Ac wont divert to upper vents

[john1962]

Hello...........on my 79 vet the Ac only blows out the lower outlets. I pulled off the rubber hose assembly that has the 4 hoses attached that plug into the control unit, and I have vacuum thru the #3 hose only, this hose runs up to the actuator asemly by the diverter box. As I slide the control unit lever thru all of the positions nothing changes. Ive even manually moved the actuator arm with my hand up and down but still get no change in where the air is blowing. Any ideas? Thanks
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