SVX AC R134a conversion / recharge problem

[DavieGravy]

So I noticed that my AC compressor wasn't coming on any more.

 

That being the case, I did the R134a conversion and added a can of stop leak crap. After doing so, the compressor began to kick on again. I then added more regular R134a refridgerant until the guage needle got into the blue (full) zone. It only took a partial can.

 

The problem is it's not blowing cold air. Does anyone know why this might be? Do I need to add more refridgerant until it gets into the yellow (alert zone)?

 

Also, I never bothered to drain the system of the old R12 refridgerant. Could it be that having the 2 mixed is causing the issue?

 

Or, if R134a really sucks this bad I'll just buy some R12. However, I'd rather not go this route due to the high cost of this refridgerant.

 

I know that the general consensus is not to do the conversion because it ruins the compressor. However, If I'd have gone to the auto repair shop I'd have just gotten the run around and/or be out a few thousand bucks. Either way it was a no win situation.

[DavieGravy]

Nevermind, I apparantly didn't put enough in. I went by the site glass instead and added refridgerant until I didn't see any more bubbles. Hopefully the stop leak crap worked.

[subiemech85]

from the reading of your description:

 

YOU DID NOT CONVERT TO 134a

 

YOU RUINED GOOD R12

 

EXPECT PROBLEMS

 

converting to 134a is more than just installing port adapters

 

the oil is most likely not compatible with the 134a

 

pressure is relative to temperature

 

for good basic reference: http://www.celicatech.com/imagearchive/bgbonline/94_6gmanual/ac_system_general_servicing.pdf

 

for pressure and temp charts, etc. http://www.chillers.com/PT%20charts%20for%20refrigerants.htm

 

my '96 SVX with FACTORY 134a system works fine after I repaired it.

since the system was down to "no" pressure

 

1. use vacuum pump to hold vacuum at -23 for 10 minutes

2. with pump off, see if pressure goes to atsmospheric

3. if not, add 1 can of 134a.

4. if leaks are found, STOP and FIX the LEAK, most likely at the compressor head the o-rings go bad, then go to step 1.

5. continue filling, using the gauge set to see how the system is doing

[DavieGravy]

Yeah ok. I guess any alternative to spending thousands of dollars at some rip-off mechanic is bad.

[ericem]

As long as the system was not opened it should be fine and not need a vacuum, but ya r134a should not be mixed. Don't they sell R12A or R22A which is compatible with r12?? We have it here and on my old wagon I put the stop leak and the r12a or r22a can't remember which one, but it worked great for over a year with no leaks and it was the coldest it has ever been.

[subiemech85]

As long as the system was not opened it should be fine and not need a vacuum, FAIL the system has been contanimated by R134a and R12, which are NOT compatible but ya r134a should not be mixed. Don't they sell R12A or R22A which is compatible with r12?? FAIL R12 and R12a only share "R12", they are not compatible, and are not even close We have it here and on my old wagon I put the stop leak and the r12a or r22a can't remember which one, but it worked great for over a year with no leaks and it was the coldest it has ever been That may be, but R12a is not legal for automotive use in USA.

 

http://www.epa.gov/ozone/snap/refrigerants/hc-12a.html

Legal Status of HC-12a ®, DURACOOL 12a ®, and OZ-12 ®

 

HC-12a® and OZ-12® brand hydrocarbon refrigerant blends are flammable refrigerants. Their primary components are hydrocarbons, which are flammable substances such as propane and butane. HC-12a® and OZ-12® are registered trademarks of OZ Technology

 

 

Are there other refrigerants that can replace CFC-12?

Yes. Numerous other refrigerants have been found acceptable, subject to certain conditions on their use. EPA's fact sheet titled " Choosing and Using Alternative Refrigerants for Motor Vehicle Air Conditioning" lists these refrigerants and discusses the conditions. Lists of alternatives in other sectors are available online and from our hotline at 800-296-1996.

 

 

http://www.epa.gov/ozone/snap/refrigerants/lists/mvacs.html

Substitutes in Motor Vehicle Air Conditioners

 

NOTE: All substitutes in this sector are acceptable subject to use conditions. See SNAP Regulations for more information.

[capn_r]

1. use vacuum pump to hold vacuum at -23 for 10 minutes (in a subiemech85 post)

 

 

I'm confused, what units are used in a -23 vacuum? Are you referring to 23in HG?

[subiemech85]

yes, -23" of mercury

 

I use a "lab model" 0211 gast rotary vane lubricated pump, which is rated for -20"

 

basically use the Pressure and Boiling Points of Water chart to see how low you must go, basically do the best you can

 

it's been a few years since I went to school for AC

[DavieGravy]

I apologize for my last response on this. All the freon has leaked out and from what I can tell there's zero pressure in the system. I want to start by replacing the two gaskets on the compressor itself as well as the one that goes to the condensor. I was told by a mechanic that these are the most common leak zones. My question is, I've put the gauge on the low side and from what I can tell there's no pressure in he sytem. Is it safe to start undoing the bolts and so forth or are there other precautions I need to take? I know the pressure is really high in a charged AC system and I don't want this thing to blow up in my face.

 

Thanks

[ShawnW]

Thats still not fixing the problem for sure and adding freon to a system that may have a leak is just rediculous and not cheap either.

 

You need to put those seals on and put a vac on it and see if it holds vacuum. If it doesnt you aren't done yet.

