Deleteing '76 A/C
Racer
Joined: Apr 2006
Posts: 417
Likes: 0
From: Tacoma Washington
seventysixvette: I've just removed the air system but left the left side of the big *** box still in there since it has the heater motor in it. I would like to still have a heater though. Do you have a link to a smaller heater box that can be installed? I think you mentioned it earlier about getting one. I'd appreciate the info when you find/fab one. I'll post some pics of what I'm talking about. Maybe you guys have some ideas to help.
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 845
Likes: 1
From: Columbus Indiana
I've been working on a few other items, but I've found out a couple things. I bought a heater only outer box off e-bay. This has the motor, but is a lot smaller/thinner than the evaporater box. A little research showed a heater only box from '72 to '77 will interchange. Mine was off a '74 and is dated as such. It's what my '76 would have had stock.
The hole in the firewall is about an inch too big around the heater core end.
After pulling the motor/evaporater box off my firewall, the first thing I noticed was the heater only box is not only thinner, but is smaller. The large intake hole for the squirrel cage fan lines up, and the 2 mounting holes by the motor is fine. But when you mount the box on the firewall, there is a gap around the box of about an inch. This will be easily fixed with a little sheet aluminum.
The second thing I've ran into is finding the inner half of a heater only system in the years I need one.
I still might end up sawing my evaporater box up (I'll take the evaporater part off and make the whole thing thinner), then ripping out all the vacuum valving and flapper doors out of the passengers compartment half and using it for the heater/defroster only. I'll post pics of what I'm trying to describe later today.
(Pic is worth a thousand words, especially when it's me writing.)
John
The hole in the firewall is about an inch too big around the heater core end.
After pulling the motor/evaporater box off my firewall, the first thing I noticed was the heater only box is not only thinner, but is smaller. The large intake hole for the squirrel cage fan lines up, and the 2 mounting holes by the motor is fine. But when you mount the box on the firewall, there is a gap around the box of about an inch. This will be easily fixed with a little sheet aluminum.
The second thing I've ran into is finding the inner half of a heater only system in the years I need one.
I still might end up sawing my evaporater box up (I'll take the evaporater part off and make the whole thing thinner), then ripping out all the vacuum valving and flapper doors out of the passengers compartment half and using it for the heater/defroster only. I'll post pics of what I'm trying to describe later today.
(Pic is worth a thousand words, especially when it's me writing.)
John
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 845
Likes: 1
From: Columbus Indiana
Pics!
Here are the pics I promised....
This is a comparison between the heater only outer box, and the heater-A/C evaporater box. There's a lot of room taken up by the evaporater sticking out.
Here you can see how much of a gap is created by the heater core end of the box being smaller than the evaporater. The fan and mounting studs on the motor end line up fine. There's just about a 1" gap on the bottom and where the core inlet and outlet tubes are.
If worse comes to worse and I just can't come up with an inner box, I'll leave the two halves of the evaporater box bolted together, and cut somewhere along the dotted line I've drawn. I'll make a fiberglass patch, and use this in the engine compartment to mate up with the modified A/C inner box I'll have to use.
You wouldn't think a 'simple' delete would be so hard...
John
This is a comparison between the heater only outer box, and the heater-A/C evaporater box. There's a lot of room taken up by the evaporater sticking out.
Here you can see how much of a gap is created by the heater core end of the box being smaller than the evaporater. The fan and mounting studs on the motor end line up fine. There's just about a 1" gap on the bottom and where the core inlet and outlet tubes are.
If worse comes to worse and I just can't come up with an inner box, I'll leave the two halves of the evaporater box bolted together, and cut somewhere along the dotted line I've drawn. I'll make a fiberglass patch, and use this in the engine compartment to mate up with the modified A/C inner box I'll have to use.
You wouldn't think a 'simple' delete would be so hard...
John
Drifting
Joined: Oct 2003
Posts: 1,426
Likes: 1
From: VetteMOD
St. Jude Donor '05-'07
I had to enlarge the hole going from non AC to AC so I had the opposite problem. If you are going to keep the original plenum inside the car (the AC plenum), I would cut your old evaporator box as you have shown. If you are converting your plenum inside to non-AC, I would cut a piece from fiberglass sheet and fill the gaps. I still have the pieces I cut out. I would be happy to make a template from them and send it to you.
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 845
Likes: 1
From: Columbus Indiana
Originally Posted by BBShark
I had to enlarge the hole going from non AC to AC so I had the opposite problem. If you are going to keep the original plenum inside the car (the AC plenum), I would cut your old evaporator box as you have shown. If you are converting your plenum inside to non-AC, I would cut a piece from fiberglass sheet and fill the gaps. I still have the pieces I cut out. I would be happy to make a template from them and send it to you.
John
