Does anybody here know what is generally involved with converting a R12 machine to 134A?
I think the fittings would need adapters and the oil in the compresror would need to be changed.
-Dan
I know that this is an older thread, but nobody replied, and there is still the possibility to help someone out....
Supposedly, the R134A molecule is smaller than the R12 molecule. That is why there is a different rubber recipe/ composition/ color of the O-Rings.
Also, there is a different A/C oil used. I can't remember the specifics, but I use PAG46.
So go through and Rinse the system with Non-chlorinated Brake-Clean, change all of the Black Rubber O-Rings to a Blue or Green (make sure and lubricate them with the new oil), change the hoses to R134A hoses (once again, because of the molecule size), change and rinse the Vacuum Pump oil with the new R134A stuff.
That is the "Basics" for a r12 to r134 conversion. I've done it to a number of trucks, tractors, cars and refrigerator compressors.
Maybe you have already done it, though.....
Good luck.....