[Longs]

I recently discovered that the vacuum tee that provides vacuum to the line through the firewall ('67 with A/C) was broken, meaning that I had a vacuum leak under the hood. I put in a new tee, started the car, and heard a vacuum leak under the dash on the passenger side.

I removed the duct work and glove box and discovered that the leak was at the back of a "vacuum pod" that has five lines, at the back corresponding to the line coming through the firewall (the line with the check valve). The other lines all appear to go vacuum actuators that control the various doors. I could cover the hole on the back side coinciding to the input line and feel vacuum. I put a piece of tape over the hole to stop the hiss, but I assume that the pod is still broken. I don't seem to get any vacuum at the various actuators.

How does this vacuum pod control the direction of vacuum? It seems like it's just like a junction block, no electrical connections, etc.? I'm sure that i have to replace it, since it's leaking vacuum, but I'm not getting how this works. See the attached diagram.

Thanks for any help anyone can provide!

[fyrffytr1]

It directs vacuum to the different actuators as you move the lever on the dash control. Here's a link that was given to me showing how the vacuum routes. Scroll down to page 1b-27 to start the Tempest schematics.
Now, my question.Does anyone make this part? I have not hooked mine up yet so I don't know if it is good or bad.
http://www.thefirstgensite.com/libra...67S1BP1_30.pdf

[Longs]

Thanks, the schematic I attached is from the same source. I'm still not able to determine how vacuum is switched by that vacuum hub. How are the control panel positions (de-ice, vent, heat, inside, outside) telling it what to do, or is there some other component somewhere that's switching vacuum?

[Old Goat 67]

Here's a top shot of that mechanism. The arm from the lever is what controls that port operation.
Seems I remember taking that apart to lube the rubber parts when I was refurbishing my dash. Very carefully!

You'll have to get it out of the dash to do that. Oh, the joy of restoring a 47 year old car.

Charles

[Andre]

You can fix this without buying any parts. All the hub does is provide and easy plug so that there is no thinking on where each line has to go on the control head to make it work. Unplug your hub, so it is hanging down. You can carve away the broken piece. and attach your vacuum line directly to the control head. Leave the rest of the lines plugged into the hub and reinstall it
I hope my explanation is easy to understand.
If you don't want to do that, I am sure I have a spare hub laying around

[Longs]

All I see is a vacuum line coming through the firewall, then other vacuum lines going to the various door actuators. What are you referring to as the "control head"? Is there vacuum running up to the selector (de-ice, vent, inside, outside, heat)?

[Old Goat 67]

I believe what Andre is referring to as the hub is the rubber piece that all five vacuum lines go to, which plugs onto the ports in the picture I attached.
If you use the use the diagram you posted and look at the picture I posted, you can tell where each line goes to what port. All the mechanism does is direct vacuum to each line as it needs to make that setting function. As shown below.

[fyrffytr1]

Here are some pictures that you may find helpful. First one shows the control head from the top. Second shows the rubber block with the five lines coming off of it and the third shows the numbered ports that the block plugs into. The block will only plug in one way.
It is hard to see the numbers on the schematic in your original post so I will try to get them right.
#1 goes through the firewall to the main port on the actuator.
#2 also goes through the firewall to the small port on the same actuator
#3 is the main vacuum source from the engine.
#4 goes to the end actuator under the dash closest to the driver
#5 goes to the actuator behind the heater box. The port for it is on top of the box for easy access. If you take the glove box out you can see it.

I hope this is of some help to you. It took me a couple attempts but once I got the rubber block oriented to the ports it was easier to hook the lines up correctly. I don't think the block is reproduced and my old one is cracked or I would offer it to you.
One other bit of advice and I will shut up. While the rubber block is off the panel put a few drops of oil on the little felt pad in the middle of the numbered ports. That will help seal it and prevent a vacuum leak there.

[Longs]

Thanks, this was tremendously helpful!

What I never understood until seeing your photos was that the rubber block is supposed to be attached to the control panel! I don't know how, but somehow it must have dislodged because it was just hanging loose behind the dash, and I'm assuming that the vacuum leak is from the port where it's supposed to plug onto the control panel. I'll have to see how difficult it's going to be to get it back up and attached.

[fyrffytr1]

It is easy to attach. Just line the holes up and push it down. Lining it up is the hardest part. Don't forget to put a couple drops of machine oil on the felt gasket in the center of the ports on the control panel.

[Longs]

Thanks - I'm going to be trying to reach up under the dash to do this, so we'll see how that goes! Am i correct that the control panel only comes out by removing screws behind the dash? There's nothing that I can see on the face of the dash.

[Old Goat 67]

That is correct.

[Jeff Hamlin]

You may have better luck by removing the glove box/liner.

[Longs]

Thanks Jeff, I was thinking the same thing - it's not that difficult to drop the ductwork and then take the glove box liner out. It's not that easy to manipulate the glove box liner through the opening, especially being careful not to fold or otherwise compromise it.

[fyrffytr1]

You may be able to push the glove box back far enough to see the control. I have a radio plate in my glove box so it was no problem moving it.

[Jeff Hamlin]

If you look at the side of the liner there should be folds/creases, these are so you can fold the liner down to remove from the door opening, just go slow.

IIRC you should not have to remove any ducting to access the vacuum port.
But I haven't had to do anything under my dash in awhile,
so don't hold me to the last statement

[fyrffytr1]

i just realized that when I put my vacuum lines in the A/C plenum was not installed which made the job very easy. I looked this evening and the plenum is in the way. I think removing the glove box is the best way to go.

[Longs]

I was able to remove the screws in the glove box and push the liner back far enough to reach the controller, and thanks to the photos, I knew how to get it back on, the whole thing took less than 10 minutes.

My diverters all work again. And after reading that the compressor clutch would still engage with low freon, I decided to unplug the connector at the compressor. I know it doesn't work so I'd never put the A/C on "Outside" or "Inside" but you never know, someone could inadvertently move the lever without me noticing. At some point maybe I can get the A/C repaired.

Thanks to everyone here for the information!