Temperature Knob

Anyone know what the temperature knob on the dash is for. It appears to be a pull type, but I cannot get it to move at all. It has a gray cable connected to the back of it. It is next to the defrost pull knob and another one that I can't think of at the moment. Thanks!

temp would open the valve for water to flow to the heater core .Defrost to send all air flow to the windshild and the 3rd would be volume of air and low ,med, hi speeds thy to get some oil in that cable and on top of the heater core andat the valve it's near the core as well, and just keep working it . If the cable is not plastic coated then oil it thru the sheathing.

Thanks, I'll try to oil it. I believe it is plastic coated. I'll have to trace it and check the other components too (at the heater core). Thanks again.

I'd suggest doing this as 2 separate procedures. CAREFULLY remove the cable from the valve and work on the cable and the valve separately. The valves are not available, only some that can be modified to work.
The 2 control cables pull, the fan speed knob turns.
64-66 are 3 across, 67-70 are in a triangle.

Thanks for the heads up...knowing me I would go in there yanking on it. I will proceed carefully...

If you find that the cable moves freely after you disconnect it then it is the valve.

As Rod stated, the valves are made of 'unobtainium', but there is a modification.  The 'mod' required pulling the entire heater out.

Let me know if you have to go this route, I had to, and I have parts numbers and can help.

Thanks, I got it moving. I had to get to the valve, it had a little rust on it. I sprayed it with some Kroil lube and kept working it with my hand, eventually it loosened up. Thanks for all the help everyone!