I decided that I will replace all the orings, orifice tube, and the shrader valves. Then vacuum down and recharge. The system has plenty of oil, and probably more than enough because the R134a we threw in it last summer had some oil charge in it. The receiver drier is also fine. My low side has a standard R134a connector, so replacing the shrader valve is no problem. But my high side has some freaky things going on with it.
Low side, with the normal cap/adapter:

High side, with what appears to be the original R12 fitting??

I am assuming that the high side has the R12 fitting. And the previous owners never put the r134a adapter on it? If so, does that old r12 fitting unscrew, and I just screw this new one in?
http://www.ebay.com/itm/R134a-High-Side ... e1&vxp=mtr
Also, should I replace the orings/seals for where the hoses connect to the compressor?
Thanks for any info in advance!


