Join Date: Feb 2018
Location: East TX
Bronco Info: 1980 Bronco Ranger XLT, 351M, C6
I’d surmise it’s hard to determine if the evaporator is inefficient until the air volume is fixed.
My heater box was chock full of what I’m guessing was bird’s nest material.
You may also have a blend door stuck, ducting in the dash separated, etc.
My EVTM describes a load test that can be performed on the blower to determine (iirc) it’s pulling appropriate amps.
EDIT: one simple test may be to remove the resistor from the heater box and run the blower on high. See if you can block as much air going into the cab as possible. Compare air flow out the resistor opening with what you feel in the cab. It’s a rough test for sure, but may can narrow down where your volume issue resides.
1980 Ford Bronco Ranger XLT, 351m, C6. My name is Ferguson.