 

People are doing this themselves thanks to the cans being sold in every store and single port installation kits. It makes me mad that people can just walk into a store, buy a can with a nozzle on it, and basically release it right into the air like its no big deal.

 

Whining about how much a professional charges to do it right is childish. Pick your battles. Fix what you are qualified to fix and leave the rest to the professionals with the right equipment to do it right. A $10 can doesn't give you a license to fix it yourself.

[Scoobywagon]

without the proper AC tools and machines, it is difficult to tell you what to expect. What gage(s) are you using? This is a job that gets MUCH easier when you have the nicer tools. A decent set of manifold gages is a MUST have. These will let you accurately and safely check pressures on both sides.

 

Having said that, lets see what we can do about getting you going....

 

If the low side shows no pressure, then you are probably fairly safe in venting that side. Leave it open for a while before you try opening the high side. Replace all of the o-rings you can find. If you added R-134A using the sight glass, you've likely severely over-filled the system. Should be 4-6 on the compressor, 2 each on the inlets and outlets of the evaporator core and condenser core, 2 each on the inlets and outlets of the reciever/drier. You'll want to replace the receiver/drier while you're at it. Think of it as $30 worth of really GOOD insurance. Make sure that you put a little oil on each of those o-rings. After you put everything back together, you really need to pull a vacuum on the system and make sure that it holds for at least 20-30 minutes. Now you can charge the system. The SVX's all call for 1.43lbs of R134A. You should probably also add about 2 oz of oil since you're replacing the receiver/drier. Having accomplished all of this, you should be able to run the A/C and get nice and chilly.

 

Good luck.

[DavieGravy]

Scoobywagon, thanks for the advice. Looks like I'll need to get some equipment if I attempt to do this.

 

Thats still not fixing the problem for sure and adding freon to a system that may have a leak is just rediculous and not cheap either.

 

You need to put those seals on and put a vac on it and see if it holds vacuum. If it doesnt you aren't done yet.

 

People are doing this themselves thanks to the cans being sold in every store and single port installation kits. It makes me mad that people can just walk into a store, buy a can with a nozzle on it, and basically release it right into the air like its no big deal.

 

Whining about how much a professional charges to do it right is childish. Pick your battles. Fix what you are qualified to fix and leave the rest to the professionals with the right equipment to do it right. A $10 can doesn't give you a license to fix it yourself.

Hey Shawn, I believe you've worked on my SVX before at Rick's. How much would you charge to do this for me?

 

David

Edited June 26, 2010 by DavieGravy

[Markus56]

Just want to put this out there, leaking R-12 into the atmosphere IS A FEDERAL OFFENSE punishable by a $25000 FINE and it is ILLEGAL to put refrigerant into a A/C system that is known to leak.

 

This is the ONE time you NEED to go an auto shop and have it PROFESSIONALLY fixed. You MUST be Section 609 certified to work on A/C systems.

 

 

 

 

[DavieGravy]

The R12 has long since leaked out on its own. I put in R134 (harmless to the environment), but it leaked out as well. I'm not responsible for Subaru's shortcomings. I never purposefully vented R12 into the atmosphere. So there's no need for you tree huggers to get your panties in a bunch.

Edited July 1, 2010 by DavieGravy

[DavieGravy]

MUST be Section 609 certified to work on A/C systems.

Total BS. If that were the case they wouldn't sell freon and guages at retail stores. I can fix the damn leak myself by replacing the gaskets in several spots. I was told so by a qualified mechanic. So take your overhead and $150/hr labor costs and whine somewhere else.

[Scoobywagon]

Actually, R134a is some fairly nasty stuff. Not at ALL harmless. But, for whatever reason, it IS on the EPA's list of acceptable refrigerants for automotive use.

 

Also, there is no requirement for any certification to work on an A/C system. There is IS a requirement for certification when buying refrigerant in quantity. They'll sell you the little cans all day long, but if you want the BIG can, you have to have a certification. If you want to buy a machine capable of recovering and recycling the refrigerant, you must have that cert. There is, however, no law requiring Joe Schmuckatelli to have any certifications AT ALL when working on his own car. Doing so for money is another story.

 

Markus is correct in that purposefully leaking refrigerant, whether R12 or R134a, is illegal and punishable by some stiff fines. The definition of purposefully leaking is generally accepted to include adding refrigerant to a system that is known to leak without also performing diagnostic or repair work.

 

Just to be perfectly clear on the matter, a leaking A/C system on a car that is AT LEAST 13 years old is simply part of the cost of ownership. Like all things, your A/C system requires periodic maintenance. Rubber hoses and seals develop leaks over time. Aluminum fittings corrode. That's just the way it is.

[Markus56]

Have you SEEN how big the hole in the ozone layer is? Cancer for everyone!

[DavieGravy]

Unlike the previously used R12, R134a dosen't destroy the ozone layer. That was a major contributing factor to the gubment mandated switch.

 

For informational purposes:

 

The leak in my SVX is coming from the front of the compressor. Upon closer inspection it was obvious due to the accumulation of oil on the belt cover and the front of the compressor itself. I also had a buddy with an SVX that exerienced the same thing. That's definately somethingto watch out for if AC problems are experienced on these vehicles.

 

Fortunately, ebay has proven to be a good source of used and rebuilt compressors for these cars.

 

Now for the love of God, no more lectures PLEASE!