Suburban A/C fix + Vintage Air? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

swissarmychainsaw · 06-02-2018, 11:53 AM

Hey all. I have a 1976 GMC Suburban, with a 6.0 LS2 (carb'd) out of a trailblazer ss. (bought it this way).

My cab has factory (front-only) A/C and it seems that all the stock parts are there except for the compressor and lines.

How feasible is this:
Uses all the stock components for the front A/C.
Add the LS appropriate compressor/bracket.
Use Factory switches (so the temp control etc. is stock)

Somehow Tee off this and add a Vintage Air for the rear, and make that switched so you could run them independently.

I have read that some guys have done this with a mini/slimline.

Is fairly doable? I honestly know NOTHING about A/C and have been reading up on it.
It seems like a fairly straight forward project (hahaha).

Nick

68Timber · 06-03-2018, 08:02 AM

The slim line unit, you would still mount this overhead in the rear? I've read that the new aftermarket ac packages blow much colder and are a big improvement over original OEM units. But for purposes of retrofitting AC into the back of a Suburban, if aesthetics matter, it's going to be hard to beat using the original OEM pieces. Probably a lot cheaper too, if you buy a parts truck that has what you need. I'm not against aftermarket AC at all, just thinking out loud here.

swissarmychainsaw · 06-03-2018, 11:46 AM

I'm definitely open to using original stuff.
It's a matter of finding a donor, then getting it all to work, and I'm no A/C guru.
I agree the stock units look much better, but right not ordering new stuff and installing it is enough of a project! :-)

68Timber · 06-03-2018, 12:52 PM

I'm no AC expert either but I did replace the compressor and drier on our old Yukon a few years ago after watching a few youtube videos. Think of it all as a hydraulic system that produces lower temps instead of line pressure for a ram. It's all plug and play and the only real problem is the potential for leaks. Use the force and you'll be fine. I'm not trying to oversimplify, but really there's no magic going on here. Once it's all bolted on and buttoned up, you need someone to pull a vacuum on the system and charge it for you, but you'll need to do that either way. Also need to read up on converting freon to R134a and use the parts needed to convert. You might need custom lines made to hook up the factory system to the newer LS compressor, but I think I read somewhere here that there's an existing set of OEM lines that fit. I have since fixed the rear AC on the Yukon since the compressor was replaced. Once you burst the mystique bubble, it's just car parts. If I can do it, any shade-tree can.

swissarmychainsaw · 06-03-2018, 10:37 PM

You are welcome to come visit and lend a hand! I'll buy the beer!

I just found a donor (3 actually - this guy has more Suburbans than I do!).
He's asking $250 for "everything" for the rear A/C.

I figure I'll give that a shot. Going to get it this week.

68Timber · 06-03-2018, 11:11 PM

No kidding, you can do it. Donor truck really makes it simple, when you have to take it off, you're well versed in how it goes on.

68Timber · 06-06-2018, 11:39 AM

I used ac specific o-rings. I was replacing bad parts that came with new o-rings.

swissarmychainsaw · 06-06-2018, 01:30 PM

So are we going with R-12 or R-134a?

I'm putting together a shopping list, as an update I have:
2008 6.0 LS2 Trailblazer SS engine (no AC currently) Carburated.
1976 Body, with Front AC only
Adding Rear AC Donor was an 1986 Suburban

Shopping List
1. AC O-ring kit
2. Oil for o-rings (PAG for R134?)
3. Compressor (from the Trailblazer)
4. A/C Receiver Drier / Accumulator Should come with new compressor
5. High mount bracket for compressor
6. A/C Refrigerant Hose ( for rear AC )
7. Condenser (Radiator 1986)

Going to add some kind of insulation on the roof under the headliner.
Not sure what to use yet. Might just go with cheap Aluminum bubble wrap from Home depot gluing it on with 3M spray 90 adhesive (using this for the headliner also).

I guess I need a way to connect the 1976 Controls to the new 2008 Compressor.
No idea how to do that yet.

swissarmychainsaw · 06-06-2018, 06:17 PM

Today I removed the rear headliner (which is sagging badly)
Also, it had some water stains on it. Maan, it's tempting to give in to "shipwrights disease" and start fixing everything
I find.

