jimq

The 2 different oils in R134 and R12 cant be mixed. You will need to pull a vaccum to flush the system if you do convert.

williamreinecke

Does pulling the vaccum get rid of the oil or do you have to remove and drain the compressor?

Smokin

It depends on who you talk to. Pulling the vacuum is really designed to "boil" the water vapor out of the system. I don't think that the vacuum would get all of the oil out. A purist would tell you that you would need to disassemble the system and clean it or use new parts. I would think that a small amount of a different type of oil would not harm things too much... But I'd still say why chance it? Stick with what it was designed for unless you pay for the conversion done by a reputable shop.

Just my .02

greenjt

I was told by a friend who is a GM Mastertech and has done a lot of these conversions that you can leave the old oil in but you do need to add the appropriate oil for the product you are using. Apparently each refridgerant works with and will pick up a distinctly different oil. So if you put one oil in on top of the other, the old oil will not get picked up (whatever that means) and the new one will. He said the proper way to do it is to get rid of the old oil but it won't hurt anything if you don't.

DarrylH

I had my system converted to R134 by Porsche last summer, trying to do the ecologically "right" thing, but I'd say it doesn't blow very cold (black on black car doesn't help!) The guys who did it say it's actually working well compared to some 964s they've done. If I had it to do over, I'd probably at least try the drop-in replacements first. If they work, great. If not, no big loss, go ahead and convert then.

springer3

Freeze 12 is a stop gap. Performance is not as good as R-12 or R-134a. Fix the leak, and convert. It is irresponsible to run a leaky system, and it is expensive and inconvenient as well. Fix it right, and enjoy trouble-free cooling for the next 5 - 10 years.

Jerry Garwick

I considered going to R134 and my independent Porsche mechanic talked me out of it. He said that it just does not cool as good as R 12 in our cars. First of all, get a pressure check from a good A/C shop. It does not have to be a Porsche garage. Get the leaks fixed. Converting to R 134 may be as expensive as recharging with R 12. If you have any R 12 remaining in your system, the shop will pump it back into your system after the leak check. After I had my system gone over, it has not lost any coolant in two years. I've tried to work on my systems over the years, and have come to the conclussion that the A/C shops really do know what they are doing (in contrast to me!)

BaysideC4

I disagree with springer3, it’s not a stop gap it’s a replacement. You don’t need to change the oil in the compressor and you don’t need to change the receiver dryer. We have cars that are going on 16 years old and though changing to R134 may be a “nice to have” it certainly isn’t necessary. You also can’t guarantee 5-10 year of trouble free AC when the car will be 20-25 years old. Our AC problems are only going to get worse as our cars age.

All I am saying is that if you have a minor leak it can be fixed inexpensively. Freeze 12 even has a “stop leak” additive. If you had major AC problems (i.e. compressor, line replacements, etc) I would say R134 should be installed, but if you problems are simple and a can a year can solve the problem ($5), why convert?

It seems that most people that went to Freeze 12 are happy, the R134 converts long for their R12.

FYI - Not affiliated with Freeze 12 or Sherco
Freeze 12

springer3

Propane works OK too, and it costs less than $0.50 per lb. For a $5 refill of the old barbecue tank, you can top up your leaky system for years!

The point is "cheap" and "works" ignore the reason no car maker is using Freeze-12 or any other so-called drop-in. Drop-ins have problems. R-134a won on merit. I am tired of non-scientific "testimonials" for alternatives that on technical merit are not as good or cost-effective. I say fix the leak, get R134a like almost all cars on the road, and stop saying Freeze-12 and other less than optimal refrigerants are "awesome". Freeze-12 is 80% R-134a, and will also "drop in" an R-134a system if you really think it works better than R-134a.

If you need to get by for a month or two, go for it. But if you plan to keep the car and preserve your resale value, get the leaks fixed, and get on a standard refrigerant that every AC repair shop knows how to deal with. Stop gap is the correct term.

Thanks in advance for letting me rant.

BaysideC4

Why are we having this conversation? I appreciate your opinion Springer3, but don't mislead anyone that reads this into thinking that its less than optimal, my car blows 42 degrees and gets as cold as my Cayenne. I'm done with my rant too. Thanks

craig001

If you want to do more research head over to www.griffiths.com. They are the folks that "Excellence" used on a 1988 A/C conversion and make the Kuehl system.