Challenge for C3 owners
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
Challenge for C3 owners
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]
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]
Advanced
Joined: Aug 2003
Posts: 71
Likes: 0
From: Kailua Hawaii
Re: Challenge for C3 owners--WIN A PRIZE (standup)
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...)
Safety Car
Joined: Jun 2002
Posts: 4,135
Likes: 1
Re: Challenge for C3 owners--WIN A PRIZE (standup)
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
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
Re: Challenge for C3 owners--WIN A PRIZE (Viken)
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:
... (In the process of doing A/C system, and can't figure why it only blows on my feet...)
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:
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Re: Challenge for C3 owners (LAvetteman)
Astro ventallation. Opens the vent in the rear deck.
Safety Car
Joined: Jan 2001
Posts: 4,660
Likes: 3
From: South Central Louisiana
St. Jude Contributor
Re: Challenge for C3 owners (Eddie 70)
Astro ventallation. Opens the vent in the rear deck.
Turning the heat dial works the Astro vent.
Turning the heat dial works the Astro vent.
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
Re: Challenge for C3 owners (LAvetteman)
Astro ventallation. Opens the vent in the rear deck.
Turning the heat dial works the Astro vent.
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.
Turning the heat dial works the Astro vent.
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.
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........
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Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
Re: Challenge for C3 owners (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]
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]