MakoShark72

Under the rear deck of the early NON-Air coupes is a vent system, vacuum operated by the console controls for fresh air/recirc, etc...The Air cars had this vent system sealed off, I'm told.

When I bought my 72 coupe, I noticed this contraption behind me, could tell there were 2 "doors" hanging down, and the driver's side "door" was only hanging by one end (a missing hinge pin...more later!) Everything was pretty rusty!

Didnt pay much attention to it, since I began taking the car apart soon after purchase. When I finally got around to doing the interior (3 yrs later!...couple of months ago!) it was time to figure out what to do with the "Astro-Vent" system behind the seats!

When I removed the carpeting, I had noticed a very small metal vacuum line running from where my vent controller USED to be, along the center transmission hump, across the vertical surface behind the driver's seat, up along the driver's rear wheel well, and finally to a little actuator. Its a smaller version of the actuators that "actuate" our headlights and windshield wiper doors. The actuator sits right behind the rubber drain tubes that drain water from the vent wells to the wheel openings..

Anyway, I crawled up in there and began to remove the 8 or so rusty sheet metal screws holding the assembly in place. The assembly actually consists of 2 separate vents, a bracket to hold the vacuum actuator, and the actuator itself.

Here's the driver's side vent assembly still in place. The actuator is at the far end...



Here's the actuator, still in place in the car...



After removing all the components (PB Blaster) it was time to evaluate and start cleaning...



The parts had alot of surface rust, which came off with the help of an electric drill and circular wire brush...







Each vent assembly had 6 little rubber "pull thru" bumper-thingy's that had to be CAREFULLY removed and reused. I couldn't imagine finding these if I had ripped them apart pulling them through the holes!! You can see them in several of the pictures above.

After all (or most) of the rust was removed, I treated the pieces with Rust Converter, then several light coats of Rustoleum Satin Black (what the Hell would we all do without Satin Black??)

Rust converter..



Paint...



Here's the actuator bracket and 4 small retainer strips that hold the little rubber bumpers, mentioned above...



Here you can see the restored vent assemblies with the little rubber bumpers re-installed. The retainer strips are between the body of the vent and the rubber bumpers... Also visible is the new rubber seal that is attached to the top side (the side that goes up against the car) of the vent with self adhesive...



The vent doors attach to the vent body by 2 small hinges and hinge pins. The pins were pretty rusty, so I made new pins by cutting the heads off of galvanized roofing nails, which were pretty much exactly the same diameter..



On the underside of the vent doors, you attach a foam seal, using 3M spray adhesive (thats what I used)...



The door is then attached to the vent body with the hinge pins...here's a closeup of the 2 pieces finally married together...



The finished assembly, prior to installation in the car...



This simply shows the mechanism that allows the driver's side vent (with the actuator) to also work the passenger side vent..



Now back in the car...looking towards the passenger side...the little holes you see, are access holes to get to the screws holding the whole thing in place...



The center where the 2 assemblies meet...



Looking towards the driver's side and the actuator...



The actuator, all cleaned up and reinstalled...



I converted to Vintage Air, and VA doesn't use the rear Astro-Vents. I plan to install a small vacuum switch (the same ones that control our headlights and wiper doors under the steering column) so I can open and close my NEW Astro-Vents!!

I hope this has been helpful!!!


Rob

avner

I restored those metal pieces also in my 72 vert' but on my car they are constant close with screws with no vacuum mechanism, my car was original A/C car but I'm going to install Vintage Air.
Avner

78Vette-SA

Nice job and nice write-up.

Do the vents open without vacuum and then close when the car is started and a vacuum source is applied? Or is it the other way around? I would think open, then closed with vacuum, then controlled by the Astro-Vent controls in the console (talking non-AC car of course).

I know that the vacuum is Tee'd across the heater control and back to the Astro-Vents but wasn't sure what the default position is.

Thanks!

70BBvert

Nice job Rob, same setup is on non-air convertibles. need to rebuild mine as well. Believe it or not those little rubber bumpers are available, along with a rebuild kit. Check Doc Rebuild's website.

Jim

7T1vette

Good work. My only feedback is that the foam seals would be sturdier if "craft foam" were used instead of open-cell foam. It comes in 8"x10" sheets...about 3/32" thick...and you can buy it at Michael's Hobby/Craft stores for about $1 per sheet.

I wouldn't recommend changing yours, but other readers may want to try the denser foam. (P.S. It's the same stuff that is used for the passenger-side kickpanel vent door seal.)

MakoShark72

I believe they hang open, then close with vacuum.

Jim, I had gotten a rebuild kit from Mr Willcox, and the rubber bumpers weren't in it, so I assumed they weren't available. Mine were in great shape (I was surprised) so I removed them, soaked them in hot water and Dawn overnight, and reused them!

Thats a great idea. I used the foam pieces that came with the rebuild kit, but the open cell foam will probably deteriorate quicker. I think it may outlast me this time however!

Rob

70BBvert

I got my kit from Doc R, they weren't in theirs either. Then I saw them in his catalog. Ended up picking up a set at Carlisle. I'll get to this job eventually, working on the rest of the body repairs.

Jim

GPGG70

makoshark72,
Very nice job on the astro vent system. Nice detail and write up for all to enjoy and learn from.
I have not attack mine yet on my vert but have purchased most of the rebuild parts for the system. I found & bought the little rubber bumpers from zip I think but what I've been looking for is the smaller vacuum actuator thats mounted on the side. Mine works ok but will need to be cleaned up like you have done to yours.
Thats a good idea installing a valve or switch to open and close the vents.

tfi racing

Looks good!Thanks for reminding me of yet another one of those jobs I need to get to one of these years...

MakoShark72

No prob....just trying to help!

drspencer

Nice write up.

Dustup7T2

Kudos for the great writeup, Mako. It helped explain to me where that little vacuum pipe running along my tunnel ends up at. Hadn't worked that issue yet and now, I'll have all this fine data to square mine away in the future.

Your efforts are most appreciated!

72ls5fla

great job!

I always wanted to know how these worked and what they looked like.

Alan 71

Hi Robb,
Nice pictures and description. They'll answer a question that gets asked often
I believe the door is open when the heat/cold wheel on the heater control is on cold and closed when the wheel is on heat.
Leave it to Chevrolet to come up with a system like this to take the place of the vent window that disappeared in 67.
Regards,
Alan

MakoShark72

Alan,

Cant attest to that, as the Vintage Air replaces all those vacuum hoses with electronics and servo motors. As stated above, the VA system doesn't utilize the rear vents. Thats why I'm installing a vacuum switch to open and close them when I want... hopefully they will work effectively enough to notice a difference in air flow. If not, well at least they are pretty again!!!

Rob

70Yellowbird

Also, the craft foam that 7T1vette mentions is approx. 9"X12" and can also be purchased at AC Moore, JoAnn Fabric, and Walmart. I bought a multi-color pack (including black) of 12"X24" (2mm thick) craft foam at Walmart, so I didn't have to install it in pieces. But buying the larger size sheets isn't really necessary because having butt joints in this application would not be a problem.

Raphiki

Beautiful job and great pictures! How did you get those pics? I couldn't get into that little space with a pound of grease and a shoe horn!

MakoShark72

My back is still killing me!

1971Coupe

great work

eastltd

Those vent windows were great when your had to flick your smoke outside!:

Nice job on the Astrovents Rob but you don't need them with your windshield missing

When is that going in?