2003 Tbird - Air in cooling system

Does anyone have a trick to get the air out of the cooling system? I’ve burped it 5 times. Every time it will run at normal temp then all of a sudden start overheating. As soon as I turn the heat on it drops back to normal. This is the second time I’ve replaced the heater control valve and both times I’ve had the same problem with air pockets. It’s also a new tstat and recently been flushed.
 
How many miles is on the car? No leaks showing?? If you continue to get vapor in the system after following the proper burping procedure in the manual, you could have some type of a internal leak of the cooling system. A head gasket leak or cranked block are possibilities. The radiator can be checked for the presence of carbon dioxide, CO2, from the combustion in cylinders with a test kit like in the links below. Can be gotten at NAPA or other auto parts stores too.


 
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Does anyone have a trick to get the air out of the cooling system? I’ve burped it 5 times. Every time it will run at normal temp then all of a sudden start overheating. As soon as I turn the heat on it drops back to normal. This is the second time I’ve replaced the heater control valve and both times I’ve had the same problem with air pockets. It’s also a new tstat and recently been flushed.

I read a thread a while back, I think there is a bleeder valve under the hood on the drivers side up close to the windshield.
 
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It’s got 110k. There are no leaks that I have found. The car runs perfect and I don’t believe there is a head gasket leak or cracked block. I’ll look into those kits. Thanks
 
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Hi everyone,

I'm working on a 2003 Thunderbird for a friend. 69,000 miles. It had set some kind of code that someone else mentioned to her that left her thinking it needed a thermostat. That is third-hand info so I have no idea what that code was, the car had none set when I got it. I drove it from her house to mine (about 8 miles) with no problems.

I replaced both hoses, the belt, and the thermostat and housing all just as preventative maintenance. I followed the bleeding procedure as outlined in the video given above. I've bled it 3 times now and each time I'm still getting air, but less each time.

It will sit and idle at normal temperature. I let it idle for 20 minutes this morning after bleeding it. Took it for a test drive and within a mile the temp started rising, as it did each other time I bled it. I came right back and it has not overheated, but it seems like it would if I kept driving it.

My question is, when bleeding it, is it important to let it cool completely down, like overnight so that it's cold as possible? Or can I bleed it again after it's cool enough to remove the cap? It seems like it purges more air after it sits overnight. It's still warm to the touch and it hasn't burped enough air into the fill tank to let me put any coolant in. Each time it's sat overnight I've had to top that off, it was below the lowest fill line each time.

I can keep it as long as I need to but it's stressing me out. I've never seen a cooling system this finicky. Any input will be greatly appreciated. Talk me down!
 
When you filed the coolant bottle did you remove the cap over the thermostat housing to let the air out. Then continue filling the coolant bottle and then start the engine and open the heater BLEEDER screw just next to the coolant bottle?
Sort of... I started (from empty radiator after replacing hoses) the filling process at the cap over the thermostat. Once the air settled out of that, I closed it and filled the rest at the bottle. Then started the engine with the bleeder open. Then let it get warm, put the cap on, and waited for coolant to run out of the bleeder.

The first 2 times I did that, I removed the thermostat cap to find a little air in it there. Filled there again. The 3rd time, there was no air in the thermostat housing so I haven't removed that cap again. Otherwise I've followed the procedure above.
 
Each time I've bled it, I've gotten a little more air out (progressively less each time but a little each time) but honestly the amount of air I'm getting out each time now doesn't seem like it would be enough make it run hot. I'm not familiar with these engines though.
 
  1. Remove the engine fill cap.

  1. Open the heater air bleed.

  1. Add coolant to the degas bottle allowing the system to equalize until no more coolant can be added.
  1. Install the degas bottle cap.




CAUTION
CAUTION: Care must be taken to make sure the accessory drive belt does not become contaminated with engine coolant.




  1. Add as much coolant as possible to the engine fill. The heater air bleed will remain open.
  1. Install the engine fill cap.
    • Install the engine fill cap until contact is made and then tighten an additional 45 degrees (1/8 turn).


  1. NOTE
    NOTE: The heater air bleed remains open.

    Start the engine and turn the heater to the defrost (90°F) position.
  1. Close the heater air bleed when a steady stream of coolant escapes during engine idle.

  1. Allow the engine to idle for five minutes, add coolant to the degas bottle as needed to maintain the cold fill MAX mark.
  1. Reopen the heater air bleed to release any trapped air and close again.

  1. Maintain engine speed of 2,000 rpm for 3-5 minutes or until hot air comes from the heater.
  1. Return to idle and verify hot air is still coming from the heater.
  1. Set the heater temperature setting to 24°C (75°F) and allow the vehicle to idle for two minutes.
  1. Shut the engine off and allow to cool.
  1. After the engine has cooled, add coolant to the degas bottle to bring the level to the cold fill MAX mark.
 
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