The a/c in my 1977 450slc a/c was not functioning. There was a definite lack of refrigerant. No leak die was located. The previous owner had had the car repainted the month before I bought it and it was suggested that the freon was recovered before the paint job.
The system was fully charged with R-12 (with Leak dye). All was great but the gas escaped again. NO leak dye can be seen.
This time it was suggested that the seals may have dried out a bit after the system was discharged, So the car had spent more time under a vacuum to make sure there were no glaring leaks and no moisture, Seal conditioner was introduced as were drying agents and a full charge of R-12.
That was about two months ago. The a/c was blowing cold enough to hurt if you had your hand near the vent.
Today No a/c. The compressor is running and there is a reduction of humidity out of the vents but obviously not enough gas to cool. No dye can be seen.
There was no warning. Either time. The a/c was producing ICE cold air one day and then nothing the next. No decrease in cooling was noticed either time. It worked great when I shut the car off and then it put out nothing after sitting a day or two.
The first charge lasted only a few weeks. This last charge a few months. Don't have to mention that a.c. work is pricey, and R-12 is outragous. I am way over buget on car repairs now so i am hoping that I can trouble shoot this myself.
Is there any component that could allow a sudden decompression of the system? This does not appear to be a slow leak. No decrease in cooling was noticed. I am hoping I can replace suspect components before I take it back for service. But again this stuff is not cheap so I dont want to just replace things blindly. And being a 30 year old sysem I want to mess with it as little as possible.
Any input would be welcomed. Going without a/c here is out of the question. Should mention. I've tried to clean the window on the receiver/dryer, It had paint overspray on it. I might be nuts but I think that the paint is on the INSIDE of the glass. Is that possible? What then?
Thanks all.