I rebuilt my 4runner this winter. While I had the motor out, I did head gaskets and valve cover gaskets. Started for the first time today, ran for about 10 minutes and it got hot, shut it off, cracked the cap and steam from the overflow. Upper hose was hot, lower was cool, figured it was a tstat. Went and got one, replaced it, when I pulled the old one out coolant gushed from the block, like it was stuck shut, new one in, still does it, new cap as well. When I squeeze the upper hose with it running it gushes like the water pump is working, but it acts like it has an air pocket. My old gtp had a bleeder to let the air off, and I cannot find one on the 4runner, or maybe I have another problem. I dont want a milkshake so please, anyone have any ideas?