Newer synthetic compressor oil compatibility with R12 Freon.

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Anyone know about using freon with newer synthetic compressor oil?

I’ve heard using R134 in older systems with freon need to be flushed to use synthetic oil. But I’ve never heard the reverse.

I want to use R12 because the expansion valve, evaporator and condenser are all sized for R12. My experience with R134 is that it doesn’t cool quite the same when used in the older systems.

I will be flushing the system and replacing the dryer and expansion valves as well as replacing the old R2 with a new Sanden.
 
Anyone know about using freon with newer synthetic compressor oil?

I’ve heard using R134 in older systems with freon need to be flushed to use synthetic oil. But I’ve never heard the reverse.

I want to use R12 because the expansion valve, evaporator and condenser are all sized for R12. My experience with R134 is that it doesn’t cool quite the same when used in the older systems.

I will be flushing the system and replacing the dryer and expansion valves as well as replacing the old R2 with a new Sanden.
I have used Esther oil for both R12 and R134a.
 
There's one type of oil that will work for either. It might be the one mentioned above. That's probably the safest option.
 
You definitely need to flush the old lines first. Will it work without doing it yes but not the best. Denatured alcohol then blows it out, assemble and vac it down to about 30 so any residual oil boils off. That checks for leaks plus also.
 
i'd say no , but the lube my uncle used was just mineral oil with r12 . and he was a factory rep for frigidaire and a dealer for them as well .
 
half the battle is finding out what kind of oil your new Sanden compressor comes loaded with....its the reason i reluctantly converted my camper to 134...didnt want to disassemble a brand new unit to clean out the oil...iirc whatever kind it came with wasn't the kind that would work with either r-12 or 134...since then i think i've read that you can get compressors from Classic Auto Air (Original Air Group) with either type of oil in them but dont know for sure
 
This is what you should use with R12. Four Seasons 59000 Four Seasons R12 Mineral Oils | Summit Racing As has been mentioned above, do not under any circumstances allow the two oils to mix. You'll have a miserable goo in your system. There are flushing kits available that force flush fluid through the system using an air compressor. Works great, but I had my entire system out of the car and easily "bench flush" individual components like evap, hoses, condenser, etc. But using this device does allow you to flush with most stuff hooked up with the exception of the compressor (of course). A/C Flush Kit Car Air Conditioner System Clean Canister Flushing Gun Tools Set | eBay


Incidentally, eBay no longer allows the sale of R12, just silly, useless "refrigerant recharge cold air" kits. Just last summer I easily bought a can of 12 for about $35.
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There is a YouTube video on how to take the rear head off of a Sanden and measure the oil and replace it along with a new head gasket.. I just picked four cans of R12 up at our big swap meet this last Sunday. $15.00 a can.
 
If needed I have a 35 lb can of r-12 I would sell in PA Pick up only. Weighs 33lbs on the scale.
 
I would never buy "new" cans of R12. Mexico banditos are draining the RI2 and are refiilling them with water.
 
There is a YouTube video on how to take the rear head off of a Sanden and measure the oil and replace it along with a new head gasket.. I just picked four cans of R12 up at our big swap meet this last Sunday. $15.00 a can.
And the FSM shows how to make a dipstick to measure the level in your RV2 compressor.

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I would never buy "new" cans of R12. Mexico banditos are draining the RI2 and are refiilling them with water.
Or, as I've heard, a mix of "whatever" refrigerants or propane (which works just fine:D).

I just bought a can of Igloo. I hope the banditos aren't counterfeiting 1975 price stickers!
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Ester based oil will work for both R-12 and R-134a. Ideally, as noted, the system should be flushed to get rid of any gunked up, contaminated oil. The Ester based oil is non reactive with most common refrigerants such as R-12 or R-134a. If you are going to disassemble the system, replace all of the black o-rings with the green high density ones so that if it becomes necessary to someday charge the system with R-134a it will be less likely to leak. R-134a is in the process of being phased out in favor of R-1234yf. As an R-12 substitute, R-12a can also be used. This is a blend of modified propane and butane. This mixture is flammable when exposed to electrical arcs or open flame.

Dave
 
R-1234yf is flammable. POE oil is cross compatible with R12, R134a and R1234yf but it must be kept moisture free as it will acidify inside the system.
 
I would not recommend charging your a/c with any flammable gas.

R-1234yf is flammable. POE oil is cross compatible with R12, R134a and R1234yf but it must be kept moisture free as it will acidify inside the system.

Guys, please don't start with the flammable gas argument that has been "Dead Horsed" on the Interweb for 15+ years. 12a works and works well. If someone chooses to use it, that same someone is quite aware that it's propane/butane. Let it be. It has nothing to do with the oil compatibility issue that we're discussing here.

And please, everyone....let's not bring up the Dead Horse of 24 gallons of gasoline we're hauling around either.

I think we can all agree that our old cars are deathtraps, period. I'm happy with driving a deathtrap!
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Guys, please don't start with the flammable gas argument that has been "Dead Horsed" on the Interweb for 15+ years. 12a works and works well. If someone chooses to use it, that same someone is quite aware that it's propane/butane. Let it be. It has nothing to do with the oil compatibility issue that we're discussing here.

And please, everyone....let's not bring up the Dead Horse of 24 gallons of gasoline we're hauling around either.

I think we can all agree that our old cars are deathtraps, period. I'm happy with driving a deathtrap!
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I’m not arguing anything. What I said is a fact, but I digress.

I do not think POE oil is worth the extra price over mineral oil, when a conversion is contemplated.

A good execution of a conversion will remove all contents of the system, oil, water, dirt and refrigerant.
 
Ester based oil will work for both R-12 and R-134a. Ideally, as noted, the system should be flushed to get rid of any gunked up, contaminated oil. The Ester based oil is non reactive with most common refrigerants such as R-12 or R-134a. If you are going to disassemble the system, replace all of the black o-rings with the green high density ones so that if it becomes necessary to someday charge the system with R-134a it will be less likely to leak. R-134a is in the process of being phased out in favor of R-1234yf. As an R-12 substitute, R-12a can also be used. This is a blend of modified propane and butane. This mixture is flammable when exposed to electrical arcs or open flame.

Dave
Dave, all good points. But here's my concern:

Guy uses mineral with 134. Next guy recharges with 134 that has an oil "refresh" in the can, as many do. Now you have mineral/ester goo.

In my case, I carefully considered the cheap 134 conversion, which supposedly had been done on my car (nothing worked), but who knows the actual oil situation. I flushed everything and started over with expensive 12 with mineral oil. Baselined correctly. 44 degrees at the center vent.

I went went 12/mineral because that's the best option with our "antiquated" condensers and evaps. When I tell the next owner that it's "all 12, period", at least that owner should know that any added PAG and/or 134&oil squirt kits will create the goo.

So in my regimented world, 12=mineral, 134=PAG.
 
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