alright so....in now in Edmonton, Alberta and its cold as balls....i have no heat in my truck. the heater worked find when i was on the coast and then i installed a circulating block heater in the truck. drove all the way out to edmonton with NO heat and now im having trouble getting the heat to work again. i did not drop all the coolant when i did the block heater, just spliced into the heater system. i have tried to get any air out of the system by letting the truck run with the rad cap off, i have left it run for 15-20 minutes twice now and still blowing cold and coolant is overflowing out of the rad. im not sure what to do and i dont have tools or a place to work, so im working on the street in -20 weather...any advice would be much appreciated, i dont think its the t-stat because i will get warm air SOMETIMES from the heater but usually just cold...im kind of to the point where i might just take this into a shop because im going to be driving about 4 hrs north in the next couple days and NEED heat...thanks guys!