Ok. Changed the thermostat and began sudden over heating that l didnt have before. So the video l found suspected air trapped. I got an Allen wrench and ratchet and pulled the purge plug above the thermostat and had some air, so l was excited that l resolved the issue. But on test run, the thermostat stayed middle like it should look, but the engine got HOT AND steamed and smoked from below the Coolant well. What is Going on?!?!?!?!.