R-12 to R-134 conversion

[jss06c6]

Gents,

About to swap over to R-134. I've got the compressor and accumulator. To be clinically correct, I'll need to swap out the high pressure line to R-134 configuration. Anyone with one in good condition to sell, please send me a PM, otherwise I'll TIG in a new high pressure port.

What about the high and low pressure switches. Are the R-12 switches compatible with R-134 and the higher pressures? If they need to be replaced, are they available?

Thanks!

Steve



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[GOLDCYLON]

Gents,

About to swap over to R-134. I've got the compressor and accumulator. To be clinically correct, I'll need to swap out the high pressure line to R-134 configuration. Anyone with one in good condition to sell, please send me a PM, otherwise I'll TIG in a new high pressure port.

What about the high and low pressure switches. Are the R-12 switches compatible with R-134 and the higher pressures? If they need to be replaced, are they available?

Thanks!

Steve



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If you are going to do it right you should replace the condenser as well as they are different. No the switches are not compatable. I suggest not doing it if you can avoid it as the R134 system conversion won't be as cooler as the R12 unless you replace everything. GC

[jss06c6]

134 operates at a higher pressure and expansion is the cooling process, so I get the need for proper pressure switches, but can't make the case for a different condenser unless the R-12 version is working at it's pressure limit, or, the R-134 unit has significantly more heat exchange surface area. I would be more inclined to think the expansion valve is different for R-134 to get proper cooling phase change (liquid to gas). Interested in thoughts.

I'm not wanting to chase R-12 at the price I have to pay for it. I'd rather modernize the system while I've got it down.

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[secondchance]

High pressure switch for 134a opens (and open is fan run position) at 240 psi or close to it - high pressure switch for R-12 will not work correctly. Also, high pressure switch for 134a is almost none existent.

[jss06c6]

High pressure switch for 134a opens (and open is fan run position) at 240 psi or close to it - high pressure switch for R-12 will not work correctly. Also, high pressure switch for 134a is almost none existent.
Thanks for the detail. I certainly understand the higher pressures in 134A. When you say "high pressure switch for 134A is almost non-existent", what does this imply? Do you mean they aren't available?

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[-=Jeff=-]

I believe the stock cycling switch has a screw adjustment between the prongs.. turnis 1/4 turn CCW for r134a

[-=Jeff=-]

High pressure switch for 134a opens (and open is fan run position) at 240 psi or close to it - high pressure switch for R-12 will not work correctly. Also, high pressure switch for 134a is almost none existent.

You can find them, just need to know where to look

[jss06c6]

I believe the stock cycling switch has a screw adjustment between the prongs.. turnis 1/4 turn CCW for r134a
Thanks Jeff!

Steve

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[rossgn49u]

Curious as to why switching from R-12 to R134?

[jss06c6]

Availability and cost of 134a vs 12. Current system has a slow leak. PITA finding and buying R-12. Just not worth the headaches to me. If I were buying another pre-94 Corvette and the prior owner had done a proper job of converting to 134a, I would pay extra for the upgrade.

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[XfireZ51]

I don't think Marc will have a problem with me posting his response to my inquiry re:134a. Looks a bit less involved than we may have believed. I will swap out the high side switch, just in case, but otherwise...

Hi Dominic,

The OE o-rings and switches are compatible with R-134a refrigerant. I have a GM service bulletin advising that. Only three things are needed. 8 oz. of PAG oil, service port adapters for R-134a and the refrigerant.

When installing a new compressor, it's a good idea to install a new filter/dryer and a new filter/orifice.

Best regards.

Marc

[jss06c6]

Excellent information.. wouldn't expect anything less from Mr. Haibeck!

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[S.hafsmo]

I don't think Marc will have a problem with me posting his response to my inquiry re:134a. Looks a bit less involved than we may have believed. I will swap out the high side switch, just in case, but otherwise...

Hi Dominic,

The OE o-rings and switches are compatible with R-134a refrigerant. I have a GM service bulletin advising that. Only three things are needed. 8 oz. of PAG oil, service port adapters for R-134a and the refrigerant.

When installing a new compressor, it's a good idea to install a new filter/dryer and a new filter/orifice.

Best regards.

Marc

This is correct? You do not need to replace expansion valve, compressor, condenser, pressure switch etc.?

