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73-87 Chevy _ GMC Trucks => Interior & Equipment => Heating, Ventilation & Air Conditioning (HVAC) => Topic started by: StreetImage on January 20, 2016, 04:12:12 pm

Title: Vacuum line for the A/C controls
Post by: StreetImage on January 20, 2016, 04:12:12 pm
Well its going to start getting pretty cold here and i need heater asap but the none of the controls are working. The vac line that comes out the cab was cut and i'm trying to figure out where it connects to. I know everyone says the vac ball on the right but i don't see how the ball would pull vacuum if it only has one entrance. The vac ball just acts like a reservoir from what i understand. 
edit: I meant i want the heater to blow towards me and not the floor
Title: Re: Vacuum line for the A/C controls
Post by: blazer74 on January 20, 2016, 05:48:49 pm
It has two on the bottom, 1 from the engine(supply) the other ( smaller) to the the cab. 

Could be broken off.
Title: Re: Vacuum line for the A/C controls
Post by: StreetImage on January 20, 2016, 06:42:13 pm
two vac hoses? i thought it was just one. Where is the other one located then? when i google, it just shows the one that comes out the cab by the ac box
Title: Re: Vacuum line for the A/C controls
Post by: LTZ C20 on January 20, 2016, 07:09:42 pm
The vacuum reservoir (ball) has 2 vacuum ports. The is only 1 vacuum line coming out of the firewall, not 2. It's just as Blazer74 stated.

The small line from the cab goes to the small port on the reservoir and a larger vacuum line goes from the large port on the ball to any manifold vacuum supply on the engine.
Title: Re: Vacuum line for the A/C controls
Post by: StreetImage on January 20, 2016, 07:26:02 pm
ahhh ok i understood that a bit better lol ill check it out tomorrow