Hey guys so I did the super 6 conversion in my 70 dart, I took of the ac unit to make space. After the conversion and my engine rebuild my heat or heater doesn't blow. If I choose ac on my ac unit it works so I know the blower works but when I choose heat it's completely dead

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1970 Dart Swinger Matching Numbers..

Is the fan working?
Is the heater valve opening when you slide the heater control ?

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Fast is fine but accuracy is final. You have to learn to take your time ... in a hurry
- Wyatt Earp

Pull out the heat control and look for 2 electrical connnections on the back of the main control. The blower power from the fuse has to go through this blower control switch that is built into the Heat/Defrost/Cool air control; it is 'on' in these 3 selections + AC, and 'off' when you select OFF so that the blower stops in OFF.

There will also be a piggybacked switch that is there for the AC compressor. It almost sounds like the blower power circuit is connected to the AC compressor switch instead of the regular blower control contacts. (Or maybe there is a parallel blower contact in the piggybacked switch.) The main blower control switch in the Heat/Defrost/Cool air control often gets corroded and sometimes melts the pastic and gets all misaligned so you have to take it apart and try to fix it, or replace it.

There is a sticky thread on the Electrical sub-forum on the ForABodiesOnly site on how to repair this switch. And you can find them to buy.

And, of course, check the blower fuse first!

The Fan is Working!! and i do see the valve move when i chose heat..the valve is vacuum controlled right?

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1970 Dart Swinger Matching Numbers..

Correct. So what made the fan work? Just curious....

no the fan has always work, it just does not work when i choose heat.

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1970 Dart Swinger Matching Numbers..

Yeah everything seems to work fine except i cant get hot air to come out of my car when i choose (heat) nothing comes out no air (blower) and no heat yet if i choose (a/C) or defrost then everything works fine

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1970 Dart Swinger Matching Numbers..

Didn't these cars use the standard heater control valve under the hood?
In the heater hose. It should have a couple of vacuum lines on a thermostatic valve. They fail and this is the classic symptoms. You can jump the vacuum lines together and it will enable the blower.
I'll try to dig up a picture.

Edit:
Should look something like this, note the two vacuum connections on the side, jump them together.

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Mattelderca
78 NYB (gone now), two S series, three old Snow Cruisers and a Doo.

how can i jump the lines?

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1970 Dart Swinger Matching Numbers..

Are they there? Do you have this type of valve and sensor?

If so, just use a short piece of vacuum line or a small tube to connect them together. If they are hard tubing with rubber ends I have removed one end piece and plugged the hard line into the other end piece.
I have also seen some people who want the OEM look under the hood, take the sensor apart and gut the inside. This allows the vacuum signal to pass through the sensor.
The idea of this sensor is to keep cold air from blowing out the heater until the coolant is warm enough to heat the air. No cold air on your legs. But as you have witnessed, the defrost mode bypasses the feature.

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Mattelderca
78 NYB (gone now), two S series, three old Snow Cruisers and a Doo.