n_holman

My R12 AC failed after very good service last year. I bought the car a year ago rescuing it from 30 years in a garage. The AC was working but needed recharging and performed brilliantly last summer, even when towing our Airstream in near 100* heat. But the first warm weather this year....no cooling. I took it to a AC tech and he tells me that a seal and bushing in the clutch failed and released the R 12 coolant, He recommends converting to R 134. First I find the R 12 gives excellent cooling in the Olds and my Buick convertible.....10 years on the Buick. The potential deal breaker is the estimated repair and conversion is $800 - $1000. Is that unreasonable? Will I be pleased with R 134?


Thanks,
Neil

Koda

R134A is not the refrigerant R-12 is. I have a 72 Chevy converted to R-134A, and, although it DOES work, it does not freeze you out. It was converted in 02, and I had it recharged in 09 or so. It will leak down in an old system, so you will need a booster shot every ten years or so.

My performance, on a 100 degree day, on max, with hot air in the car, is 66 degree air coming out the vents. Given a couple rounds of recirc, I believe it could freeze you out, but nothing like the R-12 would.

My advice, if you can get R-12, keep it that way.

nsnarsk65cutlass

R12 is a thing of the past banned in 1993-4 do the retrofit to r134a the cost of r12 is not worth it.

banny

I would ask what exactly is being done to warrant the kind of money. 134a can work certainly better than 66 degrees but there are steps that need to be done. I would think that you could get a new compressor, drier and a recharge of r12 for less than what he is charging you.

MDchanic

If you have a good-working R12 system, I'd keep it.

You can certainly change the shaft seal yourself and refill they system with R12 for less than this guy would charge you to convert the system, including the purchase of a couple of tools to get the compressor apart.

Remember, R134 is now also considered to be a "bad" gas, and is also being phased out, so it, too, will be hard to get sooner or later.

If you DO get the system changed over, remember that you must, at the very least, get a new receiver/dryer, a new cross-flow condenser, and have the POA valve recalibrated, or it wil work like crap, like Koda's does.

- Eric

66-3X2 442

Nothing but R12 in an R12 system. I have yet to see a 134 conversion do it's job in a R12 system. The R12 system is not designed for the 134 gas and I've never seen a conversion work as well. 134 isn't cheap anymore and 12 is available for not much more. I know I'm going to hear about how somebody converted their car from 12 to 134 and it will freeze you out but I've never seen it work as well.

classicmuscle442

R134a is not being phased out, R12 will work better in original system because expansion valve is designed for it. You can still find R12 in small cans for decent prices, if compressor still engages or cycles one can should do it. For system to work correctly it needs to evacuated with vacuum pump and drier changed before charging if system is empty. System should have tag showing number of pounds needed for total recharge, two or three cans, suction line at compressor should sweat when charged correctly, caution is warranted with the high pressures involved, remember the large line is the low side of system that you add refrigerant in, some systems have sight glasses, just charge till bubbles clear.

70cutty

I agree with 66 3x2. After my ac took a crap spent $300 trying to fix it. Then conversion to r134 that costs almost $1000 and it works like crap. First 100* day and it just wouldn't do it. Going with Vintage Air system now. tired of throwing money on an ancient system. For $1500 i think it's well worth it. I spent that much trying to repair the original.

MDchanic

"• R-134a banned from autos in Europe in 2013"
"• R-134a “incentivized” out of use in autos in US in 2016"


"Europe is phasing out R134a... in the United States, the approved replacement is HFO-1234yf... while it will not be required until the 2017 model year, automakers can get greenhouse gas credits from the 2012 to 2016 model years by using it."

Kiss it goodbye. It will be as expensive as R12 soon enough.

- Eric

The Bug Man

Almost finished with my 71 442 project. Trying to stay original on everything. AC is one of the final items. It's a factory air car but the compressor clutch will not turn. I have pressure tested the rest of the system. Dryer and lines seem to be fine. I was going to just buy a new clutch assembly and install it, pull a vacuum and gas er up, but now you guys have me wondering if it's worth the effort to use the original set up or just go with a vintageair compressor. I have been told the new generation gas will leak out of an old system eventually no matter what you do. Any input on this would be greatly appreciated. Thanks

Koda

It's not a question of doing something right or wrong, the original systems don't have the pressure differential needed to make the phase changes of R134 work as well as R12 did.

When I had mine converted, it was a daily driver in college. I have a 30 pound container of R-12 ready for when my 442 needs some, and someday the Chevy might get converted back, but it works well enough as it is. Certainly not crap, like the man with the pink car says, but nowhere near as good as the original.

