture of fresh coolant and water per manufacturer's instructions. This is normally a 50 percent ratio. Start engine and allow to run at idle for around five minutes. The level in the radiator will usually drop. Add more coolant and water until full. Shut off engine. Wait for another five to 10 minutes to see if the level starts to drop again. If so, add coolant mixture to top off and replace radiator cap.
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