1993 Jeep Cherokee A/C Compressor Refrigerant Oil Checking

For compressor application, see COMPRESSOR APPLICATIONS & BODY DESIGNATIONS in this article. DO NOT exceed A/C system refrigerant oil capacity when servicing system. See REFRIGERANT OIL & REFRIGERANT SPECIFICATIONS in this article.
REFRIGERANT OIL & REFRIGERANT
Due to late changes, always refer to underhood A/C Specification Label in engine compartment or A/C compressor label while servicing A/C system. If A/C Specification Label and specifications in table differ, use label specifications.
REFRIGERANT OILS
Only NEW, pure, moisture-free refrigerant oil should be used in A/C systems. This oil is highly refined with a very low moisture content. Oil container must be tightly closed when not in use, or moisture from air will be absorbed into refrigerant oil. Refrigerant R-12 based systems use mineral oil, while R-134a systems use synthetic/Polyalkylene Glycol (PAG) oil. Using a mineral oil based lubricant with R-134a systems will result in A/C compressor failure due to lack of proper lubrication.
Use ONLY specified oil for the appropriate system and A/C compressor. Always check the underhood A/C specification label or A/C compressor label before adding refrigerant oil to A/C compressor/system. The following types of R-134a refrigerant oil are currently available.
NOTE: Chrysler/Jeep/Eagle PAG (ND8) Refrigerant Oil (82300102) Synthetic/PAG oil absorbs moisture very rapidly, 2.3-5.6 percent by weight as compared to a mineral oil absorption rate of .005 percent by weight.
SERVICING PRECAUTIONS DISCHARGING SYSTEM
If compressor has stem-type service valves, it can be isolated and removed without discharging entire system. Otherwise, discharge A/C system using approved refrigerant recovery/recycling equipment before loosening any fittings.
DISCONNECTING LINES & FITTINGS
After system is discharged, carefully clean area around all fittings to be opened. Always use 2 wrenches when loosening or tightening fittings. Some refrigerant lines are connected with a coupling. Special tools may be required to disconnect lines. Cap all openings as soon as lines are removed. DO NOT remove caps until ready to connect lines and fittings.
NOTE: All R-134a based systems use 1/2-16 ACME threaded fittings. Ensure all replacement parts match the connections of the system being worked on.

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