CUTLASS Discusson- Leaky Azz R4 Compressors...152a Experimental time.

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
I'd like to think that I have a halfway decent understanding of the A/C system on the Olds G-bodies. No expert, but I have successfully rebuilt, flushed, recharged, replaced, almost every single part of the system on several of the cars I've owned over the years.

I'm working into finally getting started on messing with the 85. My idea said to get it somewhat roadworthy and However, several years ago, I found that the system is super low on refrigerant and didn't kick on when running. When you press one of the schrader valves, it hisses a bit, so there seems to be something left, but not enough. There's evidence of some oil weepage around the front compressor seal, so I'm figuring that's where it, or at least most of it, went.

I've probably got about 22 pounds of R12 left, and that sh*t's made out of Unicorn golden poop. Don't want to waste it, but figured I got to ensure better sealing on these dumb azz R4 GM AC compressors. I have every single part to completely replace the entire HVAC system, but I figure I'll do that when it's time for the complete teardown and ressurection.

For the last 10 years or so, I've heard about the Air Duster cans changeover. Never gave it much thought before. Kinda blew it off and thought it was a disaster waiting to happen. But with the cost of R-12 out the roof, I started looking into it more, mainly for leak testing.

I researched it and ran across one video that made me figure I might go ahead and try it. What have I got to lose? Worse comes to worse it kills the system. The guy had this car he got from a junkyard, had no idea of the condition of the V5 compressor he had in the car, just that it had been converted to 134a at some point. He sucked it down, recharged it with Air Duster cans, and it blew cold. Big deal. But the convincing part is, he made another video 7 years later as a follow up. He had taken the car on several trips and the clutch was making noise and not working right, so he decided to put a brand new V5 compressor on it and a new accumulator. Spruced up the system and...recharged it with Air Duster. The video goes on to take the compressor apart and he went through it and it was surprisingly clean. During disassembly he found out why it was noisy. It was a remanufactured unit and wasn't a quality rebuild, and they cut the welds down on the pulley to clutch connection when they resurfaced it. That's where it broke.

7 years. From a junkyard recharge. Granted, he had to top it off about once per season or so, but it's still pretty impressive. I had since researched more and it seemed like when people actually took the time to do a proper evacuation and care in re-sealing the quirky R-4. Two of the most problematic areas that most already know about R-4 compressors is the case o-rings and the front seal leaking.

If treated just like a 134a retrofit, it supposedly seems to do an excellent job doing its thing, without the high head pressures. Has properties that match R-12 fairly close on the data sheets. Reason I even brought it up is last week I was cleaning out a closet and on the top shelf, I found a box with about four 12-oz cans of some of those Air Duster canisters. And this stuff is the pre-bitterant additive. Not sure if it would make a difference, but this is some pure 152a canisters. Never bothered to take any of that air duster refrigerant thing seriously, until now. I looked on the canisters and found it had a refrigerant in it, called R152a, or dioflourethane or some sh*t like that. I got to thinking at first I'd just use it to charge the system partially, fix any leaks, suck 'er down and if good, jam 3 lbs of R-12 in the system. Then I got to thinking - I got enough to use one can for leak testing, and 3 cans for a "full charge". Why not do a full ride experiment?

Another thing I found out is that the single pass condenser used in factory G-body systems is MUCH better for 152a conversions than 134a conversions. The amount of heat given up to condense is better for the 152a in the stock systems than the cross flow types. Plus, there's not too much complaints from people using the same stock orifice tube since the properties closely match R-12 performance. But yet a lighter charge. About 36 oz instead of 52 of R-12. Still will go by pressure.

I'm skeptical. And I will be until I see it for myself. But like I said, the system will be torn out completely at some point, so why not give it a whirl? There are some claiming 33 and 34 degree outlet temps driving around town. Which might have something more to do with the pressure cutoff switch on the accumulator as well. It needs to be adjusted about 3 lbs or so, based on some of the things I'm reading. And a change to POE. Probably not PAG. I heard it works ok with 152a, but it also would be better in a new, clean system that's never had mineral oil in it. I have read a lot of sludge stories about PAG and mineral oil not getting along.

The plan is to remove the existing factory hoses, but re-using them. Flush out the entire system. Put in new o-rings stem to stern, a new white stock orifice tube. A new accumulator, and tear apart and re-seal the existing compressor. Flush it all out while I'm in there. Then, stick it all back together, suck it and hold it, (which is opposite than your mom :p ) , and if good to go, charge in 3 cans then and see what happens.

