Just finished my 350 swap got it all back together as the 305 came out, replaced radiator hoses, radiator, thermostat, checked all vac and hose lines, did full flush on system with correct mixture added. To no avail i have no heat, blower motor turns on but blows cold air only, is there any way to check the heater core? Any other suggestions would help, gettin chily in the morning here and cant drive it with the tops off Thanks for all ur help

 

check the hoses coming in and out of the heater core. the core could be stopped up. make sure your mixture falp is moving and if you have a air compressor you might blow some air through the heater core and see what comes out

 

The Heater Control Diverter Valve might be stuck in the closed position preventing coolant from flowing into the heater core. Just replace it with a new one.