70cutty

All I can tell you is that I spent around $1300 on original A/C system and now I am spending another $1500 on vintage air. I wish I had known about it before I spent the money trying to fix the original. IMO it's not worth it, especially if it gets to/over 100 degrees where you live.
JMO

MDchanic

Actually, any gas you put in will leak out.
The factory spec said that one pound of leakage a year was normal for R12.

- Eric

Mikes442

When I restored our 1970 442 Indy Pace Car in 1997 I reused everything and replaced the filter and O rings and changed to 134. When we first used it, it would blow cold air but not keep you cool. I asked around and found out you can not over charge 134. So I took it back and it was over a little bit. We let some out to the correct reading and it would freeze you out.
We sold the car in 2001 so I don't know how it did after.

hookem horns

AC work is an expensive, slippery slope with lots of opinions on how to proceed. Did your AC guy pressure test with dye to confirm it just leaked at the compressor? If so, I would replace the compressor/clutch and keep R12 since the system was working recently. I would strongly consider aftermarket like Vintage Air before dumping over $1k on a R134 conversion unless you really want it to look stock under the hood. Modern systems are lots smaller and efficient leaving so much more room in the engine bay.

banny

Wow, there sure are a lot of opinions on the subject. I bet the OP is gonna be confused now. The factory system was designed for r12. Like I said earlier, to make it work correctly with 134a a few steps need to be made. The vintage air and classic auto air etc etc systems are not that "modern" as they are hyped up to be. Basically its just a plastic box with and evap and a heater core inside. It uses an expansion valve just like the factory setups. It uses a thermostat switch just like the oems used back decades ago. Not much modern there. I see the new ones use electronic servos. The sanden compressor has been around for a long time. barrier hoses and bead lock fittings are standard stuff now days. The parallel flow condenser standard also. To me they are not all they are hyped to be. Sure they have there place. If you have a non air car, don't like the factory look, or are going for more performance oriented, or just don't want to deal with going through your original setup, then I understand. If you aren't informed, you can end up dropping major coin and not get the results you expected. I got a 71 skylark for a customer down to 43-46 degrees on 134a but it was on a completely restored system. I did recalibrate the poa but he didn't go with a parallel flow condenser. The result was great when the car is moving and air is dissipating the heat on that factory style tube and fin condenser. But when the car is stopped or travelling at slow speeds, the high side pressure starts rising rapidly and as a result, the vent temps start going up. but in the end, I would suggest to the op to just stay with r12 if the system was working fine recently. To properly convert takes a little effort and more than just keeping it r12 since his system was operational before the compressor clutch issue. I don't claim to be an expert at this but I use to work for classic auto air and now I restore factory a/c systems for a living now

70cutty

I don't know anything about AC. I can only speak from my personal experience.
It really comes down to best bang for the buck.
To completely restore and convert the system would probably be about the same if not more as Vintage Air system. However vintage air will cool better and it looks better. Best bang for the buck IMO.

66-3X2 442

I think what makes the Vintage Air system attractive is it's simple,compact and relatively inexpensive compared to an OEM unit. I like the R12 systems because when they are right,they are right and cool with the best of them and I keep the factory look. It's to each his own when choosing what type system you want. I sent all of my A/C parts to Classic Air for cleaning,pressure testing,rebuilding etc. and I probably have less than what a Vintage Air system costs. It's was a easy choice for me. Now if you have a non A/C car,that's another jungle to deal with and the Vintage Air system is probably the way to go unless OEM is desired.

MDchanic

Since you don't know anything about A/C, I'm not sure that you can make this blanket statement.

A factory Frigidaire system in good condition, running R12 should cool at least as well as, if not better than, a VintageAir system.

- Eric

Fun71

I agree with this. Back in 2000 I was advised by our local AC shop (AAPAK) to use R12 as long as it was available, then think about switching when it was all gone (which it currently is not).

I just recently found that Sam's Club and AAPAK have 30 pound tanks of R134A for $80. AAPAK also sells 30 pound tanks of R12 for $1200, so it is a fair amount more. I bought a jug of R134 from Sam's Club last month so I have a supply for the newer vehicles.

Exactly. I was told that while it won't be "banned" it will be taxed very heavily to discourage its use.

So fellas, head out to Sam's Club and buy a 30 pound jug of R134A while you can.

http://www.samsclub.com/sams/johnsen...equestid=18753

70cutty

Eric, if you put it like that (edited) than yeah. But if you read in between those 2 sentences you will see I was referring to the restored and converted system. Like I said I paid $1300 to restore and convert mine. It cools ok when it's 85 not so good when it's 95 or more. For the same amount I can have newer technology that's gonna cool equally or better, look better and much more compact, I will take the new.

