Looking for advice, keeping r12 freon

[Kaysen]

I bought an 86 swb back in December and as its started getting warmer its time to get the A/C working. All components were said to be in good working order from the previous owner but he said it takes about a can of Freon a year bc of a leak. I've thought about swapping to 134a but after having several of these trucks and converting them all, I just don't think it works as well as the r12.

So heres what I'm thinking. save the money on converting it over and buy r12 instead (about 30 bucks a can from what I can tell, plus have someone with a license buy it). Have the system bled and any r12 Freon left in the system caught, then replace orifice tube and all O-rings to try to stop the leak(s). Then add more new r12 Freon.

Am I missing anything, like should I replace the dryer?? I have a friend who has all the proper r12 equipment to do it I just wanted to get another set of opinions before I pull the trigger on over a hundred bucks worth of freon. Thanks in advance. Kaysen

[Katrina/10]

It still has R12 in it now? I'd say add a can and try to find the leak before you take it apart and randomly replace stuff. If you open it up, you should always replace the accumulator, there is no dryer.

If you have a friend with refrigeration equipment he should be able to help also.

[Kaysen]

Yes it still has Freon in it, I started to poke the Schrader valve to see if it still had any pressure in the system but I haven't yet. I like the thought of drawing a vacuum on it and just adding a can of Freon plus some dye. Any suggestions on the best dye to use? I said dryer, but I meant the accumulator. I've heard it called both names so I wasn't sure which was correct.

So I guess all I need to know now is what is the best dye to use. I've heard of some kinds gunking up the system but I don't know how much truth is in it.

Thanks for the response

[Jeepwm69]

I put a can of R134 from Walmart with dye in my old Accord, used a $7 black light from Amazon, found a leaking hose fitting, replaced the hose, and was good to go.

I retrofitted my 85 Jeep CJ from R12 to R134. Easy to do, and cold as I could want. Looks a little more in depth on these trucks, but given the cost of a leak, I would switch over.

You could try this stuff

Amazon.com: Enviro-Safe R134a R12 Replacement AC...
The way I look at it, on a 30+ year old truck's AC, if you mess something up, it was probably not long for the world anyway.

Do let us know what you find. I need to fix the AC on my 83. I was planning on retrofitting to R134 on mine, but need to find out where it's leaking.

[Katrina/10]

I thought you meant it was only 1 can low. If you want to vacuum it, that will require a total discharge and recharge. That is a pretty good bit of money to throw at it with R12.

Personally, I could not tell much difference with R134, would just charge it with that and see what happens. 6.50 a can at Big Lots.

[neatoldstuff]

Your best bet is to change to 134A. Works better cools better. If you have it charged at a shop, legally they can't charge it without finding and repairing the leak. So, do it right and convert.

[Ziegelsteinfaust]

A cheap R12 replacement is R290. You probably have a tank of it lying around your house under your bbq.

I have done it in the past, and it practically is a direct replacement for R12. On the PT chart it has the same numbers. You should of seen my friends face when I was doing it, but it saved him $500 in parts to do a proper conversion. Especially when a hose cost $25 or so.

In the supply house's they also have some stuff that is a drop in replacement, but you have to buy a $100 jug. About 30 pounds of the stuff or enough to fill your truck 15 times.

[kalbert]

DO NOT put propane in your system. Its illegal, and puts you and everyone around you at risk. DO NOT. Worst advice ever.

Just convert to 134, it will be fine. You'll need a new drier, new seals, and to flush the system to do it right but doing it right will make it perform as good as it ever did with 12.

[Edahall]

Originally Posted by kalbert

DO NOT put propane in your system. Its illegal, and puts you and everyone around you at risk. DO NOT. Worst advice ever.

Just convert to 134, it will be fine. You'll need a new drier, new seals, and to flush the system to do it right but doing it right will make it perform as good as it ever did with 12.

To put things into perspective, the fuel in your gas tank is much more dangerous than the small amount of propane to charge your A/C system.

[tucsonjwt]

Stay with R12. Changing to 134A will require a new cross flow condensor and addition of a pusher fan if you want it to cool OK - even then it won't be as good as R12.

[Ziegelsteinfaust]

They used it in Europe for quite a few years in cars, and in appliances too. You can actually order R290 at parts house's if you want the actual version with flame inhibitors. It is not common over here for reasons I do not know.

Also all refrigerants commonly in use start with Propane, Butane, or Methane as a base material. Plus it makes up the vast majority of what is in the bottle. The new M1008 series is pretty much only in Europe now, and I do not know if is going to come to my side of the industry.

134a is nice if your system is like mine, and completely shot. If you have only one small issue it has an advantage. Or if you have several cars or friends who want to go in with you you can get an effective drop in R12 replacements at parts houses. You may want friends to go in with you because its $125 average for a 30 pound bottle. You just need to power flush your system with nitrogen, and a deep vacuum.

Also watch those 134A power cold or polar refrigerants. If you still have a leak after installation they loose effectiveness because they have a glide to them since they are a mixture of refrigerants. The 400 series in commercial refrigerants is the same effective thing. It is not like it won't work or cool the car, but it loose's some of its cooling efficiency.

[kalbert]

To put things in perspective, r290 and propane in your grill are not the same. R290 is not approved for use in motor vehicles. Do not use it.

Here is a link to some information you should know.
http://www.epa.gov/ozone/snap/refrig.../macssubs.html

There is no reason to use R12 anymore.

[Corts60]

As a refrigeration tech, I'm surprised at some of the responses I've heard on here. A few of them completely illegal and dangerous.

R12 is and will always be a better refrigerant than R134a. It is more efficient and it's boiling point is higher than R134a. However, it was discontinued because it is a CFC refrigerant, which is much worse for the environment when released into the atmosphere than R134a, which is an HFC. That is the short version of what I wanted to say.

Now, never ever mix two different types of refrigerants together. I don't care what anybody says on here. If you want to do your truck and your wallet right, just find the leak, repair it, and then convert to 134a properly.

[Kaysen]

After checking it over and finding an extremely noisy compressor, I'm going to replace the whole system and charge it with r12. The same friend gave me a reman delco compressor he's had on the shelf for prolly 20 years, is there any reason not to use this one? (Like dry seals etc).

[67RS/SSx2]

R12 is pretty expensive. I still run R12 in my 67 Camaro but nothing else. Check out a product called Freeze 12.

Some claim it can be added to R12 already in a system but I did not want to do that. I had a leak in the AC system on my 69 Camaro. I repaired the leaks but did not want to go back with R12. I did a lot of searching before settling on Freeze 12. I removed all R12, evacuated the system, then recharged with Freeze 12. I am happy with the results.

You can buy Freeze 12 in small cans...12 oz I think. I think I paid around $10 per can. Not cheap, but no too bad. I think I like it better than R134A unless you are going to change all component (condenser, evaporator expansion device, etc) to R134A.

[kalbert]

According to the EPA chart, Freeze 12 is 20% HCFC-142b and 80% HFC-134a. Make sure if your car is ever serviced by a professional that you mention this. They will need to recover it to a tank separate from their 134a or 12.

[bhc41051]

Don't waste your time and money converting to R-134A. Use Freezone (RB-276) It's a direct drop in for R12 and cools better than 134.

[kalbert]

Free zone is 19% 142b, 79% 134a, and 2% lubricant. There are no 'drop in' replacements for 12, you can not mix 12 with anything. You must recover all remaining 12 before putting something else in. Freezone must also be recovered separately, you can't store it in the same tank as 12 or 134a.

Also, being that the truck is an 86 and is getting a new compressor, it should also get a new orifice tube, drier and a flush to make sure the system is free of debris from the old compressor. O rings are cheap, and since the system will have been flushed empty you'll need to add the full amount of oil. There would be no reason to not use 134a at this point. Don't forget to straighten smushed fins on the condenser. Its very tedious, but proper airflow over it makes a significant difference.

People who complain about 134a not cooling as well as 12 generally have some other problem that wasn't addressed before they sucked the 12 out and put 134a in. Saturated dessecant, damaged orifice tube or stuck expansion valve, weak compressor, or smushed fins on the condenser.

[Kaysen]

I will be going with everything new on the system (compressor,condensor, orifice tube, and accumulator, and o-rings), I know I'm going to keep this truck for the long haul so I'd rather start fresh with everything new. That being said, I'm going to go ahead and go with r12 only bc of the better cooling properties and since that's the freon the system was originally designed to run. After searching craigslist I've found several people selling 12oz cans of r12 so I don't see any reason not to go this route, aside from the extra cost which isn't terrible in my opinion. I'm also going to buy a few extra cans while I'm at it in case I wind up needing some for in the future.

[andrewmp6]

I would find the leak fix it and keep it r12.r12 is colder and the system is designed for it so it will run better.

[bnoon]

A properly done 134 conversion will cool to within 1 degree of a 12 system at the center vents on these trucks... by my experience anyway. My 86 was ice cold.

[Kaysen]

I lucked out today and found a car guy who had 4 cans of r12. Needless to say I bought them without hesitation! Now I definitely know what route I'm going once I replace all of my ac components.

[RShook]

Any idea how much r12 freon these things hold if completely empty? I'll be putting mine together in a few months hopefully.
I have two 12oz cans and I'll need more but just curious as to how much more.
It's a 77 Silverado with original ac

Thanks for any info

[Kaysen]

In my 86 I was told 3 cans will do it, but keep in mind mine has the "pancake" compressor and yours may be the long kind.

Update a little more on my treasure chest of Freon finds. So not only did I find the four cans of r12, but I also found 1 can of r12 oil charge and 9 cans of freeze 12 oil charge. The price was right so I figured might as well. Then, at autozone I found a fill hose for 10 bucks! This all might sound like a bunch of nonsense to some but I've definitely enjoyed the time spent tracking this stuff down! lol