The Stovebolt Site Forums The Shop Area General Truck Talk Vintage Air Freon Question

I'm thinking about adding air conditioning to my 72 p/u. Vintage Air has some nice looking units but they can be bought in R134 or R12. Whats the scoop on these types of freon? Whats the best one to get.

Air, who needs air,,,,,dont know but I would go with the newer stuff,,,,regards,,Fred

You would be better off going with R134. That is what all of the new cars use. R12 was basically outlawed in the early 90's because of it's effect on the atmosphere. Also R12 is very expensive if you can find it. R134 is plentiful and you can buy it over the counter.

yeah-what he said, BUT, r-134 isn't as cold, so new cars have a bigger condenser and evaporator than old stuff. also different size metering orifaces. i recommend the 134, but remember the condenser is not as big as the later model stuff, so ya gotta use a fan that can move more air, or just live with what you have. in a pickup there should be no problem at all, but in a suburban, well, consider adding 2 units.

Koolkar's right. There's a 10% difference in cooling capacity. R12 is still available, and the price seems to have stabilized. Importation of R12 is allowed, but companies can only import a set amount each year.

Some of the new refrigerants show promise. Search for "alternative refrigerants".

I'm getting ready to get the a/c on my 69 going, and still have a few cans of R-12 left.

Thanks for the replies. I thought the 134 was the best way to go but I just wanted to be sure. Man you need air conditioning in Florida! We only have about 30 cool days a year.

FLORIDA!!! i didn't see that. consider r-406a. it is a "drop in" replacement for r-12. that means it is compatable with r-12---not that you can mix it (legally) with r-12. it's properties are that it is much colder than r-12, and less is needed to charge the system. i buy a 20 lb. cylinder for about $162.00. beware of some folks who sell replacements, as some folks sell propane as a replacement. in "hotshot" brand and r-406, there is a minute amount of butane, but they are non flammable. i have serviced a few hundred vehicles with 406 with great success. i have also used 406 in refrigeration systems like big coolers, etc, and have had no complaints.

just an alternative food for thought.

Had the AC in my 72 PU converted from R12 to R134,works AOK.

I found a Vintage Air sure fit system for my truck using all the stock dash vent locations for $1095. Free shipping and I'll install it myself. Sounds like a reasonable deal.

Has anyone used one of those kits (I saw one at Advance Auto Parts) that has everything you need to convert an R-12 system over to R-134 for about $40? Got a '69 that doesn't blow too cold anymore and thinking about snagging one of those but wanted to see if anyone else had done it first.

A few years ago a Mr Goodwrench buddy of mine and I went through the '89 Suburban and converted it to R134. At the time Chevrolet was recommending a lot of new parts. I don't recall what all I bought, but we did it totally by the book. I seem to recall that a new condenser was the expensive piece. We had to totally evacuate the system and blow out all the lines too, because of some kind of incompatibility in the lubricants for the two types of systems.

Now my buddy tells me that GM has changed their tune and allows them to just evacuate the system, use some kind of dual purpose lubricant and shoot the R134 in there.

On the Suburban it was cheaper to fix the leak and upgrade the system than to shoot it full of R12 at whatever the price was at the time. We even replaced all the lines to the rear A/C from under the hood clear up to the rear unit itself.

I may have gotten a bigger condenser by going the expensive way, but I do not notice an appreciable difference in the cooling. I seem to recall spending something like $500 on the parts and freon, with a discount because my brother is a Chevy dealer.

Definately us the 134...cheap & plentyful the floursant dye makes finding most leaks easy too.
10 years ago the esters (universal oil) was not avaiable, still recommending only do retrofits when the compresser is replaced.

brad

Did I mention, my buddy is skeptical about just shooting the R-134 into the old system. He thinks it is asking for trouble. Also, I should check with him for the latest. It's been over a year since we talked about this.

If you're converting from R-12 to R-134a, you need to replace the expansion valve and the canister. You can leave the hoses and seals alone if you have no leaks. The old oil is left in, it will stay on the bottom, the new oil floats on top of it.

Also, don't get the cheapy kit that doesn't have it's own schrader valves. If the old valves are left in, the will leak sooner or later, and cannot be replaced. The fittings that you put on have a clear threadlocker on them (which can be removed with lacquer thinner) and cannot be removed without destroying the threads.

So, to convert you need to:
1. evacuate the system
2. replace the expansion valve and canister
3. repair any leaks
4. remove schrader valves, install new fittings
5. vacuum system check for leaks
6. Charge with R-134a. You will need to look up to see how much freon & oil to put in. Less R-134a is used than R-12, so this is critical. Buy your freon from a parts store, they can tell you how much is needed. Also, your pressure readings will be different.

10 years ago when I sold Auto parts you had to be Certified to Sell and Buy Freon ( at least in Michigan). We were selling Freon at almost $300 for 30lbs. Our service department had to account for every once of Freon every week. The last 1 lb cans that I sold were $15.99.