Factory AC removed, no heat!

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PDDart

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Have a '71 Dart 318 car and the factory AC was removed before I purchased the car. The dash controls are still installed but the heater does not work. There are two small vacuum lines (side by side) coming out of the firewall that are cut. What do I need to do to get the heater going? Thanks for any assistance you guys can provide
 
The switch is run by vacum so yep probably the 2 lines are your problem. I am sure someone knows for sure but I will look it up if no one else responds.
 
you can stake open the vacuum actuator for the heat control (heater control valve). Or just apply vacuum directly to it from the engine. I don't remember if it is inside the dash or in the engine compartment, follow the heater hoses into the firewall. The blower motor should be wired and works fine? correct?

what your looking for should look like this or simular. just a simple on off water valve that works from vacuum.
http://www.autopartsnetwork.com/1971-dodge-dart-hvac-heater-control-valve/avaagyCD5uTGJ

Or try to connect vacuum to the hoses you have going into the a/c /heater controls at the dash and see if you can get vacuum going to the valve. From what I see in the service maual the HCV is in the engine compartment so one of the two cut vac line you see one should go to it and the other would be engine vac going to the main switch.
 
The two vacuum lines at the cowl are for the climate system. One goes from the intake to the "harmonica" in the center of the dash (the lever or pushbuttons for Vent, A/C, Def) , the other comes from the harmonica to the heater control valve.

You can either by-pass the heater control valve with a single length of hose under the hood or block the valve open. IMO, the vacuum line to the "harmonica" is more critical as the vent flaps for the heater, defroster, and the A/C vents are controlled by vacuum dashpots under the dash.
 
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