190E A/C question
 

Yesterday I added a bit of R12 to my A/C system, the first since I bought it 6 years ago. At the time, the pressures were 12 & 120 psi at about 90F. I added 14 oz of R12, it cooled well, just like it should. The pressures were at ~ 43 & 265. I drove it awhile, and now I get no cooling. The pressures are still the same, 40 & 260 psi, and the high side line is very hot. The low side line is ambient temp. The compressor seems to be working, as the pressures are OK, but I'm a little baffled as to the low side. It seems that the expansion valve is not working. If that were the case though, the pressures seem as if they would be different. Any thoughts? When I charged it, I didn't think about bleeding the hoses on the manifold gauges. Air, dirt? I don't think I overcharged it, but maybe.
Appreciate any thoughts.
Thanks!