Is there any way to tell if the system is already converted?

Drier and orifice recommended, I see.

[WARP TEN]

This is correct? You do not need to replace expansion valve, compressor, condenser, pressure switch etc.?

Is there any way to tell if the system is already converted?

Drier and orifice recommended, I see.

Yes. Marc once showed me the GM service bulletin on the subject back in the late '90s when I had my '93 converted. And I think that the fill valves are different for the R-134a than the R-12 but not certain; others know better. --Bob

[-=Jeff=-]

If I recall fill for R134a is maybe 90% of R12

[mhobtr]

The low pressure switch is the same but there is a small screw between the wire terminals that is turned to adjust the low pressure cutoff.

IIRC the low pressure cutoff is 24psi for R-134a and 22psi for R-12 but you need to check the service manual to be sure.

[Ccmano]

I can tell you that back in the day when I was doing these we only replaced the orifice valve (R134 specific), installed an R134 adapter, evacuated the system, added PAG oil and recharged with R134. A they always worked just fine. I believe any orifice valve you get today will be R134 compatible.
H
:cheers:

[viper107]

i have just allways screwed on the 134a fittings to the hoses and shot the system, blows ice cold if the system is healthy, never changed nothing

[jss06c6]

Old thread..

I replaced my condenser (source of leak), compressor (R134 version), dryer and orifice tube. No pressure switches were changed.

I changed the compressor to a NOS unit "while I was in there". Dryer swap good practice. Put in 8 OZ PAG 100. Vacuum for 2 hours. Tight as a drum 24 hours later.

System took 1.83 lbs R134A. Blows cold with no issues.

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[Ccmano]

Looks like I need to replace my condenser. I plan to replace it and the dryer/accumulator. The compressor was replaced a few years ago. Can't tell if the system is running on R12 or R134a. I plan to recharge it with R134a. Does 4.5oz of PAG 100 oil (per the manual) sound correct since I'm not doing the compressor?
H
:cheers:

[-=Jeff=-]

What do the fittings look like for the high side and low side, that will help to determine R-12 or R134a

[Ccmano]

What do the fittings look like for the high side and low side, that will help to determine R-12 or R134a

The fittings are R12. But that doesn't mean someone didn't use adapters and R134a a few years ago when the compressor was done. Especially since it was in CA at the time where R12 is a big no-no.

Also trying do determine if I need a white or a black orifice tube.
H
:cheers:

[-=Jeff=-]

Gotcha as for the orifice tube. Which are listed for the car?

[XfireZ51]

All I did was replace O-rings, new PAG oil in compressor and different fitting for evaporator/dryer.

[Ccmano]

Gotcha as for the orifice tube. Which are listed for the car?

The white tube is standard. It appears the black tube is an optional automatic adjusting tube for severe climates. Anybody ever use one?
H
:cheers:

[PhillipsLT5]

Years ago I installed a severe climate tube in Hot PHX with R 12 worked fine, blew 38-40 degree air out, dont know about the color

[Matt B]

As mentioned in another threat I my R-12 was drained during import into Europe. So now I need to switch to 134a as R-12 is illegal here...
However, reading through this threat left some confusion. Appreciate if someone can add some clarity on the following:

- switches: it was said that R-12 high pressure switch will not operate correctly but can be adjusted by turning the adjustment screw 1/4 ccw. So no other switches or adjustments other than that needed, correct?

- PAG oil: I'm an A/C dummy so sorry for that stupid question (I know there are no stupid questions but I think this one is...) but the oil is not only inside the compressor but the entire system, right? So, I need to remove the compressor from the car, drain it and also flush the rest of the system?
However, in an case I can re-use the OEM compressor with no further modifications?

- Orifice tube: do I need to swap it? If so, Rockauto lists a variety:
*GM GENUINE 155151 {#03033879, 3033879, 3033879OEM}
*ACDELCO 155754 {#19189768, 88919511} - "OE replacement"
*ACDELCO 1550120 {#19189841, 89032868} - "Optional Automatic Adjusting Orifice Tube For Normal Climates Under 105 Degrees"
*ACDELCO 1550122 {#19189843, 89032872} - "Optional Automatic Adjusting Orifice Tube For Severe Climates over 105 Degrees"
Which one is correct? Germany is not a super hot place, however does the "hot climate version" maybe improve the cooling power? I heard that the ZR has it's limitations here...
Will I need a remover tool to get the job done or will needle nose pliers work?

