Air Conditioning Vacum diagram for 1970

[Big Jim]

Can anyone send me a diagram for a 1970 A/C Vacum Line Diagram?

[Mo's70MCs]

Can anyone send me a diagram for a 1970 A/C Vacum Line Diagram?

 

Jim, is this what you're after?

 

[Big Jim]

Yes Thank You

[cudax]

Here is the one for a 70.

 

Mike

 

http://i304.photobucket.com/albums/nn194/mccuda/ACVACDiagram.jpg

[Big Jim]

It looks a little different from 1972.

I forwarded it to my friend Ned who has a danglng hose that looks like it has a yellow stripe and a firewall gromet attached to it. It hangs below the glovebox.

[MagicDragon42]

Rod, are you certain this is for 1970? The reason I ask is it does not show the vacuum line going from the AC max control position to the heater hose control valve mounted on the right fender well. It also shows the vacuum check valve but not the vacuum storage canister. I believe the diagram you have is for late production (April 71)1971 and 1972.

 

Mike

[Mo's70MCs]

I believe the diagram you have is for late production (April 71)1971 and 1972.

 

you are absolutely right..It does make more sense. Good eye, I know I have the diagram for the other, but where it is, is the question.

[Big Jim]

I have another 72 Monte and have replaced all of the under hood AC parts and charges well but not blowing well through upper vents. I pulled Dash pad and Middle vent and see a actuator door that apparently goes to AC box and it will not open all the way no matter where I have the controls are but will close when set on heater. Could this be an actuator gone bad? Everything else seems to work fine.

[Big Jim]

I changed the source vacum line up to the tee near the switch and still not opening all the way. I guess it could be a bad actuator or a vacum switch under the the control panel. I was hoping it would be something simple. Maybe I'm not getting enough vacum but everything else seems to be working. Defrost and defog, Heater. The door closes when on heat. I feel like the door needs to open all the way on Max. Any suggestions?

[Big Jim]

Well we found the problem was not the actuator but the blend door pin. Making a new pin.

[Jeffrey Aldrich]

I have two small 1/4 inch lines that come out of the firewall, can anyone tell me where they go?  And I'm not talking about wiper splash hoses. these look like a/c hoses?

[jft69z]

Here's a good diagram from the 1970 Service manual, which is the only one that also shows the vacuum hose routing (71 & 72 manuals don't show it, nor do they show the fan selector switch pin-out).

To answer your question, the hose with the white stripe would go to the water cut-off valve (upper left), and the other hose will go to the vacuum source, usually on the intake manifold. That needs to be attached (as we discussed on the phone) to make all the interior blend/diverter doors work properly.

 

1970 HVAC wiring and vacuum diag..pdf