There's no set time table for this since it's just starting into the planning stages, but this 152a conversion is relatively CHEAP (roughly 9 bucks per pound buying by the can) compared to 134a or R-12. So we shall see. Even if it breaks, it won't matter. But if I need a bit more, for about 7 bucks or so, I can get another can.

Willing to listen to experiences, or thoughts, or any other discussions on this. Here to learn and this is something different. I have noticed as well, you can't readily just buy a 30 lb can of 152a. I'm not worried about leaking through the hoses. I got a feeling a little add here and there won't be an issue.

Opinions?
 
  • Like
Reactions: 1 user
Oct 14, 2008
8,806
7,746
113
Melville,Saskatchewan
Give it a try, bet it will work fine. I used them on my 88 till the R4 seized, leaking oil and noisy, cooled really well. Yeah, not a fan of R4 compressors, a pain to work on and almost always leak somewhere and make noise. Those reman R4 compressors always seem to die within a short amount of time. The completely new ones seem better and get a heavy duty version. I have the SBC R4 sbc serpentine truck brackets on my 70S. Their is Sanden adapter brackets, going that route if I go to aftermarket A/C. Why GM used those garbage compressors for so long is beyond me.
 
  • Like
Reactions: 1 user

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
First order of business, when you don't know what to do first...make the decal! Looks official. I ripped it off from the ACDelco decal and transgendered it to my own. Since the SAE-1661 standard talks about retrofitting to 134a, it's the same exact method to go to 152a as well, so for me, it sounded appropriate to leave it. I can't see leaving in that section in that says who converted it and their address...I initially thought about leaving it in and putting in the name "N. Unya". With the address as "100 Main St., Anytown, U.S.A., 00000." but then said wtf, and just took out the entire section.

152a retrofit decal.jpg


The original I based mine from.

1676149564579.png
 
  • Like
Reactions: 7 users

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
Did a little more unscientific research on this subject. Let us examine a few things, both anectdotally and factually about R152a.

Anecdotally-

People who have done this experiment have reported no issues when the system was properly converted as you would going from R12 to R134a. New accumulator/dryer, new orifice tube, and proper mineral oil flush out to use POE. Good working equipment was reported to have lower high side pressures which means the R4 compressor didn't have to work as hard. And 134a tended to have higher pressures all around so it would put a strain on the compressor.

Even people that were less than ideal mechanics could get R152a conversions to pump out low 40s vent temps on hot days having shown NO earthly idea of why they're doing what they're doing. I've seen some discussions talk about variable orifices and different sizes, colors, etc. MOST of the GM conversions I've seen are using the stock GM orifice tube.

Using R152a in older, 60s/70s cars with A6 compressors with TXVs and POAs and stuff, you would have to adjust the POA to make good use of the R152a. On our G-bodies, the accumulator-mounted low pressure cutoff switch is where you want to look. With R12 switches, you're looking at around 25 psi or so, and the 134a would need to be around 4 psi under that. Same with the R152a. People probably hadn't thought about this and did not adjust the switch accordingly. Some are ajustable, so may not be. You would have to look. In between the electrical connector, you may see a small slotted screw head. If so, you can adjust it. Take a small flat blade and back it off about 1/4 to 1/3 turn CCW or thereabouts. You can use your gages to dial it in precisely, but that should get you in the ball park. This needs to be on a somewhat cool ambient temp because on hotter days, the refrigerant likely will stay above that point anyway. Point is, if you don't lower the cycling pressure, the compressor will cut off continuously until pressures reach 25 psi. This will result in poor cooling performance of the system, and way too many cycles of the clutch when not needed. Lower it to about 20-ish, and if the evaporator starts to freeze up, the pressure will dip below 20 and cut the compressor off until it "melts" and raises pressure again. If it didn't have the switch, you'd likely iceblock the evaporator on a warm day when you would expect it to cycle more often. Again, if someone used POE oil in an R134a charge, and did it right, R152a would just be an easy suck and dump operation.

