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-   -   Factory A/C, what to do (https://67-72chevytrucks.com/vboard/showthread.php?t=741606)

dmjlambert 07-03-2017 07:37 PM

Factory A/C, what to do
 
Folks, assume I know very little about A/C. I am able to understand mechanical things but an A/C novice and I have no tools related to A/C. What I have here is a 1969 CST/10 with A/C, and so far I have not done anything with the A/C. When I pulled the engine and fixed it up, I just unbolted the compressor and set it aside and left the hoses attached. The whole A/C system looks pretty much undisturbed although dirty, and the only things I see obviously wrong are the control panel has broken levers and the A/C clutch wire is chewed up, and the inside duct work has been re-routed in weird ways to accommodate a larger than stock radio.

So, here are my questions: Should I keep the hoses attached and fix and clean around the system assuming it is still pressurized? If I can get the controls, wiring, and blower motor and other such things working, I would then have the R-12 topped off and install a belt on the compressor and see what I get when I start it up. Would that be worth the trouble, or should I go ahead and completely disassemble right from the start?

B. W. 07-03-2017 09:44 PM

Re: Factory A/C, what to do
 
The system has probably leaked down over the years but, maybe not. If you have access to a set of gauges you can check for pressure. If you are going to do the work yourself you need a set of gauges anyway. Static pressure on a fully charged system should be around 80-100 psi. (someone here may have a more exact #) If it's low or at zero then go ahead & disassemble. If it's at, or close to full charge then leave it together & try it.

engineer_gregh 07-04-2017 09:32 AM

Re: Factory A/C, what to do
 
I just went through this with my truck. I did a lot of research before I started. Just a few things to consider; wear safety glasses as a shot of freon in the eyes can blind you, never open the high side gauge while recharging as the pressure from the compressor will feed back through the small can you're holding in your hand (dangerous), understand the difference in low pressure side and high pressure side, and its illegal to purge freon into the open air. Gauges are a must, you can get them from AutoZone as a loaner tool. YouTube has several videos on servicing A/C I found useful. There are lots of threads on this board to help in your decision to keep original or replace with Vintage Air.

Luvinit 07-04-2017 09:45 AM

Re: Factory A/C, what to do
 
Press in on one of the Schrader valves with a screw driver and you'll be able to tell if it still has any pressure. Then turn the front hub of the compressor by hand to see if it still turns this hub is connected to the pistons. More importantly figure out how the wiring functions and get the controls and cables working. An a/C mechanic can test and recharge the system. Good luck.

davepl 07-04-2017 01:17 PM

Re: Factory A/C, what to do
 
Presuming it's discharged and you want to get it ready for charging:

If you're going to do it yourself, you'll need the following:

Some kind of vacuum pump:
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Manifold Gauge Set:
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Then you get the system all set up, hook up the manifold gauges, run the vacuum pump to pull a full vacuum on the system, and see if it'll hold it overnight. If it does, then you go somewhere and get it charged up.

If not, you find and fix the leak, and repeat the process until it holds a vacuum overnight.

Since you'll have about $200 in tools to get that far, sometimes it's false economy doing it yourself and you should just take it somewhere that services AC. I wound up doing both, as my compressor leaked out the first fill I had... it only held vacuum for about 6 hours, which I convinced myself was "adequate", but it wasn't.

SJLenz1340 07-04-2017 01:46 PM

Re: Factory A/C, what to do
 
If your system is flat, then looking for leaks with a dry gas (nitrogen) under pressure is the best method. Do not use compressed air as the moisture level will cause you great pain. Leaks occur at all the usual places, compressor shaft, mechanical connections, and especially the evaporator since this is where dramatic changes in temperature occur. Get the system tight before evacuating or charging and you will be a happy camper.

kaycee 07-04-2017 01:57 PM

Re: Factory A/C, what to do
 
I did the same as you, I replaced all the vent tubes and such back to stock inside cab, traced all wires and hoses, brackets and got them hooked up and looking good for my taste. My compressor was good ,new drier and O-rings a 12 pack of bud light and off to my buddy's to recharge been holding good for a couple months now. He knew what oils and such to do so I'm not going to ask I am going to take him another 12 pack this afternoon .He did put 134 in though. I do live in Wyoming so the week we get into the 90/100 will be nice to have :lol:

dmjlambert 07-04-2017 02:15 PM

Re: Factory A/C, what to do
 
Thanks very much for all the information folks. This is the sort of thing I was hoping for in this post. If you vacuum and it leaks, how do you find the leak? Do you pressurize with air using some sort of pump?
EDIT I was writing while SJLenz1340 was writing. So where do you get nitrogen and is a pump required for that?

