standup

There's a 4 line vacuum pod attached to the heater control unit in the center console on my '71......what is this for and how does it work????

The first member to answer the question correctly will win THE PRIZE.........

BTW....this a non A/C car....


[Modified by standup, 3:34 AM 8/25/2003]

Viken

In my '80 this controlled the vents. When vacuum is allowed to them, they close/open. One is the outside air vent (naturally open/closed on vacuum), another is the inside air vent for recirculation (naturally closed/open on vacuum). I think this is an incomplete answer, I think there is another vent somewhere controlled by vacuum that opens the path to the main a/c ducts, but haven't found exactly where it is yet. (In the process of doing A/C system, and can't figure why it only blows on my feet...)

carl a

they control your vaccume acuators for #1 heat defrost#2-fresh air recycle air( this one works when you are on max air) the kick panel will open and the wiper bay will close- one of them is the sorce vaccume(supply) ill try to send you a e mail on the heating vent system--- also it helped me by using the vaccume diagram in the assembly manual-- i color coded all the vaccume lines the same color as they are in the car and it was e-z to trace out--hope it helps--carl

Ganey

Evidently yours does not work. This may help though written for 77 up & you may have a metal "rivet" in 2 below.


FAST FIX by GANEY
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine is damaged from heat - a small plastic tube that goes in below the hood theft switch into wiper valley. Replacing most of engine side w/ hose will fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or lube w/ a thin layer of white lithium grease or vasoline to fix.
3) If you have a heater, the hose to heater hose valve underhood probably also needs replacing. Block w/o heater.

PS The design problem comment is not intended to be offensive to any of our northern friends.
:cool:

LAvetteman

Astro ventallation. Opens the vent in the rear deck.

Eddie 70

Turning the heat dial works the Astro vent.

LAvetteman

No, to my knowledge the heat/cool **** operates the heater circulating valve. The other **** is what has the vacuum lines hooked to it, I think.

standup

There's vacuum pods in front of both thumb wheels...I didn't make it clear that I was referring to the one on the drivers side......

The heat/cool **** has a wire attached to it similar to the vent *****.....the wire and the vacuum lines run towards the dash though, not the rear.......

At any rate, I can tell that trying to understand this system is going to be a long term project....and since my goal is to tidy up the center console, I think I'm better off concentrating on something simpler.....like putting it all back together as fast as possible so I can drive the car :)

Thanks for the responses........

standup

BTW, carl a won THE PRIZE......he sent me a detailed e-mail on the system and how it works.......THE PRIZE is a copy of New Zealand Classic car magazine featuring the Corvettes of NZ ...........

Thanks to everyone for their posts, they have been helpful, but obviously, there can only be one winner..........


[Modified by standup, 2:57 AM 8/29/2003]