I already have a new dryer on the shelf which I will install including some fresh O-Rings. Now I need to collect the rest and plan the actual work.

Sorry for all these questions but as spare parts are sometimes hard to come by over here I became very careful to not destroy things due to stupid mistakes ;)

[Subfixer]

I converted my 92, but it was not easy.
R12 switches and hoses are SAE threads (American).
All switches and hose fittings for R134a are Metric.

I bought entire new 95 R134a system; evaporator, condenser, dryer, hoses, switches.
Took months to gather all the correct stuff.
Took about a week of wrenching to get it done.

The most difficult part to get was the hose set the attaches to the compressor. No one makes it and the hoses out there are all built incorrectly.

Here are my build/problem threads
http://zr1.net/forum/showthread.php?t=30711
http://zr1.net/forum/showthread.php?t=30748

[Ccmano]

I don't think Marc will have a problem with me posting his response to my inquiry re:134a. Looks a bit less involved than we may have believed. I will swap out the high side switch, just in case, but otherwise...

Hi Dominic,

The OE o-rings and switches are compatible with R-134a refrigerant. I have a GM service bulletin advising that. Only three things are needed. 8 oz. of PAG oil, service port adapters for R-134a and the refrigerant.

When installing a new compressor, it's a good idea to install a new filter/dryer and a new filter/orifice.

Best regards.

Marc

Please note this post. I've done exactly this on several cars including my current car. I usually change the orifice valve too. AC works perfectly!
H
:cheers:

[mhobtr]

I don't know about the high pressure switch but the low pressure switch is adjustable by turning a screw between the terminals.

The low pressure cut off is 2 lbs lower for R12 than R134a but the switches are the same. If you buy a new replacement, it will be set for R134a.

I'm still running R12 and I discovered this when I had to replace a faulty LPS.

[Matt B]

Sorry, I have to dig this out once more as I'm close to my plenum pull and will do the r134 conversion then.

Question is about oil and I still haven't (but might have overlooked) found a sufficient answer. How and to which extent (!) the old mineral oil has to be removed? It can't be simply flushed with r134...

I'm asking because particularly the above mentioned PAG oil is to my knowledge not compatible with older mineral oils. The alternative would be PAO 68 which can be mixed with minerals, but it's PAG that is explicitly mentioned.

So are there any efforts recommended by the bulletin to remove the old oil other than draining what's in the compressor and replacing the dryer?

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[Thomas ZR-1]

I refill the R12 systems with the regular R134a for about 10 years now via R12 to R134a adapters and replacing the following: filter dryer and ALL pipe o-rings.

Glaub mir Matthias, funktioniert problemlos...und: anstatt 960 Gramm nur 840 Gramm K?ltemittel einf?llen wegen der anderen K?ltemittel-Dichte, sonst tut sich der Kompressor schwer.

[Matt B]

I did the conversion today. Following most suggestions I used PAO oil (which nicely blends with R12 mineral oil) following the shop manual guides.
I replaced the dryer by an AC Delco genuine part and added 105ml of oil into the inlet pipe. Pulled vacuum for 2 hours, system is extremely tight, no vacuum loss at all after 5 minutes.
Than I added 420gr r134 with the engine running and A/C "off". At 420gr I switched on the A/C as described in the manual and added another 420gr to reach 840gr as suggested by Thomas.
Operation worked perfectly well, but: the A/C doesn't cool. Compressor cycles on and off as it should but air temperature at outlets is merely colder as outside temp.
Every time the system activated the compressor the engine RPM drop significantly, at a point the engine even stopped. So the compressor runs very sluggish.

I checked the refrigerant hoses:
- hight pressure line is hot at the compressor
- Low pressure line is NOT cool after condenser (as I'd expect it to be)

No error codes in the A/C diagnose function.

Any guess what might wrong? I don't know whether or not the A/C was operative before as European customs require all R12 refrigerant to be drawn and recycled for newly imported cars. So maybe the orifice is stuck?
What can I test now? I'm terribly lost when it comes to A/C stuff...

[jss06c6]

Did you change the orifice tube?? Mine had contamination and some metal shavings in it.

