66 T-bird heater temp control does not work

[dzolotarchuk]

I have a '66 T-bird with A/C, but I cannot get any heat in the car. The control that directs flow for floor/defrost/etc. works fine, but I cannot get any heat, just vent. I've diagnosed that I'm not getting vacuum at the coolant valve under the hood. If I apply vacuum there it works fine. I've removed the control in the dash and applied the supply vacuum line directly to the brown line which is supposed to activate the coolant valve and when I do this the heater also works, so I think the vacuum control in the head unit is not working properly. The tab which is supposed to ride on the cam at the back of the lever does not appear to be making contact, which I think is part of the problem. I think there is a diaphram/spring set up which is attached to that which may be shot. Anyone know someone who rebuilds or sells rebuilt units?