I was shocked to see that the roof rack is only tied into the outer roof skin and not the cross members!
I have a plan to add a beefy roof rack, using the existing mounting holes.

I needed to drill some holes, but got the AC unit hung (test fit)

Need to cut a hole here for the hoses

I assume both of these should have O-rings right?

This one fell out

I think it goes here

swissarmychainsaw · 06-06-2018, 09:26 PM

I hate to cut sheetmetal, but here we go:

Test fitting the manifold:

Manifold Cover - Note the original screws go nowhere on this, I'll have to fab up a bracket for this and the overhead cover:

Oh, and here is a shot of the underside of the Original Headliner on my Burb.
Definitely had some water in there. My son said it "looks like Art!"

Hubscrub · 06-07-2018, 09:31 PM

I'm following this I'm gonna work on my 91 burbs air soon. Nice work so far.

swissarmychainsaw · 06-11-2018, 02:01 PM

Work on the AC headliner (which is different than the non/AC one):

Used three methods to scrape the old foam backing off the cardboard.

Then I used 3M 90 Spray Adhesive from Home depot

The bubbles were disappointing as hell, but it looked a little better in the morning.
This was the old headliner (all the foam backing had deteriorated), and I had read that using the old stuff does not work well, as the foam helps make the final cloth look very uniform.

So if you try this at home, us NEW headliner material. I'm going to see if I can buff it out a bit and use it as is for now...

But man I was sad last night!

swissarmychainsaw · 06-11-2018, 09:36 PM

Is this thing on?

I have watched some videos on this and it seems *really* straight forward to charge the system.

Things I need to sort out:
How to turn on the compressor, do I have the stock plug on my truck to do this?
Rig up a switch for the rear fan

I bought an O-ring kit and oil, and some system flush to clean out my junkyard parts and get them together.

In other news, I dropped coin on the Holley adapter and Sanden pump kit.

I know there might be a cheaper way to do this, but my time is somewhat limited and a "plug and play" kit, where everything lines up correctly is just the ticket:

swissarmychainsaw · 06-12-2018, 10:36 AM

Anyone have a picture of their suburban's ac lines and hoses, the under hood view?

I need a pic of what it's supposed to look like when I'm done!

Thanks!

SCOTI · 06-12-2018, 03:10 PM

Did your used-parts source not have anything you could look at?

swissarmychainsaw · 06-12-2018, 07:24 PM

Quote:

Originally Posted by SCOTI

Did your used-parts source not have anything you could look at?

My parts guy is just a dude about 1.5 hours away that is parting some 80s squares. Most of his stuff was not very complete, and when I was there we did not have much time so I was focused on getting the rear a/c and lines from under the truck. The whole front clip, motor and lines were gone from that one.

I have a manual I can look at, not a big deal.

I also found this, which inspired me to (spend more money...cough) err do it myself:
https://youtu.be/Pdq8JAlct6s

Irish1941 · 06-13-2018, 01:09 AM

A little late to the party but it aint that hard. LS carb'd is odd but in your favor with no ECM input for the ac & fuel system. Shame all that EFI engineering is gone.
Anyway this diagram may help you out with your lines.

swissarmychainsaw · 06-13-2018, 11:53 AM

Quote:

Originally Posted by Irish1941

A little late to the party but it aint that hard. LS carb'd is odd but in your favor with no ECM input for the ac & fuel system. Shame all that EFI engineering is gone.
Anyway this diagram may help you out with your lines.

Thanks a ton! Can you post the part where it shows the labels?
The wiring is the part I really need!

I would prefer to have the stock FI for sure, but I sort of get why some folks use Carbs: it's relatively simple, especially if you "get" carbs.
My Holley is not yet running to its full potential, but I'm getting there.

Thanks again for the diagram!

swissarmychainsaw · 06-15-2018, 10:32 AM

In other news:

Parts from Summit came in:

Found Duct Insulation at the Hardware store and thought I'd try it.

**hatzie** · 06-15-2018, 11:45 AM

The wiring diagrams are in the manuals thread. You'll find the rear AC wiring separated from the main harness diagram.