What are your high and low side pressures and what is your ambient temp when you capture these pressures?

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[Matt B]

Orifice no. I have a spare on hand so maybe that's the next step. I wanted to avoid swapping out any parts and keep it simple - didn't work :D
I didn't measure the pressures. Where do I take them? Low side at the accumulator/dryer, high side on the line next to the right front wheel?

I'll do more troubleshooting tomorrow. Really strange that it doesn't cool at all...

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[mhobtr]

Did you drain all of the old oil from the system?

[1991 Corvette ZR-1]

Good thread. Glad this was brought back up as my AC is basically blowing room temp and during the hotter months, I only drive it in the early hours of the morning here in sunny Florida. Not sure if the conversion has been done on my 91 but the condenser is in rough shape. I think this might be a winter project for me. A complete overhaul and replacement of everything possible. Looks like I have some reading and researching to do.

[jss06c6]

Orifice no. I have a spare on hand so maybe that's the next step. I wanted to avoid swapping out any parts and keep it simple - didn't work :D
I didn't measure the pressures. Where do I take them? Low side at the accumulator/dryer, high side on the line next to the right front wheel?

I'll do more troubleshooting tomorrow. Really strange that it doesn't cool at all...

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[Matt B]

Thanks, I'll try to measure later today.

Did you drain all of the old oil from the system?Not all, just from the compressor and whatever was trapped in the old dryer. Then added oil as instructed by the manual.
Would excessive oil lead to a complete failure of the cooling performance?

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[Matt B]

One more thing, maybe it's an indication... When I got the car all R12 has been removed during import. As expected the compressor didn't run as low freon was detected. However, even at that time no "low freon detected" code was present und the A/C controller diagnostic mode. No idea why the compressor was shut off though no error war present.
It started running as soon as fresh r134 was charged.

I'll try to apply the error procedures outlined in the manual later today, yesterday I was trapped at home by a massive thunderstorm...

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[1991 Corvette ZR-1]

I wanted to post on this and get some feedback, as I realized the only time I can actually drive my ZR-1 and not be miserable is early morning here in Jacksonville during our seven months of summer without cold AC, so I have moved AC repair to the front of the line.

First, I am considering the following kit and I wanted to see if anyone has used this before:

https://www.buyautoparts.com/buynow/1991/Chevrolet/Corvette/A-C_Compressor_and_Components_Kit/60-81498_RN?src=pla&gclid=CjwKCAjw4KyJBhAbEiwAaAQbE7vHDcVx0EFvsmU1w2jV O9qzHXR00z-vew5r1GJ5g8Fvu8k2SILk6xoCMYwQAvD_BwE

It comes with an accumulator and orifice tube, but if anyone has a recommendation on a different orifice tube, I am open to it. My condenser is toast. It will need to be replaced. There appears to be a leak along with what looks like most of the fins rotting off. I have read C4 condensers do not use large enough expansion tubes for R134. Is this addressed with 95-96 condensers using R134 from the factory? Prices on condensers range from $90-$600 and I am curious to see who is using what part number with great results. Can anyone confirm if aftermarket condensers have larger expansion tubes?

I read earlier in this thread that proper compressor line hoses are not made for C4s using R134. In my research on this, several posters commented that our hoses are not barrier type hoses, which are required for R134 vs R12. So is this just a case of recharging the system every so often? I suppose if I am going through all of this, it would not hurt to consider replacing the evaporator.

Bringing up the rear, I found these on eBay, should be what I need but if I am off the mark let me know?

