R12 with an LS compressor?
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Launching!
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R12 with an LS compressor? I would like to have AC in my 240SX. The problem is, the LS compressor is set up for R134a, and the 240SX has an R12 system. Unfortunately, NOBODY makes a parallel flow condenser for the S13 - I am basically stuck with having to use the stock serpentine condenser. And R134a just doesn’t work well with serpentine condensers. Is it possible to drain the oil from the LS compressor, flush and fill it with R12 mineral oil, and charge the system with R12?
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Last edited by StorminMatt; May 11, 2023 at 01:39 PM.
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From: Central Cal.
It isn’t illegal to use R12. It isn’t made anymore, so suoplies are limited to what remains. And you have to be a licensed tech to buy it from any kind of dealer. BUT, you can get R12 all over the place these days via private party sales. Because cars that use R12 are now 30+ years old, very few of them are still on the road. Consequently, demand is nil, prices are low, and many people who have it are just glad to be rid of it.
Launching!
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From: FL
I'd stay with 134a.
Back in the early 2000's I converted a few of my own vehicles. I found condensers that would fit at junkyards and just got the information from what vehicle they were in a bought new ones. Adapt hoses and metering devices as needed.
You don't even need to do it this way anymore because so many places sell custom or universal condensers.
And FWIW, I've known a few old guys hoarding small cans of r12. I found it somewhat amusing that they didn't realize a few had rusted, leaked and were empty.
Back in the early 2000's I converted a few of my own vehicles. I found condensers that would fit at junkyards and just got the information from what vehicle they were in a bought new ones. Adapt hoses and metering devices as needed.
You don't even need to do it this way anymore because so many places sell custom or universal condensers.
And FWIW, I've known a few old guys hoarding small cans of r12. I found it somewhat amusing that they didn't realize a few had rusted, leaked and were empty.
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From: Dade City, Fl.
I've done the r12 to 134a more than a couple times. Most cooled very well. Never changed the condensers only the dryers and expansion valve or orifice tube.
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From: Montgomery (Lake Conroe,) TX north of Houston
As others have said, you can use a non-parallel flow condenser with R134a. Not ideal but it will work and it can work very well.
Back around 2008, I converted my former 1991 Mustang GT from R12 to R134a. I kept the original OEM Ford condenser. The system cooled pretty well but it struggled at stoplights when the engine was at idle. This was with the original, mechanical. clutched cooling fan. After a short time of dealing with that, I finally upgraded to a Lincoln MK VIII electric fan which was a popular thing for Foxbody guys to do back then. Once I installed that big electric fan, it pulled so much air through my condenser that I was able to achieve 40 degree vent temps and my idle speed temps didn't rise like they did with the inferior mechanical fan.
Back around 2008, I converted my former 1991 Mustang GT from R12 to R134a. I kept the original OEM Ford condenser. The system cooled pretty well but it struggled at stoplights when the engine was at idle. This was with the original, mechanical. clutched cooling fan. After a short time of dealing with that, I finally upgraded to a Lincoln MK VIII electric fan which was a popular thing for Foxbody guys to do back then. Once I installed that big electric fan, it pulled so much air through my condenser that I was able to achieve 40 degree vent temps and my idle speed temps didn't rise like they did with the inferior mechanical fan.
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Launching!
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After a short time of dealing with that, I finally upgraded to a Lincoln MK VIII electric fan which was a popular thing for Foxbody guys to do back then. Once I installed that big electric fan, it pulled so much air through my condenser that I was able to achieve 40 degree vent temps and my idle speed temps didn't rise like they did with the inferior mechanical fan.
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From: Texas
You could also try R152 - canned air-duster spray. It is listed as an acceptable substitute for R134, and has been used by plenty of guys in R12 conversions.
Its characteristics are very similar to R12.
Just for the hell of it, I charged my 2013 F150 with it after I did some A/C work, and it cools just fine. I've been running it for about three years now, no complaints.
Its characteristics are very similar to R12.
Just for the hell of it, I charged my 2013 F150 with it after I did some A/C work, and it cools just fine. I've been running it for about three years now, no complaints.
Thread Starter
Launching!
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You could also try R152 - canned air-duster spray. It is listed as an acceptable substitute for R134, and has been used by plenty of guys in R12 conversions.
Its characteristics are very similar to R12.
Just for the hell of it, I charged my 2013 F150 with it after I did some A/C work, and it cools just fine. I've been running it for about three years now, no complaints.
Its characteristics are very similar to R12.
Just for the hell of it, I charged my 2013 F150 with it after I did some A/C work, and it cools just fine. I've been running it for about three years now, no complaints.
Don't put R12 in it.... I did that back in 2001 when I put the LS1 in my Nova on the advice of an old hot rodder. Did like you said, drained all the oil and put in mineral oil in it and it worked OK for a while, but never great. Hasn't worked in years now though, and the compressor sounds awful, so I'm sure I trashed the compressor doing it.