92 grand am cooling problem

Hi, I recently fixed two broken bolts on the thermostat housing on a 3300 grand am. After the repair I found the engine was still overheating. I replaced the water pump which was leaking at the weep hole and still have a problem. I did a compression check and its good. I checked cooling system with a pressure check and its good.(holds pressure).

Now my question, Is there a proceedure to purge the air out of the cooling system?

I also replaced thermostat when housing was repaired, and a known good radiator was tried.

Thanks

did you check for debris between the radiator and a/c condenser? Are your fans working? Did you put the t-stat in properly, with the spring toward the engine and the point toward the radiator?