Hubscrub · 06-15-2018, 10:42 PM

That insulation looks like a good idea.

**hatzie** · 06-16-2018, 08:34 AM

Rear AC Wiring Diagram

Rear window wiring diagram.

swissarmychainsaw · 06-16-2018, 04:24 PM

Quote:

Originally Posted by hatzie

Rear AC Wiring Diagram
Rear window wiring diagram.

This is awesome, I also noticed your "fundamentals of air conditioning" link!
Thanks a ton for making all that available!

catch2otwo · 07-08-2018, 05:59 PM

hey hey, noticed you were a fellow east bayer, care to share you parts guy? About to start restoring my wifes 73. Also plan on rear ac.

swissarmychainsaw · 07-11-2018, 12:27 PM

Quote:

Originally Posted by catch2otwo

hey hey, noticed you were a fellow east bayer, care to share you parts guy? About to start restoring my wifes 73. Also plan on rear ac.

PM Sent!

06-02-2018, 11:53 AM	#1
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Suburban A/C fix + add rear air Hey all. I have a 1976 GMC Suburban, with a 6.0 LS2 (carb'd) out of a trailblazer ss. (bought it this way). My cab has factory (front-only) A/C and it seems that all the stock parts are there except for the compressor and lines. How feasible is this: Uses all the stock components for the front A/C. Add the LS appropriate compressor/bracket. Use Factory switches (so the temp control etc. is stock) Somehow Tee off this and add a Vintage Air for the rear, and make that switched so you could run them independently. I have read that some guys have done this with a mini/slimline. Is fairly doable? I honestly know NOTHING about A/C and have been reading up on it. It seems like a fairly straight forward project (hahaha). Nick Last edited by swissarmychainsaw; 06-06-2018 at 09:28 PM. Reason: Changed Title to something more fitting

06-03-2018, 08:02 AM	#2
68Timber I know the pieces fit Join Date: Nov 2007 Location: MONTGOMERY, AL Posts: 5,523	Re: Suburban A/C fix + Vintage Air? The slim line unit, you would still mount this overhead in the rear? I've read that the new aftermarket ac packages blow much colder and are a big improvement over original OEM units. But for purposes of retrofitting AC into the back of a Suburban, if aesthetics matter, it's going to be hard to beat using the original OEM pieces. Probably a lot cheaper too, if you buy a parts truck that has what you need. I'm not against aftermarket AC at all, just thinking out loud here. __________________ John 79 2wd Blazer (Bruiser) 85 M1009 Blazer (Sarge) build 74 Honda Z50 build

06-03-2018, 11:46 AM	#3
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? I'm definitely open to using original stuff. It's a matter of finding a donor, then getting it all to work, and I'm no A/C guru. I agree the stock units look much better, but right not ordering new stuff and installing it is enough of a project! :-)

06-03-2018, 12:52 PM	#4
68Timber I know the pieces fit Join Date: Nov 2007 Location: MONTGOMERY, AL Posts: 5,523	Re: Suburban A/C fix + Vintage Air? I'm no AC expert either but I did replace the compressor and drier on our old Yukon a few years ago after watching a few youtube videos. Think of it all as a hydraulic system that produces lower temps instead of line pressure for a ram. It's all plug and play and the only real problem is the potential for leaks. Use the force and you'll be fine. I'm not trying to oversimplify, but really there's no magic going on here. Once it's all bolted on and buttoned up, you need someone to pull a vacuum on the system and charge it for you, but you'll need to do that either way. Also need to read up on converting freon to R134a and use the parts needed to convert. You might need custom lines made to hook up the factory system to the newer LS compressor, but I think I read somewhere here that there's an existing set of OEM lines that fit. I have since fixed the rear AC on the Yukon since the compressor was replaced. Once you burst the mystique bubble, it's just car parts. If I can do it, any shade-tree can. __________________ John 79 2wd Blazer (Bruiser) 85 M1009 Blazer (Sarge) build 74 Honda Z50 build

06-03-2018, 10:37 PM	#5
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? You are welcome to come visit and lend a hand! I'll buy the beer! I just found a donor (3 actually - this guy has more Suburbans than I do!). He's asking $250 for "everything" for the rear A/C. I figure I'll give that a shot. Going to get it this week.

