I used 2 cans of enviro-safe w/ dye to charge my system and I was under the impression that it was compatible with the oil already in my system. What I was trying to avoid was not just wasting the r12, but also not leaking it to the environment once I was done with the leak detection.
I believe that I now know why the compressor didn't engage, but you can tell me if I'm wrong. Being a recent Mercedes owner, I forgot the meaning of some of the controls and had the climate control set on "non-cool" and not cool. Later today I'll try again, but my refrigerant my be all gone by then which leads me to believe that it may have leaked out from some other place than the compressor (ie. leak is fast). Is the orifice tube located behind the glove compartment and is it worth checking now?