1975 rear deck vents
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Instructor
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From: chambersburg pa pa
1975 rear deck vents
Does anybody know if there is drain holes under the metal vents on the rear deck I wash the car and water just lays there and when I go down the road then it smears down the back of car thanks in advance Keith
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From what I've read the only ones with a drain were those equipped with the Astro Vent option. That being said it seems to me that it wouldn't be all that hard to install a drain hole and tubing on each side if you wanted to.
Drifting
Joined: Jan 2012
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From: Port Huron MI
Hey Keith,
If you have a factory air car (as it sounds like you do), there is no drainage in that area.
I imagine it wouldn't be too difficult to add, though I admit I have found no reason to add them to mine. Hope that info helps. -Stroh
If you have a factory air car (as it sounds like you do), there is no drainage in that area.
I imagine it wouldn't be too difficult to add, though I admit I have found no reason to add them to mine. Hope that info helps. -Stroh
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From: Southbound
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If memory serves, there could be a factory drain on each side. These can get stopped up and allow water to collect in the bottom of the vents. Do you have the assembly instruction manual (AIM)? If the drains were installed, the AIM will show them. I won't be able to get my hands on my 75 AIM until this evening.
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From: Downtown Annapolis, MD. The Future is where we all have to live. Let's not screw it up.
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I have a '71 factory air coupe, so the vents on the back deck are blocked off with a panel from the inside and are thus rendered inoperable from a venting standpoint, but there is a drain for water that you can see if you look in the wheel well above and slightly behind each rear tire.
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Michael S. Palmer
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From: Westminster Maryland
Hi,
The Astro-Vent system was standard, not an option.
Coupes had the drain hoses whether they had a/c or not, while on convertibles the plenums emptied straight down.
A/C cars had didn't have the vent mechanisms, and the plenums were blocked off, but still drained the same way.
Regards,
Alan
Coupe, (no a/c), right-side drain hose leads to wheel-well
The Astro-Vent system was standard, not an option.
Coupes had the drain hoses whether they had a/c or not, while on convertibles the plenums emptied straight down.
A/C cars had didn't have the vent mechanisms, and the plenums were blocked off, but still drained the same way.
Regards,
Alan
Coupe, (no a/c), right-side drain hose leads to wheel-well
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From: Southbound
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AIM shows 75 coupes got the familiar drain hose Alan shows. These were also on the earlier cars.
75 convertibles did not get the hoses, but, based on the AIM illustration, there appear to be two drain holes in the bottom of the rear plenum panel (Callout #1).
75 convertibles did not get the hoses, but, based on the AIM illustration, there appear to be two drain holes in the bottom of the rear plenum panel (Callout #1).
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From: Downtown Annapolis, MD. The Future is where we all have to live. Let's not screw it up.
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Those drain hoses are very soft, so be cautious about putting anything through them like a coat hanger that may puncture them. Just sayin'...
Melting Slicks
Joined: Apr 2001
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From: Olmsted Falls, Ohio
I've heard all this before, but I got to tell you that I have an April 75 coupe with A/C and it does NOT have any drain holes. The only holes under the grill are the 4 screw holes.
And as far as I'm concerned the AIM page that Easy Mike linked is wrong for this instance. A coupe with A/C did not have the "real" vents back there and the deck was blocked. The AIM does not always have things exactly as seen on some cars, especially late in the build year.
And as far as I'm concerned the AIM page that Easy Mike linked is wrong for this instance. A coupe with A/C did not have the "real" vents back there and the deck was blocked. The AIM does not always have things exactly as seen on some cars, especially late in the build year.
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...And as far as I'm concerned the AIM page that Easy Mike linked is wrong for this instance. A coupe with A/C did not have the "real" vents back there and the deck was blocked. The AIM does not always have things exactly as seen on some cars, especially late in the build year.
Advanced
Joined: Aug 2011
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From: Coshocton Ohio
rear vent drains
I've heard all this before, but I got to tell you that I have an April 75 coupe with A/C and it does NOT have any drain holes. The only holes under the grill are the 4 screw holes.
