Originally Posted by 98CoupeV6
You don't understand. The thermostat measures the temperature of the coolant at the exit of the water pump, right? If the water isn't circulating, you're subjecting your engine to extreme cylinder temperatures. Do a compression test. If you didn't notice any steam that water was going one place...into your engine. You probably blew a head gasket, if you didn't warp the head and/or block.
You are right, I don't fully understand how the complete system works. Who should I contact to get a compression test? How much does that cost? Is it a simple test that the guys at Autozone or O'Reilly's can do in 5 minutes, or must I take it in to a "qualified mechanic?"