Put A/C Back in a 76?

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carguytroy

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Troy
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1976
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C20 Camper Special
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454
Our 76 C20 had A/C but the previous owner took out most all of the old components. I was at a local pick a part today grabbing some small trim items and started talking to a guy that said I should look for a system from a 91-93? I’m good with buying new parts just looking for a shopping list and a bit of direction. The motor is a 454 and I see the dryer and the front compressor bracket looks to be all that’s left. What’s the best way to put air back in the old tuck?
 

nabeshin

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400
Look up Vintage Air or Old Air Products.

They are both retrofit companies that can give you A/C. Neither has a cabin air filter, Old Air looses floor vents, both have new control panels.

I plan on going with Vintage Air.

Did I mention they are pricey?
 

bucket

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Look up Vintage Air or Old Air Products.

They are both retrofit companies that can give you A/C. Neither has a cabin air filter, Old Air looses floor vents, both have new control panels.

I plan on going with Vintage Air.

Did I mention they are pricey?

I was all about the Old Air Products setup, I thought it was a better looking setup. But damn, no floor vents? I never realized that. That's a no go for me. Glad I never spent the cash, lol.
 

nabeshin

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Yeah, I liked how Old Air could come with new vents and seemed to be a good unit you could disassemble to clean out. I emailed them to ask once I saw that the control unit only had Dash and Defrost settings.

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from their email back to me:

"Good morning, to simply answer your question no there is not a option for it to be one the floor only. We do have people that will take one duct hose and instead off routing it to a vent under the dash they will just route it straight up and facing it pointing down blowing to the floor to get more air flow to the floor. But there is not a setting to have it just blow in the footwell. And no it does not have a cabin filter and it cannot be added."


Vintage Air panel:
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Vintage Air also has infinite blower speeds unlike the Old Air one.
 

78C10BigTen

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Yeah, I liked how Old Air could come with new vents and seemed to be a good unit you could disassemble to clean out. I emailed them to ask once I saw that the control unit only had Dash and Defrost settings.

You must be registered for see images attach


from their email back to me:

"Good morning, to simply answer your question no there is not a option for it to be one the floor only. We do have people that will take one duct hose and instead off routing it to a vent under the dash they will just route it straight up and facing it pointing down blowing to the floor to get more air flow to the floor. But there is not a setting to have it just blow in the footwell. And no it does not have a cabin filter and it cannot be added."


Vintage Air panel:
You must be registered for see images attach

Vintage Air also has infinite blower speeds unlike the Old Air one.
Thats a terrible response! Sounds very much like a foreigner trying to speak english. I wouldnt trust that company just based on that email!
 

clendon1

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I have Vintage Air in my 76, has vents in all three places,cut the dash vents in the place where the factory dash vents would go, used the small storage box in the dash for one of the vents, nice clean installation, no box under dash to ruin the looks of the interior. A little pricey at around $1300 for the kit, but you get what you pay for, highly reccomend .
 

Snoots

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Our 76 C20 had A/C but the previous owner took out most all of the old components. I was at a local pick a part today grabbing some small trim items and started talking to a guy that said I should look for a system from a 91-93? I’m good with buying new parts just looking for a shopping list and a bit of direction. The motor is a 454 and I see the dryer and the front compressor bracket looks to be all that’s left. What’s the best way to put air back in the old tuck?

If it were me, I'd grab a '76 Service manual, probably listed on the GMSB front page, and go for the p/n's. That'll also help with the assembly. You can go with a boneyard compressor, condenser, hoses and evaporator from there. A NEW receiver/drier should be installed. Use NEW GREEN O-Rings.

No pix so I can't begin to say what all you need.
 

75gmck25

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I first tried to resurrect the missing A/C in my '75 with a rebuilt factory A6 compressor, but found out later that the A6 frequently suffers from "black death" and complete failure (which happened to the rebuilt unit). However, they now sell the Pro6Ten, which has the same form factor as the A6 (uses same brackets and hoses), but is really a Sanden in disguise. However, you may not want to track down all those A6 brackets if they are missing.

