I have a 1970 camaro with factory ac. While installing the ac system in the car, I decided to test for leaks by connecting a vacuum pump to the ac vacuum line that goes to the engine. When I did this, I have a small vacuum leak. So I took the control switch assembly out of the dash and pulled the hoses off of the distribution valves (the rotary pieces that are moved when you move the function and temperature levers on the control panel). I tested each port and all of the hoses and vacuum actuators are fine, no leaks. I then tried vacuum testing the rotary distribution valves themselves (there are two, one for function (off, ac, vent, heat) and one for temperature (cold, hot)). These are what the vacuum lines connect to on the ac control panel in the dash. When I connect the vacuum pump to one of the ports and plug all of the other ports, I get a slow vacuum leak. It’s leaking between the two halves of the rotary distribution valves. These are just metal halves with a spring loaded center pivot. So I don’t see how a new one would be any better. Does this seem normal?