Just did my head gaskets (lovly way to spend a week end) but now i have another problem , no heat the heat was working fine before I did the gaskets I tok off the hoses and tried fillig one side but it just doesnt seem to want to fill . Took some low pressure and presurized the core ,it gave me on big spalsh out the one side and then little air comming out the one side, Is it possible to have a cloged heater core? Does it go from fine to clogged?,whouldnt it get gradually clogged e.i heat gtting gradually cooler? im at a loss and the wife is ready to hand me!