Even though rated as slightly flammable under certain conditions, people have tried to light the gas. Nothing. Blows the flame out. It's less flammable than butane and less toxic than ammonia, but somehow the gubment doesn't like it as a replacement for your car equipment. Interestingly, it's seemingly fine to use Envirosafe refrigerants, but it's propane/butane mix. It's more flammable than R152a. Hmmm. The data against using R152a in a car's R12 system doesn't add up. Money, patents, and lobbying? Another hmmmm.

The EPA would go nuts if they watched you just crack the refrigerant line on your R134a car system and let it escape. Yet, if you bought one of those older Air Duster cans that used 134a in them for propellant, you could spray it in your house directly on your computer components. No big deal. R134a is 10 times less of a global warning potential than R12. But yet R152a is 10 times less than R134a. Apparently, they say the 134a and 152a are not ozone depleters.

Some of the videos I saw show most systems running around 30 psi on the low side, and 175-195 on the high side and cooling off the people tank very well with low to mid 30s vent temps. Contrast that with 250-300+ with R134a system high pressures and you can see where the R152a may help your poor little R4 compressor survive longer.

Factually-

3.25 lbs, or 52 ounces of R12, typically makes up a full G-body A/C charge, with 6 ounces of mineral oil for lubrication. Best to check your CSM or underhood decals on the HVAC components for more information.

Molecular weight of R12 is 120.908 g/mol. R134a is 102. Thus, it's 84.36% of R12. This is where that 80-85% thumbrule comes from for conversions. That said, R152a is 66.051 g/mol. Or 54.63% of R12. (R1234yf is 114, so very close to R12 anyway, so that'd be a wash. R1234yf has its own issues, but just used as a comparison). So for a 52 ounce R12 system, an equivalency charge of R152a would be 28.41 ounces for a replacement charge. Since most of those cans come in 10 oz sizes, 3 cans would be a perfect charge size. You'll always lose a tad when purging and other minor losses cuz you usually can't get it all out of those cans of refrigerant anyway. Even if you did, 1.39 ounces of refrigerant extra probably won't make much difference.

R12 systems already converted to R134a with a POE oil charge is ready to go. Fix any leaks, vac and go. POE is VERY hygroscopic. Meaning it will suck up water like a sponge. It doesn't want to let it go, but it will. It's not a great idea to get more oil than what you need. Long exposures to the air allow it to suck up moisture. Which is bad. However, if you use the POE oil soon after opening, and put together the system and vacuum it down, it will reduce the moisture in the system. Lesson to take away is to don't dally when it's time for the POE oil, just to be on the safe side. Even ACDelco seals the bottles in a vacuum packed aluminum foil pack to ensure long shelf life. Old POE oil you've had on the shelf for the last 3 years or so probably would need to be pitched if it's been open to atmostphere.

According to tech data sheets about R152a- "It is a direct drop-in replacement for R-134a and a non-direct replacement for retrofitting R12 and R-409A (change the oil type)." Further investigation finds although the toxicity level is low, the government doen't like 152a for mobile R12 conversions because of it's flammability rating higher than that of R1234yf. Otherwise, there's absolutely no scientific evidence to say that R152a is bad for your system and poses a danger much more than "flammable under certain conditions" thing they throw out there. Toxicity is low, although they keep trying to bring that up as a problem area as well. I'm not convinced.

According to tech data sheets, R1234yf has an auto-ignition temperature of 405 deg C. R152a has an auto-ignition temperature of 440 deg C. However, R152a is listed as having a slightly higher flammability than R1234yf. wtf?

R1234yf has a global warming potential rating (yeah, it's a thing) aka, GWP rating of 4. Pretty good. R134a has a rating of 1430. And R152a has a rating of 124, or a 91.33% saving the planet factor better than R134a. So if you really gave two f**ks about the planet, R1234yf or R152a would be better choices than R134a. Not to mention, R12 rating is over 10,000, so we all know it sorta sucks. But it was super stable and non-flammable, so patent losses REALLY made it go away.

R152a is in the majority of these "Air Duster" cans. It's normally just ONE component, R152a, and maybe a bitterant added to keep the huffers from buying it all up by the case. I'm imagining the bitterant is so low in concentration it may not even matter, but for me, I'll choose ones without it. Apparently it doesn't seem to matter for most of the ones I've seen on Youtube.

