'69 'vert rear vents
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,211
Likes: 6
'69 'vert rear vents
I don't see much written about the rear vents that exit out the rear deck. On mine I can see they are bubba'd and appear to be broken.
What I was wondering is this: would these be a source of a vacuum leak assuming the connection was still intact? I saw what appears to be a vacuum connection going that way in (maybe) the AIM book. It looks like a diverter connects the vacuum hose under the console. Under On my car's console I see no such thing. But I do have the vents and vent grills. I assume they stay shut unless vacuum is cut?
Can anyone clear the air on these vents so to speak? How did they work anyway?
Thanks, Mark
What I was wondering is this: would these be a source of a vacuum leak assuming the connection was still intact? I saw what appears to be a vacuum connection going that way in (maybe) the AIM book. It looks like a diverter connects the vacuum hose under the console. Under On my car's console I see no such thing. But I do have the vents and vent grills. I assume they stay shut unless vacuum is cut?
Can anyone clear the air on these vents so to speak? How did they work anyway?
Thanks, Mark
Drifting
Joined: Oct 2003
Posts: 1,426
Likes: 1
From: VetteMOD
St. Jude Donor '05-'07
I am interested in this also, I have a 68 that has passive vents in the back. Do these vents work (either passive is vacuum operated) and what do they do? Would I be better off closing them?
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
I'm basing this on my memory and some research I did when I removed my shifter console.....
....this is the Astro Ventilation system and the rear flap is cable operated through the heater control unit......I think via the thumb wheel on the passenger side......the flap is opened or closed depending on the setting you select on the thumbwheel..........it works on the basis that a low pressure area develops above the deck and when the flap is open, air is then drawn out of the cockpit........
There are vacuum hoses in the system, operated by the thumbwheel on the drivers side, and these have to do with the heater ducts and recirculation of air (behind the dash)........
The first photo shows the vacuum hoses attached to the drivers side heater control unit (sorry, I don't know the vacuum source).......the second photo is what I remember being a cable going to the rear deck.....
BTW, the only way I can prove this is by removing the console again and that ain't going to happen
....this is the Astro Ventilation system and the rear flap is cable operated through the heater control unit......I think via the thumb wheel on the passenger side......the flap is opened or closed depending on the setting you select on the thumbwheel..........it works on the basis that a low pressure area develops above the deck and when the flap is open, air is then drawn out of the cockpit........
There are vacuum hoses in the system, operated by the thumbwheel on the drivers side, and these have to do with the heater ducts and recirculation of air (behind the dash)........
The first photo shows the vacuum hoses attached to the drivers side heater control unit (sorry, I don't know the vacuum source).......the second photo is what I remember being a cable going to the rear deck.....
BTW, the only way I can prove this is by removing the console again and that ain't going to happen
Le Mans Master
Joined: Sep 2002
Posts: 5,236
Likes: 898
From: Myrtle Beach SC
Originally Posted by marky mark
I don't see much written about the rear vents that exit out the rear deck. On mine I can see they are bubba'd and appear to be broken.
What I was wondering is this: would these be a source of a vacuum leak assuming the connection was still intact? I saw what appears to be a vacuum connection going that way in (maybe) the AIM book. It looks like a diverter connects the vacuum hose under the console. Under On my car's console I see no such thing. But I do have the vents and vent grills. I assume they stay shut unless vacuum is cut?
What I was wondering is this: would these be a source of a vacuum leak assuming the connection was still intact? I saw what appears to be a vacuum connection going that way in (maybe) the AIM book. It looks like a diverter connects the vacuum hose under the console. Under On my car's console I see no such thing. But I do have the vents and vent grills. I assume they stay shut unless vacuum is cut?
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
These vents can be a source of vacuum leak. But they are fuctional only on non air cars. They are controlled by the heat/temperature wheel. Anytime the heat/temperature control **** is place anywhere but in the coolest setting, the doors are open. If you choose any heat at all, the doors go closed. They close by a vacuum signal being placed on the little can at the doors. Where the source is at is fuzzy to me. It seems that if I remember correctly their is 1/8 or smaller line coming out into the engine compartment. Connecting to a T just inside the engine compartment. I looked and can't find it in any of my pics. Hopefully someone can elaborate.
Safety Car
Joined: Oct 1999
Posts: 4,101
Likes: 10
From: NorCal
I did some extensive testing on these openings. Mine is a 'vert with A/C, so the two slots are blocked off with plates. I went ahead and removed the plates and hung yarn strips across the openings hanging down. What I found (all with the top up) was this:
With the side glass up and the vents off, it actually drew in (hot) outside air. Probably why they are closed in the 'off' position.
With the glass up and the vents on, it moved air out, but just barely. Downside was that it allowed even hotter air in thru the vents! Turning the A/C on solved that.
It really moves air out when you open the side glass.
Only reason I tried it was to get rid of the hot dead air behind the seat, but it really didn't help much.
Hans
With the side glass up and the vents off, it actually drew in (hot) outside air. Probably why they are closed in the 'off' position.
With the glass up and the vents on, it moved air out, but just barely. Downside was that it allowed even hotter air in thru the vents! Turning the A/C on solved that.
It really moves air out when you open the side glass.
Only reason I tried it was to get rid of the hot dead air behind the seat, but it really didn't help much.
Hans
Melting Slicks
Joined: Jun 2001
Posts: 3,281
Likes: 6
From: NC USA
The vents are non-functional on AC cars and there is no vacuum connection to the rear.
While you're there, make sure the drain hoses are hooked up at the bottom of the openings and are not clogged where they empty at the fender wells behind the rear tires.
While you're there, make sure the drain hoses are hooked up at the bottom of the openings and are not clogged where they empty at the fender wells behind the rear tires.
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Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
Originally Posted by BBShark
I am interested in this also, I have a 68 that has passive vents in the back. Do these vents work (either passive is vacuum operated) and what do they do? Would I be better off closing them?
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,211
Likes: 6
Thanks for all the good info. I have a non-air car ('69 'vert). I may have to take the console apart anyway to try and find a vacuum leak and when it's off I can do a better investigation of what's hooked up and how,etc.
Thanks so much for the advice, info and pictures!!!
regards, Mark
Thanks so much for the advice, info and pictures!!!
regards, Mark