Oh yes, forgot to mention. .... engine warms up pretty fast getting warm and the radiator water is still cool. The lower hose feels warm and the upper cold and water in radiator seems cool....
sounds exactly like the pump isn't pumping [rather than pumping too fast], or you added the SolderSeal when the engine was cold and low and it totally plugged the rad as George said
the lower hose should be cooler than the upper hose, and if the engine is overheating with no stat, that overhot water should be getting pushed up the top hose to the rad - everything would be equally hot, nothing "cold" or even "cool"
pull the bottom hose and see if water flows thru the rad freely - check if the pump is actually pumping
Bill