Has anyone had any luck or any problems converting their FJ60 AC from R12 to R134? Anything to watch out for?
FJ60 R134 conversion from R12 (16 Viewers)
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Evacuate, screw on the conversion fittings, and go to town. "Needing" to swap out every O-ring in the system is a myth
There is a charge amount difference between 12 and 134. IIRC, They hold roughly 1.7lbs of R12, the conversion for R134 is supposed to be about 75% of that. When I did mine last week, it was happiest with only 1lb of R134, so keep that in mind as well. Just don’t put the same amount of 134 in as 12 came out.
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Thank you both
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Yep, I’ve heard between 75%-85%.
DickM
SILVER Star
60 Air Conditioning
I'm fixin to purchase a Denso compressor, dryer, and expansion valve for roughly $250 as the old stuff in my 1987 FJ60 is shot. Just wanted to double check opinions here first as to weather this is a good plan/option.
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I don't know if it's a myth or not. However, I assume people are converting because their system doesn't work, which almost always means that they system has a leak. O-rings are about $3. In fact, none of the common replacement parts cost anything. I changed over my '95 FZJ80 since it had a leak and all the R12 leaked out. I did the o-rings, expansion valve (less than $10), conversion fittings, and dryer (also less than $10). rinsed the old mineral oil out, put PAG oil in, pulled a vacuum, and charged the system. Works well. Did I actually need to do those things? Maybe not. But all it cost me was some time and chances are it will run cooler and last longer than if I didn't. And it was pretty darn cheap.
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Changing out an O-ring that leaks is not the same as changing out every O-ring because the r134a is “different”. So yes, it is a myth
You'll want to add PAG 46 oil since the mineral oil used for R12 isn't circulated through the system by R134a.
Stay with the R12, if it's available. I've done the R134a conversion and it cools fine, but the R134 molecule is much smaller than the R12 and I find I have to add refrigerant every season because it seeps past connections not designed for it. I had a pro shop change out all seals and used a fresh Denso reman compressor and new dryer, etc ...
There's another thread about using a R12 alternative that may be for you ...
There's another thread about using a R12 alternative that may be for you ...
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This is just not true! The o-ring connections in a modern car are exactly the same type of o-ring connections on older vehicles. You have a leak somewhere, and it's not from every single connection
Yes, BUT -- Modern AC systems designed for R134a have triple-seals. Old R12 have single. Same kind of O-ring, just more of 'em... 
The guy at the AC shop showed me the difference, but I did the conversion anyway. I've checked for a leak with both UV and red dye. None. I plan to switch to Duracool or Envirosafe when time permits. The R134a cools very well. No reason not to switch to R134 since it's available everywhere (for now)... Just requires more maintenance, that's all. At least that's my experience with FJ60s.
The guy at the AC shop showed me the difference, but I did the conversion anyway. I've checked for a leak with both UV and red dye. None. I plan to switch to Duracool or Envirosafe when time permits. The R134a cools very well. No reason not to switch to R134 since it's available everywhere (for now)... Just requires more maintenance, that's all. At least that's my experience with FJ60s.
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Who ever adds things to the 60 series FAQ should add this document. I am in the process of doing this and found the Toyota TSB for converting. I figure if anyone knows how to do it right Toyota should.
Wow. That's great. Thanks for posting.
No they don’t, I’m an Infiniti tech and all of our A/C systems have one o-ring per line fitting.Yes, BUT -- Modern AC systems designed for R134a have triple-seals. Old R12 have single. Same kind of O-ring, just more of 'em...
The guy at the AC shop showed me the difference, but I did the conversion anyway. I've checked for a leak with both UV and red dye. None. I plan to switch to Duracool or Envirosafe when time permits. The R134a cools very well. No reason not to switch to R134 since it's available everywhere (for now)... Just requires more maintenance, that's all. At least that's my experience with FJ60s.
That's why I'd never buy and Infiniti. 
Kidding. My F150 only has single ones, too. I've seen early systems that have 3. I don't really care. I'm just relaying my experience. Owners will do whatever they want and usually it's the cheapest thing anyway
Kidding. My F150 only has single ones, too. I've seen early systems that have 3. I don't really care. I'm just relaying my experience. Owners will do whatever they want and usually it's the cheapest thing anyway
I totally agree that not every o-ring is leaking or has to be replaced. My thought is that they are all very old, I have the o-rings, and replacing them is not very hard. So why wouldn't I replace them?
Doesn't make sense to me. I did a R134a conversion in my '93 FZJ80 years ago and haven't added any refrigerant since. You have a leak.
Certainly possible I missed it. I have a new evaporator in the garage just in case .....
I plan to check again, thoroughly, before switching to one of the R12 alternatives.
I plan to check again, thoroughly, before switching to one of the R12 alternatives.
There is one significant difference between older and newer A/C systems. Where older systems used the typical threaded fittings on the hoses, newer systems have mainly gone to block or pad fittings which tend to be a more secure connection.