MDchanic

Just wanted to make clear to the listening audience that they are unlikely to get more cooling by swapping out a functional factory system for a FactoryAir system.

- Eric

Fun71

For what it's worth, my factory refreshed R12 AC system cools very well in our 110+ degree summers. It's not like a newer car but that is due to the fan not moving as much air as the newer vehicles. The vent temps are quite chilly, though.

banny

This thread has really sparked up debate. Don't want to hijack the thread but just thought to ask if you guys think it would be a good idea to have a cooling and heating section on the forum kinda like what's on team chevelle. I approached the mods about it and was told there has to be enough interest to warrant it. So what do you guys think?

dc2x4drvr

x2

MDchanic

I hate to say this, but since the Olds (and especially Cutlass) HVAC system is essentially identical to the one in the Chevelle, pretty much any question has already been answered over on Chevelles.com. Why duplicate it?

[flamesuit_on]

- Eric

andrewk94

I converted to 134A three years ago and the system works well. It takes a few minutes longer than the legacy R-12 but it works well. I paid $650.00 for the conversion and worth every penny when a NorthEast heat wave comes by.

Was advised that the conversions do not work if system if the old refrigerant is not completely removed. If you do not mind waiting 5 minutes longer to be cool, then the conversion is a good move.

brown7373

I was tired of spending big dollars every time my A/C crapped out on one of my older cars. So I bought an A/C manual (Haynes, I think) so I could learn a little about it. My 72 convertible blows air in the 30s, and has been doing that for almost 4 years. It is a factory system I converted to 134a, with a recalibrated POA, new expansion valve, new filter dryer and new O-rings. And, here is the big thing, it has a CROSSFLOW CONDENSER I bought from Classic Auto Air. I paid $299 for the cross flow, or parallel flow in July of 2010. The original condenser can not sufficiently cool the 134a refrigerant, especially at slow speeds in traffic or at traffic light. That is why the temperature at the vent goes up. The crossflow is designed to work with 134a and it made a major difference in vent temperatures. I live in south Florida.

Fun71

That's a very good point. I was in front of my vehicles one day and saw the difference between the Cutlass condenser and the '98 Jeep condenser, so I pulled out my ruler and measured the number of fins between the two. Going from memory here: the Cutlass has either 9 or 11 fins-per-inch and the Jeep has near 20 fins-per-inch (and an aluminum condenser) so it is much more efficient at dumping the heat from the refrigerant. I was thinking at the time how much better my AC would work in 110º temps if it had a better condenser.

oldjimh

R290 works very well in a R12 system. It's banned in most states because it's plain old propane, cheap and no EPA greenhouse tax.
And an evaporator leak could get exciting so it's not safe for the average consumer. Yet EPA is finding a lot of it in recycled Freon..

http://www.lindeus.com/internet.lg.l...e138_11493.pdf

66-3X2 442

You ain't gonna be oldjim for long using propane in an A/C system.

n_holman

Thanks for all of your opinions. It has helped me decide......sorta. This Ninety Eight is all original from the paint in so any changes I would like to keep 'original'. I know how well R12 works in this car and in my '71 Buick convertible. So for that reason I will try to keep using such. The AC guy tells me that the compressor bearing failed so the pulley wobbled leading to a seal leak. Also a hose will need to be replaced. I believe he told me that if I am to convert to R134 the drier/condenser would need to be replaced. I know nothing of the workings of AC so if I stay with the R12 what other work is needed. He did say that the estimate would be about the same for either. That does not make too much sense. I've always done much of my own repairs but not AC. So I haven't got many different 'shop' recommendations from friends. The shop I chose has done minor repairs for me before and they are a long time local business.


Neil

66-3X2 442

The A6 OEM compressors really don't have a 'seal'. They use a ceramic type seal that uses the compressor oil to seal it from leakage. That's why cranking and turning on the compressor every month is very important in these cars,even in the winter time. The oil drains off the ceramic seal and lets the gas escape. An indicator of oil seepage is,it will stay moist with oil around the compressor clutch area. They actually make a felt washer you can put behind the clutch to keep the oil from slinging everywhere. At least that's what my buddy says who has been working on A/C systems for over 40 years.

jag1886

Your air guy doesn't know dick, it will cost less to repair what you have than to have it converted to R134 and not have it be as cold at it's best as a R12 system at 3/4 power.
My car had been converted to R134 when I got it and it was bad, had it changed back and it works perfect.
It also costs a lot of cash to convert it properly. You have to change out the valving, have the entire system flushed to get the old oil out (R134 and R12 use different oil), change the receiver dryer (you can't get all the oil out of it), and you may need to change the hoses as R134 runs at higher pressures than R12 and can leak through the hoses or can cause a blow out.