https://www.ebay.com/itm/194023388957?_trkparms=aid%3D1110006%26algo%3DHOME SPLICE.SIM%26ao%3D1%26asc%3D20190917065201%26meid% 3Da0269f94791e41fc8c2625bfef8a17e7%26pid%3D100935% 26rk%3D3%26rkt%3D12%26sd%3D255077899730%26itm%3D19 4023388957%26pmt%3D1%26noa%3D0%26pg%3D2332490%26al gv%3DSimplAMLv9PairwiseUnbiasedWebCpr08MlcGreedyV3 %26brand%3DUnbranded&_trksid=p2332490.c100935.m2460&amdata=cksum%3A194023388957a0269f94791e41fc8c2625b fef8a17e7%7Cenc%3AAQAGAAACEN3V%252BNxdPCQh9NxzSGtC IJHoowgNTVjSKZ9K99zMROzae2g7pIc33R6EsmDKoZdlddPkr9 OD56Dkzj2%252BP3o3hZW7ghgfyMqOmCOzGxwtP4IQ9%252Bdn vjTUGFmvH8DDpyoRuB%252FG%252B%252FZJa5CvpZrzzob8nq W0xkKKodm64IJD3Aj5qTFtUaXmPZ61Yqd9dZ0YSJ4zbVrKvpAD IUhm4Y4kfQrBuuhBOwcaNgyV4%252FkrNjV%252BJ%252B374y YeMSyZF0Q6ei7xtnrJyvYMTQTo0ynzjJy2%252BugqkLk6dcJu 9O90Nf%252BErF%252Bwfd%252Bqjpz11vrcWxQGa2CTRdId43 WeP%252F2pVKUTiBjFzIGX1TVHq8%252Bsg1m42%252BiJZrZ0 G72MSeWXElfMVdxuNBd7J2MuRgpAyiyPKIBpDtSp3Onw0HolZ4 b1ufMYf9CCm0HgIGNCop9LFbqgVNEeFaC%252BjpYC98bE0cL% 252FMKkifQaFiLUGi56ziUvvCyjxKcbvuvnYH0%252FxjfPmix KJTvnghS1afQyXCrz593nIUixRKsu3IYLeYPMBEALOR6wn7fgA cRfsW0UB5ArJ%252BVOhkZTnEqgf3ulbWQ5Z9ASRMDHMxVtSqC ppXhxigNPr5bVaBzvcLeqGBWuuhzNkkaHrVvrJSXQx5nyExw0c n8BP9wwP1pjI8n2ncDTjovK%252BlpAWDlIsv9CTEtyr78%252 Bon%252BVm7aUZgGzvFLFwtw%253D%253D%7Campid%3APL_CL K%7Cclp%3A2332490


I think that is it for now. Just trying to accumulate the parts. No pun intended.

[Subfixer]

All R12 hoses, evaporator, condenser and dryer have American standard threads on the couplings.
All R134 couplings are Metric. You can not mix the two system components.
Cheapest option is the conversion kit.
Most expensive is replacing everything with components from a 94-95 ZR-1. 94-95 hoses are virtually non-existent. Most hoses on the web are incorrectly made.
I replaced everything, but finding hoses that were correct took months of orders and returns.

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[-=Jeff=-]

The difference between the R12 and R134a condensers is that the R12 is a tube & fin while the R134 is parallel flow. Using the proper condenser will yield better cooling however there is not enough volume of air in our systems. Comparing my 1990 max fan speed to my 2016 charger max fan speed both blow 14mph out the vents, however the Charger has more volume. I will say my setup runs cool now and works well. I have a parallel flow condenser running R12. Barely any load on the motor so it will run at 210-212F in traffic on a 95F humid day

[1991 Corvette ZR-1]

All R12 hoses, evaporator, condenser and dryer have American standard threads on the couplings.
All R134 couplings are Metric. You can not mix the two system components.
Cheapest option is the conversion kit.
Most expensive is replacing everything with components from a 94-95 ZR-1. 94-95 hoses are virtually non-existent. Most hoses on the web are incorrectly made.
I replaced everything, but finding hoses that were correct took months of orders and returns.

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Good point on the standard vs metric. What a pain. So I see these but if it is too good to be true, it probably is

https://www.ecklerscorvette.com/1994-1995-corvette-hose-air-conditioning-compressor-main-hose-zr1-lt5-25-293833-1.html?utm_source=google&utm_medium=cpc&adpos=&scid=scplp25-293833-1&sc_intid=25-293833-1&gclsrc=aw.ds&gclid=CjwKCAjw4KyJBhAbEiwAaAQbE7RkMajmVH7GvpwNri6i MkXc0veU5tjjItxBeJ6QQLLh8HteYKFxexoC14EQAvD_BwE



https://www.ecklerscorvette.com/1994-1995-corvette-hose-air-conditioning-accumulator-to-evaporator-zr1-25-114246-1.html?utm_source=google&utm_medium=cpc&adpos=&scid=scplp25-114246-1&sc_intid=25-114246-1&gclsrc=aw.ds&gclid=CjwKCAjw4KyJBhAbEiwAaAQbE8VuyhfsNMIQbuiR7kPn GBtVRwYQJAwxZpur0N-tWf1iHJEc8UCHFxoCWYYQAvD_BwE

And then there is trusting that the accumulator supplied actually do have metric threads. Are the 95-96 condensers LT5 specific?