Price factors-

Depending on where you go to get it, you can get these R152a "duster cans" just about anywhere in all sorts of sizes and prices. USUALLY, you can find the 10 ounce cans in the neighborhood of around 6-ish dollars USD. Sometimes they have sales at places like these warehouse clearance stores. So if you wanted it, it's there. In contrast, I've seen R134a around 12-15 dollars per pound and more even buying it in bulk 30lb canisters. So even buying R152a in 10 ounce cans, it's costing you about 60 cents per ounce, thereabouts, so <$20 for a complete, full G-body recharge. 44 ounces, or around 2.75 lbs of R134a. At around 90-93 cents per ounce, you're looking at around $40+ per fill. And make it harder on your wallet AND your compressor. Obviously, if you get free sh*t or find discounts, the prices will and can vary, so you do your own math, but generally speaking, R152a is pretty friggin' cheap comparatively speaking.

Bottom line-

There's very few downsides of taking on this experiment. I look at it like this- people running cat converter test pipes for 8 years don't seem to have much issue. Using R152a should be ok as well. It actually likes the serpentine single flow stock G-body condensers it seems better than the crossflow style. Who'd have thunk it. HVAC pros tend to think if the evaporator in cars was just a tad bigger, R152a would be even better suited in those situations.

I find it interesting that R152a is hardly available anywhere in a 30lb jug, unless you buy a pallet full of them. But air duster cans? All over the place.

Either way, I think I'm going to inch forward on this. Moreso just to see if it actually works for my own education.
 
  • Like
Reactions: 4 users

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
Found out some more information about R12 and R134a.

When measuring stuff,like length, there's usually nomenclature to convert to units that's comparable. So when measuring molecule sizes, a tape measure ain't gonna cut it. I guess in the scientific world of atoms and junk, they use computerized microscopes and stuff to look at these sort of things. Anyway, the unit of measure is usually an Angstrom. 1 Angstrom (A) = 1 ten-billionth of a meter. That's super tiny.

Water molecules are small. Comes in at 2.68 Angstroms
R12 is almost twice as big at 5.09 Angstroms
And here's an interesting find- R134a is even BIGGER than R12. At 5.24 Angstroms.

If this is correct, then the old axiom of R12 hoses needing to be changed out for R134a barrier hoses because R134a molecules are smaller and leak out of the R12 hoses easier can be tossed under the bus. While true that R134a has a lower molecular weight than R12 by just a hair, R134a has 2 Carbon atoms vs. R12 having only one Carbon atom. To note, R152a also has 2 Carbon atoms, so it's going to take up some retail space. Although the molecular weight is about 65% of R134a, I've yet to find a measurement of the diameter of the molecule.
 
  • Like
  • Useful
Reactions: 1 users

ck80

Moderator
Moderator
Supporting Member
Feb 18, 2014
5,742
9,114
113
Found out some more information about R12 and R134a.

When measuring stuff,like length, there's usually nomenclature to convert to units that's comparable. So when measuring molecule sizes, a tape measure ain't gonna cut it. I guess in the scientific world of atoms and junk, they use computerized microscopes and stuff to look at these sort of things. Anyway, the unit of measure is usually an Angstrom. 1 Angstrom (A) = 1 ten-billionth of a meter. That's super tiny.

Water molecules are small. Comes in at 2.68 Angstroms
R12 is almost twice as big at 5.09 Angstroms
And here's an interesting find- R134a is even BIGGER than R12. At 5.24 Angstroms.

If this is correct, then the old axiom of R12 hoses needing to be changed out for R134a barrier hoses because R134a molecules are smaller and leak out of the R12 hoses easier can be tossed under the bus. While true that R134a has a lower molecular weight than R12 by just a hair, R134a has 2 Carbon atoms vs. R12 having only one Carbon atom. To note, R152a also has 2 Carbon atoms, so it's going to take up some retail space. Although the molecular weight is about 65% of R134a, I've yet to find a measurement of the diameter of the molecule.
From what I recall reading, the big difference was the mineral oil in the r12 system would impregnate the hose material and it was the mineral oil in the hose that reduced molecule leakage in a non-barrier type.

If you had the same non-barrier type hose with the r134a without the mineral oil embedded in the hose rubber, the refrigerant molecules could then pass through the rubber over time.

So, the great equalizer becomes, in a converted flush/refill situation re-using a hose that formerly had a full mineral oil charge, there would be residual mineral oil already in the rubber and it was that oil which acts as its own 'barrier'.... but, if you had a non barrier hose, and it hadn't had an extensive history of mineral oil to saturate it, it would leak down the 134a.
 

