overheating no heat

[hondatuner94]

hey i have a 94 civic with a 1.6 ltr v-tec i just put a new engine in it with 40 thousand miles. the car runs fine and has plenty of power. there is no smoke or antifreeze in the oil. but i do not have heat and after driving the car for 15-20 mins the engine heats up. i have changed the thermostat 3 times. any ideas?? i have been told to bleed the coolant at the thermostat houseing instead of the bleeder on the front of the engine to get the air out of the hoses?! sound like it would work?! any help at all at this would be great
chris

[mintoxik]

maybe your heater core??