How do you charge ac on a 1980 Oldsmobile cutlass supreme?

To charge the AC on a 1980 Oldsmobile Cutlass Supreme, first ensure the engine is running and the AC is set to the maximum cool setting. Locate the low-pressure service port, typically found on the larger AC line, and connect the refrigerant canister with the correct R-12 refrigerant or an appropriate substitute if retrofitted. Open the valve on the canister and monitor the pressure gauge to avoid overcharging. Once the system reaches the desired pressure, disconnect the canister and check for cooling efficiency.