Upgrading 1987 R10 A/C to R134a parts / questions

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Blue Ox

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That one may be for a Suburban with rear A/C.
 

TX87R10

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oof
 
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TX87R10

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So I don't want to celebrate too early but looks like I was able to get the system back up and running with everyone's help. The blower motor has been cutting off for what seems like bad contact but it'll work for now.

Thanks again for everyone's help!

Now on to tint and a fresh suspension and ...
 

1987 GMC Jimmy

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I wouldn’t personally try to test the clutch without pulling vacuum and holding it on the system and then turning it by hand to prime the oil. It makes sense from the perspective of not wanting to waste 48 ounces of refrigerant on a bum compressor, but I get a bad feeling from running it semi-dry like that. For me, I’d just gamble. And that vacuuming it down should get any residual chemical flush out of it. I try to blow everything out as best I can, but when I vacuum it, I can sometimes smell the d-limonene (citrus oil) from the flush stuff.
 
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TX87R10

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I wouldn’t personally try to test the clutch without pulling vacuum and holding it on the system and then turning it by hand to prime the oil. It makes sense from the perspective of not wanting to waste 48 ounces of refrigerant on a bum compressor, but I get a bad feeling from running it semi-dry like that. For me, I’d just gamble. And that vacuuming it down should get any residual chemical flush out of it. I try to blow everything out as best I can, but when I vacuum it, I can sometimes smell the d-limonene (citrus oil) from the flush stuff.
Definitely. The flush I used had a smell like that and it's how I figured out where the liquid came from.

After running it not dry I decided to purge the new compressor. The oil in it was already black with chunks so I bought a new compressor and dryer and started from scratch again. After blowing the lines out over and over I vacuumed and it help then vacuumed for a lot longer to make sure. I feel much more comfortable that it will hold now.
 

Red 87

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I had a company change mine over about 4-5 years ago (paid a pretty penny, too)...and then the ACDelco compressor they installed crapped out just after the 1-year warranty was up. I bought a new compressor, accumulator/drier, orifice tube and o-rings/PAG oil and replaced it myself a couple of years ago, but then after a little over a year it stopped blowing cold. This time I had a local shop down the road (who we've used for our other vehicles) diagnose the issue, and they said it just needed to be charged up. They also put a dye in, in case it started leaking. I drove it one day, and the a/c worked great. The next day...no cold air. I took it back to them and they found a loose connection, charged it back up and didn't charge me anything for the refill. It was even colder than before and worked great the rest of that day and the next. It then sat for a few days and the next time I started it (last week)...no cold air again. I haven't taken it back to them, because now I'm not sure I can trust them to fix it.

I'm super close to pulling the trigger on the Vintage Air setup...just for the fact that it eliminates a lot of this old crap & technology. My blender door doesn't work very well, the sliders on the controls don't move all the way over and I replaced the original heater core (leaking) several years ago with one of the aluminum cores from AutoZone, and the size difference between the stock one and this one leaves a gap where cold air can get around it...so it doesn't heat very well when it's really cold out. The Vintage Air would take care of all of that.
 

jake wells

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If you want to you can use in a drop in replacement freon and it is capable with the refridgerant oil used by R12.
It is called R426A you don't have to change a thing and it is just as efficient as R12 and works much better than R134A.
 

Galane

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When converting from R12 to R134a you should use an oil with additives to make it compatible with any remnants of the old mineral oil left behind even after a really good flushing, and draining of the old oil from the compressor. One of those is Airsource 8201. R134a retrofit kits that include oil in the refrigerant can or a separate can of oil should already have compatibility additives.

As of 2017 R134a is being phased out for R1234yf, which of course uses different oil. Oil for R1234yf will work with R134a but not the other way. https://www.denso-am.eu/media/corpo...essor-oil-and-refrigerant-mixing-old-and-new/

If you get some wild idea to use an electric driven AC compressor, those need a POE oil instead of the PAG oil used in mechanically driven compressors. POE is much more electrically insulating than PAG, so out of an abundance of caution POE is used to prevent any possibility of an electrical short (and potential fire) in the compressor.
 

TX87R10

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Since you hear hissing, here's a vacuum diagram for FI trucks.

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Probably a dumb question Craig but is it reasonable safe to say the hissing / vacuum issue is a problem for the fall when it cools off and I need heat or are there any harmful side effects? Trying to tackle one thing at a time and given I've got nice cold A/C blowing again I didn't want to fuss with it yet if I don't need to.
 

Blue Ox

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Does it hiss constantly or just when you change a setting? Mine will make brief hissing noises while the doors are repositioning.
 

Craig 85

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I was going to ask the same. All 8 of the square bodies I've owned over the years have hissed/purged as you cycle through different modes, even when new. If it's a constant hiss, it's causing a vacuum leak. Since you're fuel injected, the computer may adjust air/fuel for a small leak, not so much on my carbed truck.
 

TX87R10

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Yeah it hisses pretty loud when adjusting it. There is no heat coming out yet when I checked but currently but I don't hear the hissing when it's running or stopped after some short period of time. I can hear it if I move the levers for the temperature control when the truck is off too if that matters.
 
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