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
From what I recall reading, the big difference was the mineral oil in the r12 system would impregnate the hose material and it was the mineral oil in the hose that reduced molecule leakage in a non-barrier type.

If you had the same non-barrier type hose with the r134a without the mineral oil embedded in the hose rubber, the refrigerant molecules could then pass through the rubber over time.

So, the great equalizer becomes, in a converted flush/refill situation re-using a hose that formerly had a full mineral oil charge, there would be residual mineral oil already in the rubber and it was that oil which acts as its own 'barrier'.... but, if you had a non barrier hose, and it hadn't had an extensive history of mineral oil to saturate it, it would leak down the 134a.
While this is interesting take on the hoses, the point that was trying to be made was the old wives tale was busted in that again, if these measurements are true, R134a doesn’t leak through because it’s a smaller molecule than R12. Because it’s not. So any converted system from R12 should be fine. Mineral oil has benefits. Why wouldn’t POE do the same? I’d still like to see some actual data instead of anecdotal evidence and a story.
 
  • Like
Reactions: 1 user

ck80

Moderator
Moderator
Supporting Member
Feb 18, 2014
5,742
9,114
113
While this is interesting take on the hoses, the point that was trying to be made was the old wives tale was busted in that again, if these measurements are true, R134a doesn’t leak through because it’s a smaller molecule than R12. Because it’s not. So any converted system from R12 should be fine. Mineral oil has benefits. Why wouldn’t POE do the same? I’d still like to see some actual data instead of anecdotal evidence and a story.
I get it. Where I was coming from is you'd hate to see someone go get a bunch of expensive NOS non-barrier hoses, do a fresh charge of 134a, and be disappointed because now it both didn't keep charged and it would be a pain to go back to r12 to start with as the hoses risk black death in the system.

Back in the early-mid 1990s there was an ASE panel with recommendations regarding the changeover from r12 systems to r134a systems that did a bunch of studies. Some of their papers back then were where I'd read about it being their conclusion that used non-barrier hoses should be safe with minimal loss of coolant molecules, but, unused new hoses should be barrier type. I don't have them anymore, or if I do, they're squirreled away somewhere I haven't seen in forever along with piles of carb hot air documents and old smokey yunick writeups from back in the day.

Back to an opinion: Thinking back to the pre-ozone awareness and pre-greenhouse gas state of things, when your local ames/caldoor/Kmart sold r12 cans on the shelf in the auto aisle, Joe schmoe would just top off the a/c many springtime before driving if it wasn't quite as cold. Point being, as a layman, it wouldn't surprise me if it took years of slow absorbtion before the slow of molecules was stopped up by combined mineral oil and r12 molecules.

It was so long ago I don't recall what the controls were, ie, how old the systems they were testing the 134a use in. But, it wouldn't make sense for them to use brand new or 18month old components, because the impact they would've been studying in the phase out was when the 6, 8, 10 year system eventually needed a recharge but r12 wasn't being made anymore, how would those parts handle a changeover.

A Google search showed me SAE Technical Paper Series #930230 & #932905 dealt with field testing retrofits, and maybe one of those is one of the ones I'm thinking of. But I also didn't case enough to pay the cash to get behind their pay wall for some 30 year old reports. Curious, but not really that invested. Although, maybe there is someone here with access that doesn't require paying and is more curious that takes a peek?
 

69hurstolds

Geezer
Supporting Member
Jan 2, 2006
8,088
17,308
113
Curious, but not really that invested.
Exactly. I honestly don't care that much about doing extreme amount of research on all this. I'll never do A/C work for a paycheck, so it's just some interesting things I've found by trying to learn more about this 152a changeover. R134a is great in the systems designed for it, but for R4 compressors, I really do think the higher head pressures shorten the life of the compressor. If you think about it, it's very similar to one of those mini-hot dog air compressors with the teflon sealing ring(s) for the aluminum setup and even the oiling isn't going to save it from heavy pressures, along with those reed valves. And since R134a is starting to get stupid expensive like R12 did, it's only worth finding out if 152a actually is worth any of the potential low-level risks associated with using it.

