Got my 73 charged up last summer, but it all leaked out again during a couple of months. Luckily we had put in some of that tracking substance in the system, and with them yellow funky glasses on holding the magic light, I could clearly see a leakage on the backside of the compressor (see red arrow on the pict). Behind of what seems to be the “Pressure relief valve” or possibly "Super heat switch" is a so called O-ring, and my question is where to get hold of these?
