Just finished a 3 to 4 week long episode of work on my 85 300D's AC system by charging it with 2.9 lbs of R12 with a digital fishing scale. The only parts replaced in the system were all o-rings, Schrader valves, TXV and receiver dryer and PAO 68 synthetic oil that is suppose to be superior to mineral oil. It is note worthy that I used all the original hoses as well as the old R4 compressor, evaporator and condenser, which were pressure tested and found to have no leaks.

This video https://www.youtube.com/watch?v=gAm8zPptXlM was taken on a 2 mile drive to Autozone to return the rental vacuum pump used to evacuate the system. It was 87F ambient, car was parked in the sun with windows closed and it cooled down to 38.5F center vent temp in 2 miles of city driving. Not bad at all! In a long highway cruise, I think the vent temp can get even lower.

Problem before was a slow leak that requires yearly topping up of refrigerant. I won't know if my work is successful for a few months or more.

__________________
85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked