I have a numbers maching 68 that is being done currently and nearing me making a decision about what to do with the AC, unfortunitly I my end up selling it after completion (2008 has not been good) but wondering what your thoughts are as far as effecting value. Thanks

You didn’t say what was currently wrong with the system. If all of the components are in working order, particularly the POA and compressor then you should stay with R-12. It is what the car was designed for and it will cool better with R12. R12 is also less likely to leak. R12 is expensive but so are replacing components and installing new service fittings for R134a.
Gary

Ive converted several cars/trucks over from R12 to R134 and they all seemed to cool better than with the R12.
The R12 is expensive and hard to get unless you are certified.
That being said I stocked up on 134a when you could no longer buy R12.

I don't think it will affect the value unless it is a 1000 point restoration of a high dollar car.

the fittings to convert it over are about 20 bux from a parts store. they just screw on old valves. you could fill it with r134 and than take fittings off. so it looks stock. nobody asks dont tell.

is'nt 134A universal meaning you can put it in a R12 system and get the same results.

Like some said above .. you screw some fittings on and when your done charging the system unscrew the fittings and no one would know the wiser.:cool:

the fittings to convert it over are about 20 bux from a parts store. they just screw on old valves. you could fill it with r134 and than take fittings off. so it looks stock. nobody asks dont tell.
Bill is exactly correct. Put in the 134A and remove the valves afterwards. There is NO reason to stay with R12. Even if you are doing 1,000,000 point inspection, no one will know. And if you tell them they should want the 134A. It works just as good and is much easier to get, less expensive and less of a problem for the Ozone. If you do sell the car, make sure you tell them that it has 134a. That would be wrong NOT to tell them.

By the way, the oils you put in the engine are not the same as they were in 1967 either. Who cares? Not said to be a smart a......, just a fact!

why dont you use a r12 replacement?

such as freeze 12..

http://freeze12.net/

Bill is exactly correct. Put in the 134A and remove the valves afterwards. There is NO reason to stay with R12. Even if you are doing 1,000,000 point inspection, no one will know. And if you tell them they should want the 134A. It works just as good and is much easier to get, less expensive and less of a problem for the Ozone. If you do sell the car, make sure you tell them that it has 134a. That would be wrong NOT to tell them.

By the way, the oils you put in the engine are not the same as they were in 1967 either. Who cares? Not said to be a smart a......, just a fact! before you go ruining something please read this .http://www.wikihow.com/Fix-Your-Car's-Air-Conditioner im certified and its true. Ive spent years dealing with ac of all kinds. i had the system restored in my 73 z28 10 years ago and pondered the switch but decided against it . what i decided to do is replace all components on the system but the 2 coils . all hoses, compressor, accumulator, poa valve, expansion valve , everything to ensure NO LEAKS. still has the same r 12 charge as when restored and cools fine. read the warnings. do it correctly and you will be happy with the r 12 results

I actually drop in a refrigerant called R409A, it acts just like 12. I can buy it because I am certified, and always have it on hand because I am in the commercial A/C and Refer business. There are many other drop is also, FR12, MP66, MP39, etc. They all act like 12, and work better with the mineral oils that are in our cars. The 134 gas really prefers an oil called polyolester, and the stuff absorbs water like mad. I will stick with my drop-ins Vs. the 134a, I like them much better, no special retrofit fitting or anything, and plenty cold.

http://www.actrol.com.au/techPapers/foraneR409Atp.pdf more reading and warnings

In no way is R134a as efficient as R12. Some of the blends are as good. Not all alternative refrigerants are suitable replacements to R12. This link is list of govt. approved replacements and there are many:
http://www.epa.gov/Ozone/snap/refrigerants/lists/mvacs.html
Whatever you use make sure it is clearly labeled (by law). Also be aware that you may have trouble getting a shop to work on the system. Most shops now have refrigerant identifiers so that if they connect up to a system and find a blended refrigerant in it, they may refuse to work on it or make it very expensive. Remember they have to capture what is in the system. Then what do they do with it? The government tells them they are supposed to ship it to certified recyclers for proper disposal.
Gary

Most commercial refrigerants efficiency are rated at 75deg (going off memory here)

Most automotive systems operate in a hotter enviroment than that. IF you compare on the same temp scale you will see that R22 and some of the other commercial gasses dont cut the mustard.

Freeze12 seems to be the best R12 "Drop-in" if you dont want to flush the mineral oil out of the system. I have family in Phx that use Freeze12 exclusivly and swear by it. If it can cool in Phx during the summer, well....

As far as converting to R134 I have done it many times at my shop. The thing you must do is dis-assemble the entire system and flush it to get ALL the mineral oil out. R134 WILL NOT carry this oil through the system and you will starve the compressor for oil, not to mention it takes up room which makes the system "smaller" and less effective.

R134 has its own oil and must be used if the system is to survive.

Some car's systems seem to take to 134 better than others, the condensor efficiency has alot to do with it.

As far as your car goes, you can drop in Freeze12 or convert to 134. Either way youll have A/C...


Chris:cool:

I actually drop in a refrigerant called R409A, it acts just like 12. I can buy it because I am certified, and always have it on hand because I am in the commercial A/C and Refer business. There are many other drop is also, FR12, MP66, MP39, etc. They all act like 12, and work better with the mineral oils that are in our cars. The 134 gas really prefers an oil called polyolester, and the stuff absorbs water like mad. I will stick with my drop-ins Vs. the 134a, I like them much better, no special retrofit fitting or anything, and plenty cold.

this is what i used in one of my novas......i wasnt sure if it was 409A or 408A i beleive it was called freeze 12? as i suggested in a previous post.

i have a 25lb can and can take a pic of it if anybody wishes...........

this is what i would reccomend.....

before you go ruining something please read this .http://www.wikihow.com/Fix-Your-Car's-Air-Conditioner im certified and its true. Ive spent years dealing with ac of all kinds. i had the system restored in my 73 z28 10 years ago and pondered the switch but decided against it . what i decided to do is replace all components on the system but the 2 coils . all hoses, compressor, accumulator, poa valve, expansion valve , everything to ensure NO LEAKS. still has the same r 12 charge as when restored and cools fine. read the warnings. do it correctly and you will be happy with the r 12 results
Mike,
You show your book knowledge and inexperience on working on A/C conversions. There is book knowledge, what the "professional" A/C guys tell you, and what is really true. When you work on them all the time you will learn that all the fears that are out there regarding the conversion are to make it so that YOU do not work on your car. Which is a good idea if you don't know what you are doing. Are there exceptions to the rule, of course.

Pull one of your A/C tech heads and ask him if all that you read on this is true. You will find he tells you it is bull s*****T.

I tell you what you can do, convert 100 of them and tell me how many problems you encounter. Then give me your expert opinion. I have done way over 500 conversions and been working on a/c and cars for 35 years.

I always suggest replacing any component that is bad and most of the time (as you know) that is most of them. I always suggest replacing the oil. Have done it many time without replacing the oil.

I don't think anyone said you will not be happy with R-12. Just a major pain today. Nothing wrong with using R12 if you want. To bad you did not do everything above and use the 134a. I would like to here about "ALL" the problems you had. LOL.

I have written articles on this before. A/C "fixes" are expensive, because a good a/c mechanic knows that if he does not replace all the a/c components like you did, he will be servicing it again and may end up doubling the costs. By doing what you did on yours, you make it so that it is done and over with. That is always the best way. But, don't knock the 134a conversion and realize that there is middle ground here that will cause no problems, or at least, very RARELY a problem.