Fun71

If the all the R12 has leaked out of the system, then you can easily do the work yourself. It's just basic remove and replace components at that point.

Replace the compressor, remove all the line connections and replace the o-rings with new ones, maybe replace the drier (not always necessary, especially if the system hasn't been open for long), replace the schrader valves, and if you can get access to a vacuum pump, pull a vacuum on it. After that, bring it to a shop and have them add R12. If you couldn't find a vacuum pump the shop can do that for you as well.

That is another reason why it was recommended that I stay with R12 - the pressures that R134 reaches in the Phoenix summer heat would be high enough to cause front seal failure. The literature I read back then recommended adding an auxiliary cooling fan to vehicles that would operate in high temperature environments to keep the system pressure within safe operating limits. It seems I remember that 300+ psi was possible with our summer temps.

MDchanic

There are leaks, and there are "leaks..."



Access? I believe I've seen them at O'Reilly's for $20. MAW have one for the next time you need it.



No problem. If I recall, the safety valve is set to blow somewhere just under 500psi.

But, yeah, I basically completely agree with you - heck, he can get a rebuilt compressor, or a junkyard model, and just swap it out. And a new receiver's no big deal, everyone has them.

- Eric

hookem horns

X2, just bolt it up yourself and use a different shop to recharge. You are lucky that the original system is in good shape and recently operational, making this a very viable option.

My earlier comments may not have been clear. I was suggesting aftermarket if the original system was incomplete, in very bad shape and/or unused for years (very common like my car). I would not pump >$1k into a questionable factory system unless originality is important, since aftermarket will be all new and designed for R134. Big side benefit is a cleaned up engine bay.

My biggest issue with cooling (now Vintage Air) in my 69 Cutlass is the factory dash duct placement/design kinda sucks, regardless of how cold it blows. That and my crappy top & seals that need to be replaced...

cjsdad

I worked in an automotive A/C shop in Phoenix back in '91-'92 and the conversions to 134a were in their infancy. There was a lot of experimentation going on in our shop and we were able to get good results with the conversions. The 134a systems do operate at higher pressure levels, but not high enough to rupture hoses when working correctly. The molecules in the 134a refrigerant are smaller than R12 and that is why barrier hoses are needed. Pressures in the 134a systems will spike quite dramatically if the condenser doesn't get enough air through it. As mentioned earlier, the expansion valve needs to be calibrated for one refrigerant or the other as it will not work correctly for both. The compressor oil is different for each system so it needs to be flushed and freshly added when converting.

So the secrets to a successful 134a system is to have a crossflow condenser with adequate air flow. You must have a properly working fan clutch, a well fitting fan shroud, and the condenser sealed to the front of the radiator. Early thought was that the hoses needed to be retrofitted to contain the smaller molecules but later experience has shown that oil saturation of the hoses is sufficient to seal them. All the same, newer barrier hoses will provide a greater level of reliability. New HSN ( Highly Saturated Nitrile) o-rings and schrader valves should also be added, again for reliability. If converting to 134 the expansion valve should be re-calibrated or replaced. As mentioned earlier, the receiver/dryer should also be replaced to purge the system of any oil cross-contamination. The compressors are serviceable if they are in good shape.

Once the system is retrofitted it can be made to look exactly the same as the factory original system. The R-134a refrigerant is only slightly less efficient at heat transfer as the R12 so all things being equal the A/C system will work well, even in Phoenix. Great care should be used when charging the system with R-134a if a factory volume is not listed. Over charging will result is lower efficiency and cooling as well as much higher and damaging system pressures. The correct way to adjust the system charge is by monitoring the high and low pressure sides of the system along with the air temperature entering the condenser.

MDchanic

Sorry.

R-134a is a molecule with two carbon atoms attached to each other, with four fluorines and two hydrogens attached to them.
Its diameter is 5.24Å.

R-12, with only one carbon, two fluorines, and two chlorines is smaller.
Its diameter is 5.09Å.

R-12 weighs more at 120.91, versus R-134 at 102.03, so R-12 is heavier (because those chlorines are heavier than those hydrogens), but that has nothing to do with what you're saying.

The reason for the nylon barrier layer being placed closest to the inside of the hose, rather than sandwiched in the middle of the rubber, as it was earlier, is because the PAG oil that is required with R134a degrades the rubber over time, and would wreck the hoses before the projected service life of the vehicle was over.
It has nothing to do with the sizes of the respective molecules.

- Eric

cjsdad

If that is the only thing I got wrong, then my memory is not as faulty yet as my wife claims!

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