What Route Do I Take With Factory Air

Discussion in 'The Big Chill' started by JoRion, Aug 17, 2022.

  1. JoRion

    JoRion Well-Known Member

    Hey All,

    I have a 72 350 with factory air, and for a long while I have been trying to decide what to do. I’ve been using the car as a daily driver for the better part of 2 years, and rolling down the windows was good enough. But California has been getting hot - been around 100 for the last couple weeks.

    I wired the AC back up a month or so ago - wiring was incomplete when I got the car. I tapped the Schaefer valve and the system clearly had some stuff still in there - and when on, the thermal limiter fuse doesn’t blow. So I figure there must be enough r12 in the system not to blow the fuse, but not enough to blow cold air through the vents.

    So, I’m asking what is the best way forward.

    Do I get an expensive can of R12 and put it in? Should I test vacuum on the system on the system first? If so, can I get some conversion fittings to use with a new manifold?

    I would reckon that the best move is to evacuate the system and rebuild the compressor with a double lip seal - but then I’d have to track down nearly 4 pounds of r12, or convert to r134. Keep in mind - I’m in California, so some things are easier said than done.

    I have read about converting to r134. It doesn’t appear to be a hard task.

    I’m trying to make this work without spending vintage air prices. I can do something like that down the line, but what should I do on a budget? Put some more r12 in and bet that the existing Freon leaked from the non barrier hoses?

    I know everyone will have a drastically different opinion, but I’m curious.
     
  2. 69WILD

    69WILD Ron

  3. SteeveeDee

    SteeveeDee Orange Acres

    I seem to recall that there are products now that "replace" R12 and can be used in our old systems. I have a 30 Lb tank of R12 that is nearly empty, so I'll be looking harder at solutions, in a couple of years.

    And, yeah, what he said. Got ninja'd.
     
    69WILD likes this.
  4. Redmanf1

    Redmanf1 Gold Level Contributor

    If your system is closed, I would get what 69wild posted and try it. If it has pressure the leak could not be that bad, as you have had the car for a while.
     
  5. WayneNJ

    WayneNJ Well-Known Member

    Following as I'm in a similar situation. 71 350. Factory air. 57k. All pieces there in good shape. Compressor turns on and somewhat cold air comes out of bottom vent. Have to replace vacuum canister. Blower goes from low to high. Right now cruse with windows down. A.c. not at top of my list but beginning to think of conversion to 134 or trying to maintain as is.
     
  6. FLGS400

    FLGS400 Gold Level Contributor

  7. PCUB

    PCUB PCUB

    I had my 71 350 converted to 134; the mechanic checked the system and it was holding pressure. Since then I have had to get the car topped off about every 2 years as the old compressor seals do tend to throw the 134 refrigerant a little more (splatter).
    All in all I am satisfied without the expensive compressor rebuild or change and it works (stays cool) for car used in hobby only.
     
  8. JoRion

    JoRion Well-Known Member

    mice had the car nearly 3 years, and know it sat for 4 years prior. And don’t think anyone has tinkered with the ac for a long time.

    I am hesitant to try the r12a because it made from propane. Have read mixed things about it.
     
  9. JoRion

    JoRion Well-Known Member


    That’s interesting. That’s what I was thinking. System holds pressure. So it could work out well.

    so you didn’t upgrade the ceramic seal in the compressor? Did you or the mechanic upgrade any of the components - expansion valve or poa?

    it appears to be a rather simple and relatively inexpensive process. Possible rebuild the compressor. Then change the dryer.adjust valves…
     
  10. Mart

    Mart Gold level member

    Anyone know exactly what and how many seals need to be replaced in compressor, hoses & all or any other connection fitting seals?

    I also picked up 4 cans of R12 & 2 cans of refrigerant oil that I should get going on...

    Larry, did you get your A/C working yet?
     
  11. PCUB

    PCUB PCUB

    Other than the 134 port change; no other component changes. In my situation, the mechanic checked everything before and after and said it was holding pressure and temp per his guidelines. I'm sure you can reasonably expect worn seals on the compressor due to age. In my part of the country AC is not depended upon year-round so your wear experience in your part of the country may be different. In my situation I decided to see how it performed and "roll the dice". :)
     
    Last edited: Aug 18, 2022
  12. Rod Kinkade

    Rod Kinkade Member

    To PROPERLY convert to R134a requires a different POA valve for proper pressures and a more efficient condenser which would have more and smaller tubes and more cooling fins. If done properly, it should be as good as the old R12. Your car has a sight glass in which you can see if it needs more freon or not. With A/C on it will either be clear (meaning it is either full or empty). But if you see foaming or bubbles, then you know it needs more freon.

    Many people who are satisfied with NOT doing these things typically do not live where it can get to 100-120F for most of the summer. Heck, if it is only 80-85F maybe simply replacing the fittings and installing R134a will be enough for them.
     
    69WILD likes this.
  13. JoRion

    JoRion Well-Known Member

    thanks for the response. I almost drove from Los Angeles to Northern California last week - it was 105 today.

    wound up not driving the Buick, but made me realize I need to figure ac out. As much fun as it is planning road trips like it’s the -1950s and trying to make it through the Mojave desert before sunup - I’d rather have ac.

    I’ll inspect my current setup my feeling is r12 will leak at a rate where it has to be topped off every year or every other year.

    134 will work fine with a recalibrated system and some new parts. It will be the next project.
     
    FLGS400 likes this.

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