Finding NOS hoses may not be such a big deal. At some point in the mid-90s, my GM parts guy told me ACDelco started using "R134 type" hoses for everything, including the three units I bought from him then, even when expected to be used in an R12 environment. I didn't care so much as I still had plenty of R12 so 134a was this new stuff at the time. Trying to remember the details of what he said, but IIRC, he mentioned the main difference was the nylon barrier layer. Also, GM even specified there's no reason to change O-rings unless they're leaking already when doing a retrofit from 12 to 134. So that leads me to believe there's a lot of BS surrounding all the "concerns" of which refrigerant gets used when and where. I think it's more $$ and politics than anything else.

That led me to wonder since I had "nos" hoses, which were simply new replacement hoses when I bought them, would there be a way to tell which type they were? Maybe. I haven't dragged them out and looked at them yet, but apparently the full-on barrier hose would be marked with something that equates to code SAE J2064 originally issued in 1993. The latest version (04/2021) states: "The scope of SAE J2064 covers coupled hose assemblies intended for containing and circulating lubricant, liquid, and gaseous R-134a, R-152a, and/or R-1234yf refrigerant in automotive air-conditioning systems."

And also includes this blurb in earlier 2011 version:
"A hose marked “J2064 - R134a”, “J2064 - R-1234yf” or “J2064 - R134a/R-1234yf” signifies that it has been coupled, tested, and has met the requirements of SAE J2064 for the marked refrigerant(s). A hose marked “J2064” without any reference to refrigerant signifies that it has been coupled, tested, and has met the requirements of SAE J2064 for R134a only. It is the hose assembly manufacturer’s responsibility to see that the assemblies meet the specified acceptance criteria for this specification."
 

ck80

Moderator
Moderator
Supporting Member
Feb 18, 2014
5,742
9,114
113
Exactly. I honestly don't care that much about doing extreme amount of research on all this. I'll never do A/C work for a paycheck, so it's just some interesting things I've found by trying to learn more about this 152a changeover. R134a is great in the systems designed for it, but for R4 compressors, I really do think the higher head pressures shorten the life of the compressor. If you think about it, it's very similar to one of those mini-hot dog air compressors with the teflon sealing ring(s) for the aluminum setup and even the oiling isn't going to save it from heavy pressures, along with those reed valves. And since R134a is starting to get stupid expensive like R12 did, it's only worth finding out if 152a actually is worth any of the potential low-level risks associated with using it.

Finding NOS hoses may not be such a big deal. At some point in the mid-90s, my GM parts guy told me ACDelco started using "R134 type" hoses for everything, including the three units I bought from him then, even when expected to be used in an R12 environment. I didn't care so much as I still had plenty of R12 so 134a was this new stuff at the time. Trying to remember the details of what he said, but IIRC, he mentioned the main difference was the nylon barrier layer. Also, GM even specified there's no reason to change O-rings unless they're leaking already when doing a retrofit from 12 to 134. So that leads me to believe there's a lot of BS surrounding all the "concerns" of which refrigerant gets used when and where. I think it's more $$ and politics than anything else.

That led me to wonder since I had "nos" hoses, which were simply new replacement hoses when I bought them, would there be a way to tell which type they were? Maybe. I haven't dragged them out and looked at them yet, but apparently the full-on barrier hose would be marked with something that equates to code SAE J2064 originally issued in 1993. The latest version (04/2021) states: "The scope of SAE J2064 covers coupled hose assemblies intended for containing and circulating lubricant, liquid, and gaseous R-134a, R-152a, and/or R-1234yf refrigerant in automotive air-conditioning systems."

And also includes this blurb in earlier 2011 version:
"A hose marked “J2064 - R134a”, “J2064 - R-1234yf” or “J2064 - R134a/R-1234yf” signifies that it has been coupled, tested, and has met the requirements of SAE J2064 for the marked refrigerant(s). A hose marked “J2064” without any reference to refrigerant signifies that it has been coupled, tested, and has met the requirements of SAE J2064 for R134a only. It is the hose assembly manufacturer’s responsibility to see that the assemblies meet the specified acceptance criteria for this specification."
One thing that may also help, although I don't have on-hand examples to compare, would be how the hose to fitting interface was secured/crimped. There was much ado about nothing back when they first started making changeover stuff, biggest wrench in the comparisons at the time was aftermarket quality on EVERYTHING was fairly poor. But, supposedly the barrier layer was just below the surface of the hoses, and as such, couldn't be crimped the way the pure rubber stuff was.

I'd wonder if looking at that connection would be a telltale sign?
 

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor