I took my 85 wagon to a fairly reputable shop, where they told me that the schrader valve on the main froin AC pipe was somehow damaged and probably leaking.

The only recourse, I was told, was to buy a new pipe for around $350.
I was given the name of a guy who does custom AVC pipes on boats in Ft Lauderdale. They decided to never do any auto pipes again, for reasons that were unclear to me. So I bought the stupid pipe.

Later, I discovered that the same pipe was available online for under $200. Shops are concerned more with the prompt delivery of pipes to the shop and credit arrangements than reasonable prices. This is understandable. I have also found in the Miami phone book, shops that fabricate all sorts of AC pipes, I am guessing for less than $400.

The valve was not the source of the leak.

I was told that they sucked a vacuum overnight on the system and it had no leaks. This was untrue. It will hold gas for about a week.

Then I was told that it was all better again, but I needed a new aux. fan. Theis would cost about $400. I found a suitable replacement on e bay for $76. It is made in Taiwan, but it blows up a storm. I installed the fan myself, not a hard job at all. It did not blow. I jumped it from the battery, and it blew like mad. I fiddled with ice cube relays and other gizmos for a while, all to no avail. I told the shop owner that after $2000, I thought I should have a cold car, and he agreed, and asked me to bring it in to test it once more.

This time, the mechanic spotted that the aux fan fuse was made of molded plastic, not ceramic, and that it had melted to where it was not making sufficient contact. The metal strip on it was unbroken, so it tested ok with the test light.

This time, they loaded the system with dye and I drove about for one week. After four days, the AC stopped blowing cool. At the end of the week, the magical light and glasses revealed that there was a small leak in the compressor and a fairly large one in the evaporator, which, according to legend, never leaks on a W123.

I did not ask what these items might cost at the shop, lest I suffer an involuntary malfunction of my personal outrage system. I am planning to retire soon, and with my extra time, I plan to replace the parts myself. There seems to be adequate illustrated information on this website to do this. A good used vacuum pump will surely cost less than $100 per hour for 12 hours of removing the dashboard and replacing the evaporator. I am thinking about replacing the condenser with a new parallel flow type for greater efficiency as well.

I have been told by several people (some on this noble Forum) I trust, that R 134a normally will have some bubbles in the sight glass when charged properly.

One thought I had was that the 38ºF temperature on Dieselgiant's car was on a 123 model, and might have been done in cooler weather than you had on your 124. Of course, there is also a possibility that a 123 and a 124 have some sort of difference than would affect the result.

I also have a 1990 124 2.5 turbo, with a nonfunctioning AC, on which I have dumped about $2500 for perhaps three years of cool. I also want to get this one fixed, but I am leery of taking it to a shop for anything more than diagnosis, since the prices for parts are grotesque and labor is also a bit of a killer, when compared to my labor, which costs me nothing.

I long for the AC on the 1989 Hyundai Excel I once bought to avoid spending $400 for a month's rental while another car was getting fixed, which cost me one replacement hose and one recharge for under $150 in six years. The whole car cost me $250, and it ran for six, cool, albeit slow, years.

Good luck on cooler, cheaper air for us all. If we do not deserve it, I cannot think of who might.

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)