06-03-2018, 11:11 PM	#6
68Timber I know the pieces fit Join Date: Nov 2007 Location: MONTGOMERY, AL Posts: 5,523	Re: Suburban A/C fix + Vintage Air? No kidding, you can do it. Donor truck really makes it simple, when you have to take it off, you're well versed in how it goes on. __________________ John 79 2wd Blazer (Bruiser) 85 M1009 Blazer (Sarge) build 74 Honda Z50 build

06-06-2018, 11:39 AM	#7
68Timber I know the pieces fit Join Date: Nov 2007 Location: MONTGOMERY, AL Posts: 5,523	Re: Suburban A/C fix + Vintage Air? I used ac specific o-rings. I was replacing bad parts that came with new o-rings. __________________ John 79 2wd Blazer (Bruiser) 85 M1009 Blazer (Sarge) build 74 Honda Z50 build

06-06-2018, 01:30 PM	#8
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? So are we going with R-12 or R-134a? I'm putting together a shopping list, as an update I have: 2008 6.0 LS2 Trailblazer SS engine (no AC currently) Carburated. 1976 Body, with Front AC only Adding Rear AC Donor was an 1986 Suburban Shopping List 1. AC O-ring kit 2. Oil for o-rings (PAG for R134?) 3. Compressor (from the Trailblazer) 4. A/C Receiver Drier / Accumulator Should come with new compressor 5. High mount bracket for compressor 6. A/C Refrigerant Hose ( for rear AC ) 7. Condenser (Radiator 1986) Going to add some kind of insulation on the roof under the headliner. Not sure what to use yet. Might just go with cheap Aluminum bubble wrap from Home depot gluing it on with 3M spray 90 adhesive (using this for the headliner also). I guess I need a way to connect the 1976 Controls to the new 2008 Compressor. No idea how to do that yet. Last edited by swissarmychainsaw; 06-06-2018 at 01:52 PM.

06-06-2018, 06:17 PM	#9
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? Today I removed the rear headliner (which is sagging badly) Also, it had some water stains on it. Maan, it's tempting to give in to "shipwrights disease" and start fixing everything I find. I was shocked to see that the roof rack is only tied into the outer roof skin and not the cross members! I have a plan to add a beefy roof rack, using the existing mounting holes. I needed to drill some holes, but got the AC unit hung (test fit) Need to cut a hole here for the hoses I assume both of these should have O-rings right? This one fell out I think it goes here Last edited by swissarmychainsaw; 06-06-2018 at 06:38 PM.

06-06-2018, 09:26 PM	#10
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? I hate to cut sheetmetal, but here we go: Test fitting the manifold: Manifold Cover - Note the original screws go nowhere on this, I'll have to fab up a bracket for this and the overhead cover: Oh, and here is a shot of the underside of the Original Headliner on my Burb. Definitely had some water in there. My son said it "looks like Art!"

06-07-2018, 09:31 PM	#11
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Re: Suburban A/C fix + Vintage Air? I'm following this I'm gonna work on my 91 burbs air soon. Nice work so far. __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

06-11-2018, 02:01 PM	#12
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? Work on the AC headliner (which is different than the non/AC one): Used three methods to scrape the old foam backing off the cardboard. Then I used 3M 90 Spray Adhesive from Home depot The bubbles were disappointing as hell, but it looked a little better in the morning. This was the old headliner (all the foam backing had deteriorated), and I had read that using the old stuff does not work well, as the foam helps make the final cloth look very uniform. So if you try this at home, us NEW headliner material. I'm going to see if I can buff it out a bit and use it as is for now... But man I was sad last night!

06-11-2018, 09:36 PM	#13
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? Is this thing on? I have watched some videos on this and it seems really straight forward to charge the system. Things I need to sort out: How to turn on the compressor, do I have the stock plug on my truck to do this? Rig up a switch for the rear fan I bought an O-ring kit and oil, and some system flush to clean out my junkyard parts and get them together. In other news, I dropped coin on the Holley adapter and Sanden pump kit. I know there might be a cheaper way to do this, but my time is somewhat limited and a "plug and play" kit, where everything lines up correctly is just the ticket:

06-12-2018, 10:36 AM	#14
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? Anyone have a picture of their suburban's ac lines and hoses, the under hood view? I need a pic of what it's supposed to look like when I'm done! Thanks!