Steeveedee 07-08-2017 08:14 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by dmjlambert (Post 7983145)
Thanks very much for all the information folks. This is the sort of thing I was hoping for in this post. If you vacuum and it leaks, how do you find the leak? Do you pressurize with air using some sort of pump?
EDIT I was writing while SJLenz1340 was writing. So where do you get nitrogen and is a pump required for that?

You can get nitrogen from a welding supply, but you'll have to pay for the tank, since you don't have one. If you decide to do that, you can get a leak dye detector from an auto parts store. Just put some in - if you already evacuated it, then just take out the high side Schraeder valve and drip in the recommended amount. You could use oxygen, if you have that. The big deal is that you don't vent refrigerant into the air. Big trouble, if you get caught. BTW, the high side Schraeder valve is in the small AC line between the compressor and the condenser.

You won't need a pump, but you will need a regulator to reduce the pressure from the tank. You will then need an ultraviolet light to find where the leak is. #1 leak is from the front seal of the compressor. If you see an oil streak running across the underside of the hood, in line with your AC compressor clutch, it's the culprit.

Already Gone 07-08-2017 11:15 PM

Re: Factory A/C, what to do
 
Or, you can take it to a professional A/C shop and let them deal with it. Then you can enjoy nice A/C throughout the hot summer. I've done a lot of things to my trucks over the years and was reluctant to try them and oh so pround of myself after I did them and everything worked as it should. My feelings are there are lots of things we can do to our trucks but I like to leave what I call "specialty " work like trans rebuilds, engine overhauls and rear end and A/C work to the pros.

dmjlambert 07-08-2017 11:38 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by Already Gone (Post 7986571)
Or, you can take it to a professional A/C shop and let them deal with it. Then you can enjoy nice A/C throughout the hot summer. I've done a lot of things to my trucks over the years and was reluctant to try them and oh so pround of myself after I did them and everything worked as it should. My feelings are there are lots of things we can do to our trucks but I like to leave what I call "specialty " work like trans rebuilds, engine overhauls and rear end and A/C work to the pros.

Yes, I did exactly that with some things on the truck so far, such as my transmission and engine rebuilds. I will probably do some of the A/C dirty work such as cleaning, wiring, vacuum tubing, getting various bad parts replaced that are related to routing and blowing air, and the control panel, etc. Then for the closed refrigerant system, have a pro or a friend who is comfortable with it do that part.

dmjlambert 07-08-2017 11:43 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by Steeveedee (Post 7986423)
You can get nitrogen from a welding supply, but you'll have to pay for the tank, since you don't have one. If you decide to do that, you can get a leak dye detector from an auto parts store. Just put some in - if you already evacuated it, then just take out the high side Schraeder valve and drip in the recommended amount.

Thanks. I know somebody who does shade-tree mechanics for my newer vehicles, and he found and fixed some leaks on my Mazda Tribute using leak detector and ultraviolet light. He showed me some stuff. I think I will get him to help me with this.

clay68c10 07-08-2017 11:50 PM

Re: Factory A/C, what to do
 
Since you're wanting it to work correctly, go thru all the under dash stuff and fix/rebuild as necessary. It all gets worn out and it will work way better if you have all the ducting right.
I had a factory a/c truck when I lived in DFW and it was night and day after I repaired all the ducting. It's not too complicated or expensive.

hdff 07-09-2017 09:20 PM

Re: Factory A/C, what to do
 
1 Attachment(s)
There's a guy near you in ft. Worth that refurbishes and knows about old ac's. he refurbed mine and it looks great and has some great info. He goes by F A A Benny here on the forum and on Facebook..... look him up!

dmjlambert 07-09-2017 10:15 PM

Re: Factory A/C, what to do
 
That is a beautiful engine compartment. Did you leave it to him from beginning to end, drop off your truck and pick it up later with working A/C, or did you do some of the work yourself?

Steeveedee 07-09-2017 10:36 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by dmjlambert (Post 7986595)
Thanks. I know somebody who does shade-tree mechanics for my newer vehicles, and he found and fixed some leaks on my Mazda Tribute using leak detector and ultraviolet light. He showed me some stuff. I think I will get him to help me with this.

