This apparently was caused by the loose radiator cap, and that is not going to damage the thermostat. You are right about the air pocket. I do not know why you did not list the engine size when you have an engine-related problem, but the V-8 engines usually self-bleed by themselves. If it is necessary to bleed the cooling system, there will usually be a bleeder screw on the thermostat housing. When there is not, look for a threaded plug or a temperature sensor on or near that housing that can be removed. If you need to remove a sensor, unplug it and do that while the ignition switch is off to avoid setting a diagnostic fault code that could confuse someone in the near future. Most fault codes self-erase after fifty engine starts, but it is easier to just avoid setting them in the first place.
Saturday, December 15th, 2018 AT 11:44 AM