R12 Compressor Oil

[88MercWagon]

Dumb n00b question. Do our cars take an oil charge with the freon through the R12 port, or is there a separate place to add oil on the compressor? Thanks guys.

[Lincolnmania]

oil is added after a vacuum is pulled and before the charge, or in a small pressurized can of r12 and lube.....prob would not hurt to add a can of lube to the system if it's still r12

heres some, need a macs license to buy it tho

http://cgi.ebay.com/ebaymotors/R12-R-12-Refrigerant-12-Oil-Charge-/150622990854?pt=Motors_Car_Truck_Parts_Accessories&hash=item2311d47206

[86VickyLX]

When I did the R134a conversion, I just poured it in the compressor (removed the ports and poured it in). 4 oz in the compressor, 2 oz in the condensor, 2 in the evaporator. put system under vacuum to get rid of moisture, and charged it.

[alchemist]

At what state is your AC system right now? Did you lose charge and blow out some of the oil as well? If that happens, the best thing to do is to change over to R-134a. Evacuate all the freon, isolate the compressor and receiver/dryer by removing the lines from it (need to buy new fittings for everything you take apart), then run DuraFlush II through your evaporator core and lines, and condensor and lines. That flushes out all the old oil. Dump oil out of compressor and out of the receiver dryer as best as you can. Charge your receiver dryer with the correct amount of mineral oil that is spec'd for your application. Then put all back together, and pull vacuum for no less than 30 minutes. Verify that vacuum holds when you close off your system (never just turn off your vacuum pump without closing the system first). Then, with system still under vacuum, begin to add your refrigerant. Always best to add by weight and not use system pressures to 'guess' correct charge. That means you need to have your bottle of refrigerant on a good scale/balance and measure the weight loss over time.

remember on a receiver/dryer system, you add charge as gas. On an accumulator setup, you can add as a liquid (tank upside down). Always bleed (with refrigerant) all lines to prevent air from entering system.

I know this is overkill, but this is the best way to do it. If you just want to top off the oil, it's a guessing game, unless you are damn sure exactly how much you lost.

R-12 and R-22 require license (MVAC or HVAC).

R-134a does not. Sam's Club has great price on 134a cans and bulk 30lb. bottle.

[gadget73]

R12 is actually not much more expensive than 134. For a top-up on a basically working R12 system, its a lot cheaper to buy one can vs retrofitting it. It performs significantly better too.


Ive actually been reading about R414B as a replacement for R12. Supposedly it performs as well or slightly better than 12, and much better than R134a. I may do this with my car. The 134a works ok, but barely more than that. On a really hot day, it cools you off but it never gets good and cold like these cars do with native R12. The Mark VII also has wimpy AC, a known issue with R134a converted Fox cars due to their barely adequate AC condensor.


Another thing that actually really kicks ass as a refrigerant, though is generally a horribly bad idea to use is propane. Its flammable and smells like liquid ass if it leaks but it makes cold. Obviously this is NOT approved for mobile AC use.

[88MercWagon]

Alchemist: It's just weak, and the compressor cycles at speed. It was weak when I got the car 2 years ago, and I had a quick charge put in at a shop that still had R-12. It worked fine up until it started getting warm out this year. I bought a can of R-12 and a filler hose off of a friend, but I figured I would add some oil in too, since it seems that the compressor puts a larger drag than normal on the engine when it engages.

[alchemist]

Alchemist: It's just weak, and the compressor cycles at speed. It was weak when I got the car 2 years ago, and I had a quick charge put in at a shop that still had R-12. It worked fine up until it started getting warm out this year. I bought a can of R-12 and a filler hose off of a friend, but I figured I would add some oil in too, since it seems that the compressor puts a larger drag than normal on the engine when it engages.

Well, if you could get the R12 cheap from your friend at the shop, go for it. Unless you really think oil has escaped, then I wouldn't bother with the changeover. Yes, R-12 was (key word, was) a superior refrigerant. But make no mistake, R-12 is no longer made. All there is is old stock. If you can find it, most shops charge astronomical money for it. YOu shouldn't need to add in oil, unless you believe there was a catastrophic leak. Very little oil escapes in a slow leak.

[Lincolnmania]

r134a is no longer cheap either

[hypostang]

Well, if you could get the R12 cheap from your friend at the shop, go for it. Unless you really think oil has escaped, then I wouldn't bother with the changeover. Yes, R-12 was (key word, was) a superior refrigerant. But make no mistake, R-12 is no longer made. All there is is old stock. If you can find it, most shops charge astronomical money for it. YOu shouldn't need to add in oil, unless you believe there was a catastrophic leak. Very little oil escapes in a slow leak.

R12 is still made , just not here in the USA .. it is still used in Mexico as well as other places

[gadget73]

you can buy individual cans of it on ebay for not much more than R134a goes for. The cost-effective argument is largely invalid these days. The demand has also dropped pretty severely. Nothing has used it in a good 15+ years now.

[alchemist]

I'm with you. You can get R-12 offshore, for sure. I know a friend in Kentucky who ordered up some off of craigslist and the stuff that was in those cans was NOT R-12. Sorta like trusting the Chinese to make good baby food. Yeah, they can make a set of hand pliers that might last a few years, but they also put melamine in their baby food, as filler. You're also right on the demand part. But I stand by my statement that for old stock of stuff that was made here in the USA, it's pricey. Yeah, 134a is going up too. Why? Because in 2017, the good ol' EPA says that it will be phased out and substituted with another even more ozone-friendlier refrigerant. Dupont is working on that replacement. I stockpiled two 30lb. containers of 134a when Sams sold it for $60. Try to find it for that price now!

R22 is over $200 for 30lbs. and we probably won't see it go lower, ever. Time to stock up on it, for your home HVAC, if you have an older unit that still works.

btw, while in grad school, in 1993, I worked on 134a. We did extensive tox studies, using F-19 NMR, in rats to show that if they breathed an atmostphere containing the gas, it was completely metabolized (exhaled) by their lungs. We had the NMR method quantitated down to sub-ppb detection.