That would be better than dropping a pile of cash on the tank, regulator, etc. I only posted so that you would have an idea of what to do. It gets expensive fast. I have gauges and a vacuum pump because I bought an AC service machine from the shop I used to work at when the owner died.

Steeveedee 07-09-2017 11:02 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by hdff (Post 7987255)
There's a guy near you in ft. Worth that refurbishes and knows about old ac's. he refurbed mine and it looks great and has some great info. He goes by F A A Benny here on the forum and on Facebook..... look him up!

The under hood of my truck looks a mess, and I just don't really see why. I'm going to have to print this picture and do a "what is wrong with this picture" check on mine. Yours is a thing of real beauty! Of course, it's going to have to wait awhile. I had surgery on my left wrist (carpal tunnel) and it's hot enough to fry eggs on the sidewalk here in SoCal. It only got to 100 here today. :waah: I used to work in this heat, on cars and trucks. Those days are gone.

volksworld 07-10-2017 09:52 AM

Re: Factory A/C, what to do
 
a vacuum pump is also available from autozone as a loaner

jeffahart 07-10-2017 11:08 AM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by hdff (Post 7987255)
There's a guy near you in ft. Worth that refurbishes and knows about old ac's. he refurbed mine and it looks great and has some great info. He goes by F A A Benny here on the forum and on Facebook..... look him up!

Hey, how is your compressor wired? I noticed the two prongs are not connected.

hdff 07-10-2017 11:13 AM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by dmjlambert (Post 7987293)
That is a beautiful engine compartment. Did you leave it to him from beginning to end, drop off your truck and pick it up later with working A/C, or did you do some of the work yourself?

Thanks... I pulled the the evaporator/fan piece and the heater box and sent them to benny to be refurbished and checked because I live outside of Houston 4 hours from fort worth. He refurbed the boxes , checked and replaced the fan and evaporator, checked the expansion valve and poa, and knew of a place that could recore my original heater core. I installed it all including new hoses, condenser and rebuilt compressor. his work look great! everything went back together and looks great but I think the rebuilt compressor isn't working right so I need to check it out.

hdff 07-10-2017 11:21 AM

Re: Factory A/C, what to do
 
1 Attachment(s)
Quote:

Originally Posted by jeffahart (Post 7987538)
Hey, how is your compressor wired? I noticed the two prongs are not connected.

that pic was from when I got it all together but had not squirted the R12 in it yet so I had the compressor unplugged to prevent a ut-oh. heres another one during install to check the wire length

jeffahart 07-10-2017 11:45 AM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by hdff (Post 7987556)
that pic was from when I got it all together but had not squirted the R12 in it yet so I had the compressor unplugged to prevent a ut-oh. heres another one during install to check the wire length

Got ya. Hey, I don't think your compressor is bad. If you have not charged it yet. When you start charging and adding refrigerant, it will cycle once it gets enough refrigerant in there. Just make sure you got oil in there, if not, then you will fry the compressor.

Nice engine bay. Mine is uglier than me.... :lol:

hdff 07-10-2017 12:49 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by jeffahart (Post 7987577)
Got ya. Hey, I don't think your compressor is bad. If you have not charged it yet. When you start charging and adding refrigerant, it will cycle once it gets enough refrigerant in there. Just make sure you got oil in there, if not, then you will fry the compressor.

Nice engine bay. Mine is uglier than me.... :lol:

I added oil and Freon and it was only cooling down to ~55*, not nearly cold enough to make a difference in the 100*/ 95% humidity here on the gulf coast of texas. now the compressor is acting like it locks up and won't turn sometimes .......

jeffahart 07-10-2017 01:05 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by hdff (Post 7987618)
I added oil and Freon and it was only cooling down to ~55*, not nearly cold enough to make a difference in the 100*/ 95% humidity here on the gulf coast of texas. now the compressor is acting like it locks up and won't turn sometimes .......

