My 87 is not blowing heat from the heater core. I replaced the core and heater valve this weekend with a clean junkyard unit. Run the engine till it’s warm, then turn the knob to full heat. I can hear the flapper move and the airflow changes, but no heat. I let it get hot and opened the bleeder valve till warm water flowed out. The cooling system is new (incl. t-stat) except for a few of the small hoses near the firewall. The two hoses near the firewall connecting to the heater core don’t seem to be warming up. Any ideas? Is the back half of my engine not getting coolant flow and will melt? The long hose leaving the heater that runs horizontally back to the thermostat housing didn’t seem to get hot either. Any ideas?
No interior heat
Ranger
#2
The heater hot/cold knob controls a valve that allows water to circulate thru the hoses that go thru the firewall. Either that valve isn’t opening, or it’s not being told to open.