[Subfixer]

I believe the accumulator is 94-95 specific.

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[Subfixer]

The compressor hose is the one I had most trouble finding. The compressor is also R134 specific. The connection at the compressor end is different than the R12 version.
Only way to know is to order one and see. The sales people have no clue what to look for. If it's wrong, send it back.

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[Subfixer]

There is a third hose needed also. From evaporator to condenser.

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[1991 Corvette ZR-1]

Yeah, that sounds about right. It would be too easy to assume a non ZR-1 95-96 condenser could be a drop in.

[tgonyaw]

Mark Heibeck converted my stock 1991 system to R34 this spring. Has worked great so far. Just got back from Carlisle and the outside temps were 90 plus . No parts were changed that I know of.

[Matt B]

The one thing that is recommended to be changed after that long time of car life is the dryer/accumulator. Over time this things soaks up with moisture. You will notice that when you check the weight of an old versus a new unit. These dryers protect the system from moisture and are subject to wear.
However, the one in my 1970 Lincoln Mark III is 51 years old and the system still works... But you can't go wrong to renew this piece every now and then. They are cheap and it's a valuable maintenance, expecially "once you're in there".

Another recommendation I got (and followed) is to use PAO oil instead of PAG. There is mineral type oil in the system which will not dissolve in R-134 and therefore can't circulate through the system as intended. Completely removing it is possible but painstaking. PAG is supposed to not mix with the mineral oil left in the system but rather build up a sticky goo. I have to mention, however, that I got no evidence this will actually lead to issues, instead I got another recommendation from a valuable source to not change oil at all.
Anyway PAO oil addresses this as it actually (temporarily) mixes with mineral oil AND dissolves in R-134. I mixed two samples (mineral and PAO oil) myself and they immediately blend into one fluid. So with PAO oil you keep the mineral oil part of the system with no cleaning hazzle.

The metric vs. imperial issue is addressed by the R-12 to R-134 adapters. These threat on the OEM R-12 imperial fittings (should be 1/4 on low and 3/18 on high side) and provide a snap on port on the other end. These worked with no issues for my car. I just don't know if snap on is a European thing or global standard for R-134.

Cooling is great in my case as well, we had 85F recently (which is much here...) and even with the bubble top on it was very comfortable.

I followed post #6 & #16 of this highly valuable threat to adjust low side cut off pressure. Maybe that helps cooling effectiveness.

[1991 Corvette ZR-1]

Guys, I did not want to start a separate thread for the same information but wanted to check if anyone has run one of these? Mine is toast and the ones from the Corvette parts suppliers are $500 or so.

https://www.partsgeek.com/gbproducts/DC/3222-05720161.html?utm_source=google&utm_medium=ff&utm_content=DN&utm_campaign=PartsGeek+Google+Base&utm_term=1990-1993+Chevrolet+Corvette+A%2FC+Condenser+UAC+CN+430 6PFC+90-93+Chevrolet+A%2FC+Condenser+91+92&fp=pp&gbm=a&gclid=Cj0KCQjw7MGJBhD-ARIsAMZ0eeuu6wtMO_sFG8bO1owPIaqS6ZVYIPHX_4l1uVYlNd MbV0a8Bj7XuskaAvqpEALw_wcB

I have had good results with other spectra products. Curious if anyone has used this. It beats $500+ for the next available options.

[bowtiguy]

Guys, I did not want to start a separate thread for the same information but wanted to check if anyone has run one of these? Mine is toast and the ones from the Corvette parts suppliers are $500 or so.

https://www.partsgeek.com/gbproducts/DC/3222-05720161.html?utm_source=google&utm_medium=ff&utm_content=DN&utm_campaign=PartsGeek+Google+Base&utm_term=1990-1993+Chevrolet+Corvette+A%2FC+Condenser+UAC+CN+430 6PFC+90-93+Chevrolet+A%2FC+Condenser+91+92&fp=pp&gbm=a&gclid=Cj0KCQjw7MGJBhD-ARIsAMZ0eeuu6wtMO_sFG8bO1owPIaqS6ZVYIPHX_4l1uVYlNd MbV0a8Bj7XuskaAvqpEALw_wcB

I have had good results with other spectra products. Curious if anyone has used this. It beats $500+ for the next available options.

