Remove the cable and see if the door is moving from one hard stop to another. The cable should be adjusted to push the mixer door all the way to the hard stop.
I'm not seeing any door open, Where is the actual open supposed to be, the lever is moving very smooth but still not seeing anything actually open (glad i'm not out of shape, going up/down 3 flights of stairs every time i go to look at something!)
The "door" is a flapper inside the heater/AC unit that directs the air thru the heater core or not. The only thing you'll see move is the external lever.
Phew, i'm not just blind this time. Well the lever does move smooth all the way through from what i could tell playing with it, constantly moves from hot to cool, not just moving at hot or at cool.
If you pull the cable off the mixer door lever you can move the lever from one extreme to the other. Should bump up against a stop at each extreme. That SHOULD control the mix of heated and cool air coming out the vents, IF ITS ADJUSTED RIGHT. Adjust it, by moving the cable in its mount, so the mixer door just makes firm contact in the COLD direction.
Hmmmmm...I'll take a look, When you say at each extreme, does that mean that it should stop just at hot and just at cold?
I adjusted it so it was good on both stops, then i realized that that was controlling my defrost/heat/off marked lever rather than my warm/cool lever.
On my '72 AC car the mixer door is controlled by the warm/cool lever. Thought I could help you but yours must be different.
Could be just the fact that i dont have AC...However that switch needed adjusted as well so i wont complain. And it might do me some good as i can shut my heat entirely off now.