And as far as I'm concerned the AIM page that Easy Mike linked is wrong for this instance. A coupe with A/C did not have the "real" vents back there and the deck was blocked. The AIM does not always have things exactly as seen on some cars, especially late in the build year.
And as far as I'm concerned the AIM page that Easy Mike linked is wrong for this instance. A coupe with A/C did not have the "real" vents back there and the deck was blocked. The AIM does not always have things exactly as seen on some cars, especially late in the build year.
My '75 was like Ken's, A/C, no drains. Additionally, beware if you try to remove the screws holding the grilles! Use plenty of PB Blaster and patience, as you will likely be drilling and tapping out broken screws otherwise. I know this the hard way!
Ken's right, too, about the AIM (or any other manual, for that matter). They tend to be less than "item specific" in a lot of cases, showing the basics common to "most" applications. When you get into the advanced stuff, good old know-how and experience have to be taken out of the toolbox. Thanks, everybody!!
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From: Westminster Maryland
Hi KS and UM,
What you're suggesting is that there were plenums with and WITHOUT drain holes for coupes and convertibles.
I don't see how or why that could be since GM didn't make anything they didn't need and there was no reason for plenums without drain holes.
Sorry!
Regards,
Alan
What you're suggesting is that there were plenums with and WITHOUT drain holes for coupes and convertibles.
I don't see how or why that could be since GM didn't make anything they didn't need and there was no reason for plenums without drain holes.
Sorry!
Regards,
Alan
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From: Coshocton Ohio
Hi, Alan!
Sorry if I was confusing. Astrovent cars had the plenum set-up with vacuum actuated doors, grilles to the outside, and drains. My '75 with A/C didn't have Astrovent and consequently didn't use a plenum that I ever saw. The rear deck was not cut out under the grilles, but indented to accept the grilles which were merely decorative. My Chevrolet service manuals for the years '74 & '75 indicate that the A/C models did not need (nor have) any of the innards of the rear Astrovent system. That cost offset was more than surpassed by the A/C, I'm sure. I hope I didn't make this any worse for anyone. Thanks!
Sorry if I was confusing. Astrovent cars had the plenum set-up with vacuum actuated doors, grilles to the outside, and drains. My '75 with A/C didn't have Astrovent and consequently didn't use a plenum that I ever saw. The rear deck was not cut out under the grilles, but indented to accept the grilles which were merely decorative. My Chevrolet service manuals for the years '74 & '75 indicate that the A/C models did not need (nor have) any of the innards of the rear Astrovent system. That cost offset was more than surpassed by the A/C, I'm sure. I hope I didn't make this any worse for anyone. Thanks!
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Hi, Alan!
Sorry if I was confusing. Astrovent cars had the plenum set-up with vacuum actuated doors, grilles to the outside, and drains. My '75 with A/C didn't have Astrovent and consequently didn't use a plenum that I ever saw. The rear deck was not cut out under the grilles, but indented to accept the grilles which were merely decorative. My Chevrolet service manuals for the years '74 & '75 indicate that the A/C models did not need (nor have) any of the innards of the rear Astrovent system. That cost offset was more than surpassed by the A/C, I'm sure. I hope I didn't make this any worse for anyone. Thanks!
Sorry if I was confusing. Astrovent cars had the plenum set-up with vacuum actuated doors, grilles to the outside, and drains. My '75 with A/C didn't have Astrovent and consequently didn't use a plenum that I ever saw. The rear deck was not cut out under the grilles, but indented to accept the grilles which were merely decorative. My Chevrolet service manuals for the years '74 & '75 indicate that the A/C models did not need (nor have) any of the innards of the rear Astrovent system. That cost offset was more than surpassed by the A/C, I'm sure. I hope I didn't make this any worse for anyone. Thanks!
Also theres is always a drop or two of water that hides under the tail lights until I take the ride and towel that off to.
Enjoy the weekend! PG.
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St. Jude Donor '08-'09-'10-'11