Stick with R12 or not?

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Stick with R12 or not?

Postby LTDScott » Tue May 16, 2017 7:50 pm

Last year I replaced most of the AC system in my car ('85 Ford LTD but everything under the hood is from a '93 Mustang GT). I got a Ranshu reman compressor (new 6P148s are not available), new drier, new hoses, new seals, and a new parallel flow condenser. I flushed out the evaporator. I'm running a Contour dual electric fan set up on a DCC variable speed controller, with the cycling switch triggering the fan.

I found some old stock R12 so I filled the system to spec with ester (not mineral) oil. I took it to a local shop and they vacuumed the system and charged it for me. It worked great for a couple of days but I don't drive the car often, and soon after I found the compressor had an oil leak. It would visibly drip oil from the body of the compressor, down the front accessory brackets, and onto the ground. I confirmed it with a UV leak detector, and then wrapped rags around it to act like a "diaper" and the leak stopped. I stopped using the system to prevent the compressor from seizing, and unplugged the clutch connector.

Now I'm trying to get it working again. I took it to a shop and they evacuated the system and recovered about 12 oz of R12. I originally wanted to stick with R12 because it generally cools better on older cars, but I've heard positive reports that these cars do okay with R134 if you use a more efficient condenser like mine. Given the lack of availability and serviceability of R12 (the shop that did the work last time no longer deals with it), I'm okay with it being a few degrees less cold.

Either way I need a new compressor, but one appealing point for sticking with R12 is that I shouldn't need a new drier. There's no internal damage to the system, and I'll cap it off immediately to prevent moisture from getting in. I wouldn't need to flush either, although it's hard to determine how much oil is still left in the system.

What would you do here? Any other advice to offer? Thanks!!
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Re: Stick with R12 or not?

Postby Cusser » Wed May 17, 2017 8:41 am

Stay R-12, that's what I still use in my 1988 truck. New compressor to fix the leak. Can replace drier if you feel necessary, depends how long zero refrigerant is in the system.

Yes, I still have my own stash of R-12 cans, but several shops here in Phoenix still do R-12. My R-12 gauge set has adapter hoses that I use for R134a when needed.

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