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    #16
    Flushed all of the components. Used the Four Seasons AC flush from NAPA. That stuff is pretty potent, flashes off quick and clean as well. Put a quart through the evaporator, almost 2 through the condenser (removed and sloshed around). Drained and refilled the compressor and pumped it while draining. Replaced the accummulator/drier and orifice tube along with both high and low fittings. Remembered to take the old schrader valves out of the r12 fittings before attaching the adapters this time.
    Used an orange orifice tube because that is what they had at the store when the previous one came out black and scongey
    When I was flushing the heat exchangers the flush came out black at first and there was black in the old orifice tube. I flushed until they came out clean and blew them through with compressed air, same process for the hoses, the discharge hose from the compressor was new and had not been contaminated even though it was already installed. Replaced the low pressure switch with one for r-134a as well, then charged with 7-8oz ester oil and charged to appropriate pressures with r-134a.
    AC blows nice and cold, now if I can sort out some of these vacuum leaks the ATC would work properly as well.
    1986 Country Squire
    1969 Mercury Cougar
    1960 Land Rover Series II 88"

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      #17
      Stock I think is blue, but I've occasionally seen it suggested to use the next size larger with 134a. Other people say it screws up everything and only the factory one can be used. I've never quite gotten a solid answer as to exactly what tube should be used and why. I know just enough about AC to put it back together and have it work but re-engineering the system is a little beyond me.
      86 Lincoln Town Car (Galactica).
      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

      91 Lincoln Mark VII LSC grandpa spec white and cranberry

      1984 Lincoln Continental TurboDiesel - rolls coal

      Originally posted by phayzer5
      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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        #18
        Orange was used with R12 and R134a systems. Blue was the older one. Orange has a smaller orifice. This may assist with the differential pressure that 134a requires to really get the chill on.

        Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
        rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
        Originally posted by gadget73
        ... and it should all work like magic and unicorns and stuff.
        Originally posted by dmccaig
        Overhead, some poor bastards are flying in airplanes.

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          #19
          As someone who has actually taken design classes on HVAC stuff, it's a fairly difficult system to change multiple components and have predictable results without running the numbers. I don't have the access to the software we used at school but all of these systems have to be solved numerically with a boat load of input data that we don't have. But in general, yes, R-134a needs higher working pressure differentials so a smaller orifice will help bring the temperatures down with the tradeoff of overall heat removal and compressor efficiency. AC systems like these are pretty basic to understand as a concept and general principles, but the math gets sticky when we start looking at real world efficiencies and losses.
          1986 Country Squire
          1969 Mercury Cougar
          1960 Land Rover Series II 88"

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            #20
            Also. A new style condenser goes a LONG way towards helping with R134a conversions. The original R12 condensers are not as efficient. My 93 worked okay with the R12 condenser, but works MUCH better with the newer style.

            Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
            rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
            Originally posted by gadget73
            ... and it should all work like magic and unicorns and stuff.
            Originally posted by dmccaig
            Overhead, some poor bastards are flying in airplanes.

            Comment


              #21
              I plan to change mine as they fail basically. The one big advantage to the old style condenser is they are much easier to clean. Parallel flow will just flush cleaner through open passages instead of forcing the trash out. Basically means you have to do a condenser if the compressor blows up.
              86 Lincoln Town Car (Galactica).
              5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

              91 Lincoln Mark VII LSC grandpa spec white and cranberry

              1984 Lincoln Continental TurboDiesel - rolls coal

              Originally posted by phayzer5
              I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

              Comment

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