GM-GMC: A/C Compressor Oil, compressor oil, condenser

Question
I have and 84 GM with a Harrison (the round black one, not aluminum) A/C compressor and I need to know how much compressor oil it holds.

Answer
It depends on what maintenance you are performing and what compressor you have.  A-6 is the long compressor and R-4 is the short round compressor.

From the 1984 shop manual:

System total capacity:  A-6 is 10 ounces  R-4 is 6 ounces.

To prevent overcharging with oil, if just the compressor is being serviced, measure amount of old oil and replace with same amount plus 1 ounce.  If more than 8 ounces drains out of an A-6, suspect overcharge of oil.

Evaporator change - add 3 ounces.

Condenser change - add 1 ounce.

Accumulator (filter/dryer) change - measure amount of old oil and replace with same amount plus 2 ounces of oil.