Compressor Oil Check: Notes
Oil level on Air-Temp, Tecumseh, and York compressors may be checked with compressor mounted in vehicle. If these compressors are equipped with stem-type service valves, compressor may be "isolated", thereby avoiding necessity of discharging entire system (see COMPRESSOR ISOLATING or related paragraphs). General Motors (6 Cylinder) compressors may have to be removed from vehicle for oil check, as filler plug is located near the bottom of the compressor (refer to appropriate method for procedures). After oil level is checked and adjusted, A/C system must be evacuated and recharged before it can be put back into service.