06-12-2018, 03:10 PM	#15
SCOTI Registered User Join Date: Apr 2001 Location: DALLAS,TX Posts: 22,026	Re: Suburban A/C fix + Vintage Air? Did your used-parts source not have anything you could look at? __________________ 67SWB-B.B.RetroRod 64SWB-Recycle 89CCDually-Driver/Tow Truck 99CCSWB Driver All Fleetsides @rattlecankustoms in IG Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive. It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar..... *Cubic inches is like Indiana Jones with a cheap pistol.*



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06-13-2018, 01:09 AM	#17
Irish1941 Registered User Join Date: Nov 2012 Location: Los Angeles, CA Posts: 450	Re: Suburban A/C fix + Vintage Air? A little late to the party but it aint that hard. LS carb'd is odd but in your favor with no ECM input for the ac & fuel system. Shame all that EFI engineering is gone. Anyway this diagram may help you out with your lines.

06-15-2018, 10:32 AM	#19
swissarmychainsaw Registered User Join Date: Jun 2009 Location: san francisco, ca (east bay) Posts: 674	Re: Suburban A/C fix + Vintage Air? In other news: Parts from Summit came in: Found Duct Insulation at the Hardware store and thought I'd try it.

06-15-2018, 11:45 AM	#20
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 4,975	Re: Suburban A/C fix + Vintage Air? The wiring diagrams are in the manuals thread. You'll find the rear AC wiring separated from the main harness diagram. __________________ 1959 M35A2 LDT465-1D SOLD 1967 Dodge W200 B383, NP420/NP201 SOLD 1969 Dodge Polara 500 B383, A833 SOLD 1972 Ford F250 FE390, NP435/NP205 SOLD 1976 Chevy K20, 6.5L, NV4500/NP208 SOLD 1986 M1008 CUCV SOLD 2000 GMC C2500, TD6.5L, NV4500 2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263 2009 Impala SS LS4 V8 RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials... 1973-1991 GM Light Truck Service, Unit/Overhaul, Wiring Manuals, Parts Books and Some 1968-1999 GM Service Training textbooks in PDF 1988-1998 GMT400 CK service manual project 1988-1993 GMT400 CK parts books. 1967-1972 GM Light, Medium, & Heavy Truck Service Manuals in PDF Please include at least the year and model in your threads. It'll be easier to answer your questions. And please let us know if and how your repairs were successful.

06-15-2018, 10:42 PM	#21
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Re: Suburban A/C fix + Vintage Air? That insulation looks like a good idea. __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

06-16-2018, 08:34 AM	#22
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 4,975	Re: Suburban A/C fix + Vintage Air? Rear AC Wiring Diagram Rear window wiring diagram. __________________ 1959 M35A2 LDT465-1D SOLD 1967 Dodge W200 B383, NP420/NP201 SOLD 1969 Dodge Polara 500 B383, A833 SOLD 1972 Ford F250 FE390, NP435/NP205 SOLD 1976 Chevy K20, 6.5L, NV4500/NP208 SOLD 1986 M1008 CUCV SOLD 2000 GMC C2500, TD6.5L, NV4500 2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263 2009 Impala SS LS4 V8 RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials... 1973-1991 GM Light Truck Service, Unit/Overhaul, Wiring Manuals, Parts Books and Some 1968-1999 GM Service Training textbooks in PDF 1988-1998 GMT400 CK service manual project 1988-1993 GMT400 CK parts books. 1967-1972 GM Light, Medium, & Heavy Truck Service Manuals in PDF Please include at least the year and model in your threads. It'll be easier to answer your questions. And please let us know if and how your repairs were successful.

07-08-2018, 05:59 PM	#24
catch2otwo Registered User Join Date: Mar 2013 Location: SF Posts: 347	Re: Suburban A/C fix + Vintage Air? hey hey, noticed you were a fellow east bayer, care to share you parts guy? About to start restoring my wifes 73. Also plan on rear ac.

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