I have not run that unit from that supplier, but the ~$100 one from rock auto worked like a charm on my R12 91 NCRS car. I ordered the same one from rock auto (134a) to convert my current car over the winter. Some dealers wanted $500+ for a condensor. I cant imagine there is more than one supplier for these....

[1991 Corvette ZR-1]

I have not run that unit from that supplier, but the ~$100 one from rock auto worked like a charm on my R12 91 NCRS car. I ordered the same one from rock auto (134a) to convert my current car over the winter. Some dealers wanted $500+ for a condensor. I cant imagine there is more than one supplier for these....

Found it over on Parts Geek. A few bucks more but was in stock. Rock Auto has it but it?s listed a shipping delay because they needed to get it from the manufacturer first, then ship.

https://www.partsgeek.com/gbproducts/DC/3222-05720161.html?utm_source=google&utm_medium=ff&utm_content=DN&utm_campaign=PartsGeek+Google+Base&utm_term=1990-1993+Chevrolet+Corvette+A%2FC+Condenser+UAC+CN+430 6PFC+90-93+Chevrolet+A%2FC+Condenser+91+92&fp=pp&gbm=a&gclid=Cj0KCQjwssyJBhDXARIsAK98ITT7VEKT7S_7LJ0KbVAr tpVpRgT9LCod35uoGYWCL6vA58AiVEicEuAaAoKmEALw_wcB

I hesitated buying it because paranoia kicked in and thought what if the threads are not the same or the angle of the tubes are off. But for the price, I will see what it looks like. Worst case, I will just have to return it. I also picked up the drier/accumulator kit they had for a decent price.

https://www.partsgeek.com/catalog/1991/chevrolet/corvette/climate_control/a-fs-c_receiver_drier.html?brand=gpd&rp=a-fs-c_receiver_drier_kit

So if this condenser works like the original, I have to wonder what the extra $400 goes to on the condensers offered by suppliers like Ecklers. Both are probably made in the same factory.

[1991 Corvette ZR-1]

MattB recommended PAO 68 oil so I got some from the Super Cool brand. Then I found this with UV dye after the fact. Anyone running this? I hate that I did not look longer at the products, otherwise I would have got this with the dye in it for tracking leaks.

https://supercool.ac/product/pao-68-viscosity-synthetic-lubricant-with-uv-dye-quart/

[Matt B]

Sorry, I could have mentioned... But you can add some in case of a leak. The manufacturer recommends a certain percentage blend anyway instead of pure dye type oil (which however should work according to their website).

Sent from my SM-G991B using ZR-1 Net Registry mobile app (http://r.tapatalk.com/byo?rid=90383)

[1991 Corvette ZR-1]

Sorry, I could have mentioned... But you can add some in case of a leak. The manufacturer recommends a certain percentage blend anyway instead of pure dye type oil (which however should work according to their website).

Sent from my SM-G991B using ZR-1 Net Registry mobile app (http://r.tapatalk.com/byo?rid=90383)

Hi Matt, no worries as I did not think of it and I have seen it mentioned before adding the dye. I can pick some up no problem after the fact and add in. The condenser, accumulator and orifice tube are shipped. Also waiting for hi/low gauges and lines to show up along with vacuum pump. I picked up a few other little things. Pretty sure my system is completely flat as the air blowing out the vents is outside air temp and I have a decent leak off one of the condenser connections. Guess I will know when I hook up gauges to check.

[dredgeguy]

When I purchased my 92 Z in 2012 it had already been converted to R-134 but many in Wazoo still using R-12. I was at our local cars and coffee Sunday and this guy drives up and tapes up signs for R-12 for sale. I was the first to make a move and made a package deal for the whole lot. New sealed 30lb container plus 19 cans of R-12. Wazoo is now set for a long time. Was in the right place at the right time! After putting the goodies in my car must have been approached by a dozen guys asking me to sell them a few cans. Sorry but they are for my guys!