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?!?!?!?!.
If I understand what you've posted correctly it doesn't sound like the thermostat is the problem.
You don't specify what kind of vehicle it's in.
You say that the temperature gauge is staying in the normal range.
Guessing that it's a car (Charger, Magnum, 300).
Is there damage (crack, hole) in the coolant reservoir anywhere?
There are two chambers in the reservoir, one pressurized and one is the overflow bottle.
The pressurized is obviously where the radiator cap is.
If there's a hole or crack in it the cooling system won't build pressure.
The side closest to the outer fender is the overflow area.
If it looks full cooling system pressure has filled it, it shouldn't be full.
You need to know exactly where the coolant is coming out from.
You also need to check the system with a coolant pressure tester.
It will help diagnose where coolant is coming out at.
You can probably rent one from an auto parts store (usually rental is free with a deposit).