Ya, after all that effort you want cold, especially if you used the r12. A loose belt will make you think the pulley is locking up, but it's the belt not gripping. Tighten the belt. I would seriously consider getting an evacuation and charge from a pro. I do my own, but I can hang with 50s, our heat here is pretty dry. Anything under 90 and I'm happy to just roll down the windows anyway. I am considering a proper oiling and evacuation from a good shop. I just replaced my compressor(and nothing else) with a dirt cheep A6 and did my own hokey evacuation and roughly speaking oiling, then charged with cheap wally world 134a (not sure if there is a quality difference in brands)... and I am getting low 50s at the vent. So, you should be able to do better for sure.

leddzepp 07-10-2017 01:19 PM

Re: Factory A/C, what to do
 
The a6 compressor does not cycle, it's either on or off.

The a6 will "lock up" and act like it's hard to turn, and your belt will squeal like a pig.

I went through 4 of them over the years on various trucks before I concluded I was wasting my time and went with a new aluminum a-10. No more belt squeals, no leaks, no problems. A rebuilt a-6 will fail, it's only a matter of time. They also leak at the front seal. I will never use one again unless it's the original one on the truck from the 70's and still functioning.

I restored the factory AC in my 68 a few weeks ago, a-10 compressor and r-12. 36 degree air idling at a stop light in 100 degree heat without missing a beat.

jeffahart 07-10-2017 01:39 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by leddzepp (Post 7987634)
The a6 compressor does not cycle, it's either on or off.

The a6 will "lock up" and act like it's hard to turn, and your belt will squeal like a pig.

I went through 4 of them over the years on various trucks before I concluded I was wasting my time and went with a new aluminum a-10. No more belt squeals, no leaks, no problems. A rebuilt a-6 will fail, it's only a matter of time. They also leak at the front seal. I will never use one again unless it's the original one on the truck from the 70's and still functioning.

I restored the factory AC in my 68 a few weeks ago, a-10 compressor and r-12. 36 degree air idling at a stop light in 100 degree heat without missing a beat.

I almost upgraded, cold instead of cool would be nice for sure. But decided to cheap out and go through the system when I pull the engine. I just got rid of the original A6. It was locking up and squealing like a stuck pig but was blowing pretty cold, it finally thew a belt. I put on my rebuilt junker and the compressor looked like it was locking up, like the old one... I blamed you and all your anti A6 posts.... :lol::lol: But I tightened the belt and it's been OK... but now that I said that it will probably spit oil next time I turn it on!! :uhmk:

leddzepp 07-10-2017 02:19 PM

Re: Factory A/C, what to do
 
:lol:

My pet peeve is non functioning or poor cooling AC. I run hot all the time and use it every time I drive a vehicle. It's one of the first things I learned to do myself because the first classic truck I owned I took to a shop and was charged $800 and got a converted 134 system that blew "lukewarm" air and a failed compressor within 2 months.

Already Gone 07-10-2017 03:24 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by leddzepp (Post 7987634)
The a6 compressor does not cycle, it's either on or off.

The a6 will "lock up" and act like it's hard to turn, and your belt will squeal like a pig.

I went through 4 of them over the years on various trucks before I concluded I was wasting my time and went with a new aluminum a-10. No more belt squeals, no leaks, no problems. A rebuilt a-6 will fail, it's only a matter of time. They also leak at the front seal. I will never use one again unless it's the original one on the truck from the 70's and still functioning.

I restored the factory AC in my 68 a few weeks ago, a-10 compressor and r-12. 36 degree air idling at a stop light in 100 degree heat without missing a beat.


Can you run R134 in an A-10.. I bought my truck with functioning A/C and discovered it has a rebuilt A-6 compressr and has been converted to 134...

weq92f 07-10-2017 04:17 PM

Re: Factory A/C, what to do
 
FWIW

The vacuum pump and gauges can be had off Amazon for less than 100 bucks shipped. Take your truck once to a shop for anything and you'll have spent more than that LOL!

-klb

1SG.Rob 07-10-2017 04:27 PM

Re: Factory A/C, what to do
 
Subscribed. Will be doing this in a few weeks if I can get my dash wiring harness sorted out.

hdff 07-10-2017 04:58 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by leddzepp (Post 7987634)
The a6 compressor does not cycle, it's either on or off.

The a6 will "lock up" and act like it's hard to turn, and your belt will squeal like a pig.

I went through 4 of them over the years on various trucks before I concluded I was wasting my time and went with a new aluminum a-10. No more belt squeals, no leaks, no problems. A rebuilt a-6 will fail, it's only a matter of time. They also leak at the front seal. I will never use one again unless it's the original one on the truck from the 70's and still functioning.

