Rear plenum drain detail
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,249
From: Westminster Maryland
Hi Dwight,
Here's a link to a thread that has a good picture of the left-side plunum and drain hose in a convertible.
Perhaps it'll show you what you need to know.
Regards,
Alan
Post #18 has a good photo.
https://www.corvetteforum.com/forums...ntilation.html
Here's a link to a thread that has a good picture of the left-side plunum and drain hose in a convertible.
Perhaps it'll show you what you need to know.
Regards,
Alan
Post #18 has a good photo.
https://www.corvetteforum.com/forums...ntilation.html
Last edited by Alan 71; Feb 1, 2017 at 06:14 PM.
Thread Starter
Intermediate
Joined: Dec 2014
Posts: 38
Likes: 2
Hi Dwight,
Here's a link to a thread that has a good picture of the left-side plunum and drain hose in a convertible.
Perhaps it'll show you what you need to know.
Regards,
Alan
Post #18 has a good photo.
https://www.corvetteforum.com/forums...ntilation.html
Here's a link to a thread that has a good picture of the left-side plunum and drain hose in a convertible.
Perhaps it'll show you what you need to know.
Regards,
Alan
Post #18 has a good photo.
https://www.corvetteforum.com/forums...ntilation.html
Thanks Alan. I don't know if the model year changes but the plenum is behind the divider panel of the luggage compartment and the underside of the car. Any ideas on that?
Thanks for your help.
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,249
From: Westminster Maryland
Hi DGK,
In the drawing I posted items #1 & 2 are on the 'outside' of the underbody… they face the front of the gas tank.
Here's the photo I linked to in my previous post. It's the plenum area on a convertible.
The photo shows the fiberglass plenum, the rubber drain hose to the rear panel on the underbody, and the LOCATION of the 'flapper door' on cars with out a/c, OR, the block-off plate on cars with a/c.
Was your car originally built with the a/c option?…. that will determine what you see inside the car as I described above.
Regards,
Alan
In the drawing I posted items #1 & 2 are on the 'outside' of the underbody… they face the front of the gas tank.
Here's the photo I linked to in my previous post. It's the plenum area on a convertible.
The photo shows the fiberglass plenum, the rubber drain hose to the rear panel on the underbody, and the LOCATION of the 'flapper door' on cars with out a/c, OR, the block-off plate on cars with a/c.
Was your car originally built with the a/c option?…. that will determine what you see inside the car as I described above.
Regards,
Alan
Last edited by Alan 71; Feb 2, 2017 at 08:41 AM.
Thread Starter
Intermediate
Joined: Dec 2014
Posts: 38
Likes: 2
Hi DGK,
In the drawing I posted items #1 & 2 are on the 'outside' of the underbody… they face the front of the gas tank.
Here's the photo I linked to in my previous post. It's the plenum area on a convertible.
The photo shows the fiberglass plenum, the rubber drain hose to the rear panel on the underbody, and the LOCATION of the 'flapper door' on cars with out a/c, OR, the block-off plate on cars with a/c.
Was your car originally built with the a/c option?…. that will determine what you see inside the car as I described above.
Regards,
Alan
In the drawing I posted items #1 & 2 are on the 'outside' of the underbody… they face the front of the gas tank.
Here's the photo I linked to in my previous post. It's the plenum area on a convertible.
The photo shows the fiberglass plenum, the rubber drain hose to the rear panel on the underbody, and the LOCATION of the 'flapper door' on cars with out a/c, OR, the block-off plate on cars with a/c.
Was your car originally built with the a/c option?…. that will determine what you see inside the car as I described above.
Regards,
Alan
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Le Mans Master
Joined: Nov 2004
Posts: 5,251
Likes: 766
From: Waterford WI
I'm hesitant to disagree with Alan, because his knowledge far surpasses mine. But I believe that because of the reconfiguration of the rear bulkhead between 70 and 71 (and your 72 is similar to 71) that what you have is correct. The illustration Alan shared is from the 1970 AIM. It is not in the 71 or 72 AIM, and I understand that's because the bulkhead was moved slightly forward for 1971. Thus the plenum under the rear grilles simply dumps between the bulkhead and the tank directly to the ground, with no ductwork as shown in the 70 AIM. You can check pages 1 F 22 and 1 F 24 in the respective AIMs.
Mike
Mike
Last edited by 62corvette; Feb 2, 2017 at 04:35 PM. Reason: Fat fingers
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,249
From: Westminster Maryland
Hi Mike,
You're right!
Now that you've mentioned it I remember that.
So... the info I posted is really only for 70 cars.
I'll alert Dwight with a PM so for sure he sees your post!
Thanks for covering my butt!
I'm really dismayed at the mix up I've caused!
Regards,
Alan
I remember now reading the people with convertibles reported that they could see the ground under their car when they looked through the outer ends of the rear deck grills…they were looking through the drain holes!!!!
You're right!
Now that you've mentioned it I remember that.
So... the info I posted is really only for 70 cars.
I'll alert Dwight with a PM so for sure he sees your post!
Thanks for covering my butt!
I'm really dismayed at the mix up I've caused!
Regards,
Alan
I remember now reading the people with convertibles reported that they could see the ground under their car when they looked through the outer ends of the rear deck grills…they were looking through the drain holes!!!!
Last edited by Alan 71; Feb 2, 2017 at 05:05 PM.
Le Mans Master
Joined: Nov 2004
Posts: 5,251
Likes: 766
From: Waterford WI
Alan,
No problem! I've been owning, studying, and restoring 62s since 1974. I've owned 28 of them, and several I bought because of options or early car vs. late car, and I still screw up on them!
Mike
No problem! I've been owning, studying, and restoring 62s since 1974. I've owned 28 of them, and several I bought because of options or early car vs. late car, and I still screw up on them!
Mike
Thread Starter
Intermediate
Joined: Dec 2014
Posts: 38
Likes: 2
Thank you both for helping figure this out. After Alan's last post I referenced another source and came up with the fact that the back divider was relocated on the 72 and that the plenum just had a hole in the bottom. Mike thanks for confirming that.
Regards,
Dwight
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,249
From: Westminster Maryland
Hi Mike,
28 cars!
My problem is quite the opposite… my experience is limited to just one car, (46 years), and I get into trouble thinking too often that 1970 cars and 1972 cars are just like what I have sitting in front of me!
Thanks again for having the right information!
Regards,
Alan
28 cars!
My problem is quite the opposite… my experience is limited to just one car, (46 years), and I get into trouble thinking too often that 1970 cars and 1972 cars are just like what I have sitting in front of me!
Thanks again for having the right information!
Regards,
Alan
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
I'm hesitant to disagree with Alan, because his knowledge far surpasses mine. But I believe that because of the reconfiguration of the rear bulkhead between 70 and 71 (and your 72 is similar to 71) that what you have is correct. The illustration Alan shared is from the 1970 AIM. It is not in the 71 or 72 AIM, and I understand that's because the bulkhead was moved slightly forward for 1971. Thus the plenum under the rear grilles simply dumps between the bulkhead and the tank directly to the ground, with no ductwork as shown in the 70 AIM. You can check pages 1 F 22 and 1 F 24 in the respective AIMs.
Mike
Mike
