Missing hvac vacuum motor?

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Wwiifan

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How many vacuum motors should I have in this truck? In the hvac air box are 2 vac motors, the defrost and the heat and ac, and one on the pass. Side kick panel, which I think is the recirculating one. The closest vac diagram I have show a 4th vac motor called the outside air actuator. Where is this suppose to be located at?
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Craig 85

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That's in the outside cowl area.
 

Wwiifan

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As in under the piece between the windshield and the hood?
 

HotRodPC

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I sure like that diagram though. I wish I had that when I was doing my heater core. I made a mess of those vac lines.

To this day, If I run my defroster on, I have to shut the engine off to get the blend door to go back home and push air to the floor or bilevel. Strangest thing ever I thought. It appears to me, the defrost actuator will pull the door, but when released, unless the Heater side actuator pulls the door shut, it'll just stay up there in defrost mode. I'll fix it someday.
 

Wwiifan

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Sweet! I just found a pic of the outside air actuator on a squarebody from a Google search the tool me to another gm squarebody forum thread. I hope mine works
 

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