On my 67 442, the blower fan comes on for low and high operation when I select A/C mode, but doesn't come on at all for heat or defrost when the A/C is switched off. Med fan doesn't work at all... Does that sound like a blower switch?? Anybody got one?? Ideas??

 

Sounds like two problems. The mode switch in the control head is causing the no-fan-at-heat issue and either your resistor or fan switch is causing the lack of medium.
Check the wiring at the resistor to see if it is burned. Remove the resistor to check for opens (inspection).

 

By mode switch, do you mean vacuum, or electric? I see 2 vacuum switches, and 2 electrical switches...

 

The mode lever should have an electrical switch on it to control the fan and also the compressor in AC mode.
Can you see the control panel from behind easily?

 

There are 3 levers on the control head. One is heat, one is temp, and one is A/C. I can see it fairly well from under the dash. I have the radio and ducting removed. I have replaced the electrical switch that is connected to the A/C lever with a NOS one. It seems to control the compressor clutch. It was a simple on-off contact switch. The other electrical switch is connected to the heater lever and seems to also be a on-off contact switch. I can't find a good wiring schematic of the heater wiring anywhere, including the shop manual!

 

Now can you hear the fan running but just no air delivery when in heat mode? I assumed not but want to be sure.
There should also be an electrical "master switch" on the control head. It should be ON in all mode selections. It is possible something is preventing that switch from closing when in other modes.
YOur year control panel is different then mine so I am kinda taking stabs here. The AC wiring diag should be in the A/C - heat section of your manual (assuming its a factory manual).

 

Yes, I can here it running in the A/C mode. It will blow high, or low, but no med. As soon as I leave A/C, it quits. I have the factory shop and body manual, but no heater/A/C diagram. I have also looked online, but no joy...

 

Then on the control head I bet there is a mechanical issue that causes the main switch to open when it leaves AC mode. You would need to pull the control head and check it out. The switch itself is probably good.

 

Probably right. I was hoping to avoid that!

 

I SOLVED IT!!!!!
After chaseing wires, and much effort in 100+ heat, I discovered the master switch was about a knat's wing out of adjustment, and the heater lever would not let the switch close. The A/C lever had much more clearance than the heat lever, alowing the switch to close!!! I moved the switch a bit, and scored!!!! Thanks for all of your help!

 

Great! Glad it was an easy fix!!