I restored the factory AC in my 68 a few weeks ago, a-10 compressor and r-12. 36 degree air idling at a stop light in 100 degree heat without missing a beat.

where did you get your a10?

leddzepp 07-10-2017 06:35 PM

Re: Factory A/C, what to do
 
I bought my recent a-10 at autozone, they had a special going on a complete ac kit. Included compressor, a quart bottle of mineral oil (used with r-12), drier/receiver, and expansion valve. Was $325, $50 rebate/gift card made it $275.

A-10 will work with r-134, just need to use the compatible oil. Mine came with 3 ozs of oil already in it, and I think it was pag oil as it had a different appearance than the mineral oil. Just to be sure I drained it and filled it with mineral oil, spun it around a few times and drained it again. I did this a few times to be sure I had compatible oil for the r-12. A quart is waaayyy beyond enough oil to do this procedure.

Already Gone 07-10-2017 07:15 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by leddzepp (Post 7987830)
I bought my recent a-10 at autozone, they had a special going on a complete ac kit. Included compressor, a quart bottle of mineral oil (used with r-12), drier/receiver, and expansion valve. Was $325, $50 rebate/gift card made it $275.

A-10 will work with r-134, just need to use the compatible oil. Mine came with 3 ozs of oil already in it, and I think it was pag oil as it had a different appearance than the mineral oil. Just to be sure I drained it and filled it with mineral oil, spun it around a few times and drained it again. I did this a few times to be sure I had compatible oil for the r-12. A quart is waaayyy beyond enough oil to do this procedure.

Thanks Scott..

dmjlambert 07-10-2017 07:36 PM

Re: Factory A/C, what to do
 
Quote:

Originally Posted by leddzepp (Post 7987830)
I bought my recent a-10 at autozone, they had a special going on a complete ac kit.

So please tell me how do you go about getting one of those from a place such as Autozone? I just now called Autozone and they have no way of selling me an A10 because when they look up what compressor goes on a 1969 C10 it shows them A6 compressor. They don't know what A10 means. It seems to me (and them) they must have an application, specific year/vehicle/engine size in order to sell something that was not intended for the truck as manufactured. Are we talking about using the same brackets, or are you guys who use an A10 fabricating something? Are the fittings exactly the same as on an A6?

leddzepp 07-10-2017 07:46 PM

Re: Factory A/C, what to do
 
1 Attachment(s)
Go down to autozone and tell them you want an ac compressor for a 69 truck...then look at all the options that come up. It will be obvious from the pic which one it is. The people there have no clue unless you lead them by the hand. Here is a pic of the kit with a part number.

leddzepp 07-10-2017 07:50 PM

Re: Factory A/C, what to do
 
1 Attachment(s)
The a10 bolts right up to the factory brackets and hoses or I wouldn't use it, lol. This is all the stuff that comes in the kit, with part numbers.

leddzepp 07-10-2017 08:05 PM

Re: Factory A/C, what to do
 
I took those pics at the beginning of May when I first bought the kit for reference in the future. I'll try and get a pic of everything installed when I get home from work late tonight or tomorrow.

dmjlambert 07-10-2017 09:04 PM

Re: Factory A/C, what to do
 
That would be great!

I just confirmed in person at AutoZone that it is not possible to get an A10 compressor by walking into AutoZone and asking for one. Applications for a 1969 pickup are for A6 compressor only, and there are no kits or individual compressors that is referred to as an A10.

With the picture of the box with part number B0743, that was the only way to find information about it. The detailed information he was able to find out about it included some technical information, but no information about the application, brackets to fit, fittings, etc. Nowhere in the documentation they have is it referred to as A10. The guy was knowledgeable but did not have memorized anything about compressor upgrades for an old pickup like mine.

This is kind of the same story of how there is no way to walk into an AutoZone and just get a 12SI alternator. You must know the part number or application.

dmjlambert 07-10-2017 09:25 PM

Re: Factory A/C, what to do
 
Also, looking on the AutoZone web page it shows this kit B0743 with part number 58098 is an A6 compressor. http://www.autozone.com/cooling-heat...3_246189_34477

Already Gone 07-10-2017 09:29 PM

Re: Factory A/C, what to do
 
Quick Google Serach this morning found this. Not plugging just sharing info.


http://www.brotherstrucks.com/64-74-...tinfo/ACC472A/


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