my car ran hot themostat had stuck. we replaced the thermostat water pump n radiator cap. what do i do now?

You have an air lock in the system. Go to advance, autozone, or harbor freight and they have an air bleed kit for this. This is the only way to get all the air out.

we have burped it for days yet the air keeps coming back everytime we test drive it...do I still need to do that?

Yes,with this tool it will get all the air out without a mess.

if after you are sure you have air out of block then yes it may be head gasket. try this trick to get air out. raise front of car so that rad cap is higher than all else. leave cap off and run car till hose coming away from thermostat is hot, top off radiator. You should now have heat no air lock and temp should be normal. If no heat , using hand feel both hoses going into and coming out of heater. if one is hot and one cold or very much cooler than heater core plugged.

sounds like thermostat is in back ward .

Mark , Can't be backward housing will not fit