I have a 1996 Subaru Legacy Outback Wagon. It has been overheating. I replaced the thermostat. I replaced the radiator cap. I drained the radiator, opened the bleeder and began to refill the radiator. Once it was full, I let the radiator "Burp" itself. I refilled approximately 1.5 gallons of coolant. This process took about 2 hours filling and letting the radiator burp itself. When it ceased burping, I put the radiator cap back on and closed the bleeder. At that point, I ran the car for about 15 minutes, of which for approximately 5 minutes I ran it at about 3000 RPM. The heater was blowing hot the entire time. Then I take it for a test drive. After about four minutes, the heater begins to blow cold and the temperature begins to rise until it hits near "red line". This usually occurs when I have slowed down or stopped at a light. I believe, but do not know, that there is still air in the system and that it is not full.
Am I filling the car properly? Am I correct that there is air in the system? What am I doing wrong?
Sometimes you just can't get all the air out of the system when you just try to burp it in the way you did. Try doing it this way.
Jack up the front of the car and put it on jack stands or you can also use ramps.
Once the front of the car is tilted up, run the engine with the radiator cap off and let it burp this way.
On some makes of cars the radiator cap is lower than the engine. Even though the engine has a bleeder installed it just won't get all the air out. Tilting the car up puts the engine on an angle so it forces the air to go to the radiator.
Try this method and let me know how you make out.