I'm currently using a Sanden compressor and brackets from Vintage Air, and had custom hoses made to connect it to the stock evaporator and aftermarket condenser. The rest of the system is still the stock GM parts. Its kind of a PIA to keep it all working right, since the nest of vacuum hoses and vacuum actuators under the dash sometimes go haywire, but the system does work well to heat and cool. I used R134a and PAG 100, new receiver/drier, green O-rings and a Ford Blue orifice, and charged it to about 75-80% of the R12 recommendation. YMMV.

I've currently got many of the underdash parts out because an $8 "diverter link" on one of the doors inside the plenum behind the dash is broken. Its the link to the vacuum actuator that moves the door between defrost and heat, so I'd like it to work properly. However, there were quite a few pieces to get out of the way before I could take out the one screw that holds the door link in place, and I'm waiting on lmctruck.com to mail out the new link. I hope it matches the old one.

You can pull the glove box door and the 3 screws that hold the plenum cover just behind it, and then you can see into the heater box. You may find a mouse nest and/or all the pens, match books, bolts and clips that have fallen into the defroster vents. At least one of those bolts is probably laying down and oriented so it keeps the heat/cold blend door from moving fully in both directions.

Bruce
 

RecklessWOT

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From what I hear the Vintage Air is the better setup of the two, but man I hate hate hate the way it looks, and just the idea of it in general. I would rather go through the hassle of sourcing original parts than slap some funky aftermarket A/C system in my truck
 

Craig 85

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My truck is a factory A/C truck. The rubber A/C lines were damaged and the A6 Compressor needed to be replaced along with other parts. I ended up going with a true Sanden compressor for reliability and save some weight. I have bought new or NOS parts to rebuild the otherwise stock system. It works great and the A/C blows at 40 degrees.

Based on what I've spent, it would almost the same cost and less frustration to go with the aftermarket system. I've had 2 aftermarket A/C systems back in the early to mid 90's. I never thought they heated or cooled as well as OEM systems and due to the fact the blower is inside the cab, it's a little louder. I would think, though, new systems have become more efficient than the systems I had. I have all the OEM BB brackets if you choose to go that route.

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Rusty Nail

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I will look very,very hard at a 100% FACTORY serpentine swap from a donor truck - + wire relay for electric fan and everything.
As a bonus to better compressor, you'd manage to pick up a few "free ponies" to boot!

Did I mention it would be cheap?
Parts-store availability is worth a TON of money.
I say that all the time here but

:waytogo:

This is in my bookmarks....I had a '75.

https://www.google.com/search?q=san...ved=0ahUKEwjVpNfyttzPAhVq6YMKHSRyAuQQ_AUIBCgA
 
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75gmck25

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This is how the Sanden and brackets from Vintage Air look when used to replace the A6 in my ‘75. If I had the right tools I might build new hoses and route them a little differently to get them out of the way more, but otherwise I like the setup. It still uses a long drive belt like the original A6, but it stays on fine.

Bruce

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75gmck25

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Here's a picture of my truck's engine in 2004 when the A6 was still installed. You can see the front bracket, but there is also a multi-piece support bracket on the back end. It runs across and bolts to the intake manifold, and has a piece that extends down and bolts to the exhaust manifold bolts. That bracket is built like a tank to hold that heavy compressor.

You can also see how the receiver/drier is a unique design that comes in two pieces (the curved part on the bottom is a separate piece). I used a drier from a newer truck ('85 I think) when I upgraded because it had two connections near the top of the drier.

The small A/C hose that runs across the big radiator hose near the bottom of the picture was also a problem. Its a small diameter hose, but has a large fitting on the evaporator end because the evaporator fitting is sized to fit over the expansion tube holder. A/C fitting manufacturers assume the hoses and fittings sizes match, so they don't make large diameter fittings for a a small diameter hose. We used a standard o-ring fitting on the condenser end, but at the evaporator they had to braze together two fittings to get the sizes to work. IIRC, the fitting on the evaporator is 3/4" (mates with #12 hose), but the hose to the condenser is #8 (1/2" fitting) or #10 (5/8" fitting).

Bruce

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