O-Rings

CAUTION: Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose, and throat. To remove R-134a from the A/C system, use service equipment certified to meet the requirements of SAE J 2210 or SAE J 2209. If accidental system discharge occurs, ventilate work area before resuming service. Additional health and safety information may be obtained from refrigerant and lubricant manufacturers. Do not store or heat refrigerant containers above 52°C (125°F). Do not heat a refrigerant container with an open flame; if container warming is required, place the bottom of the container in a pail of warm water. Do not intentionally drop, puncture, or incinerate refrigerant containers. Refrigerant will displace oxygen, therefore be certain to work in well ventilated areas to prevent suffocation. If it is necessary to carry a container of Dot CFR Refrigerant-134a in a vehicle, it should not be carried in the passenger compartment. Only containers that meet DOT SPEC 4BA or 4BW should be used.

NOTICE: R-12 refrigerant and R-134a refrigerant must never be mixed, even in the smallest of amounts, as they are incompatible with each other. If the refrigerants are mixed, compressor failure is likely to occur. Use only polyalkylene glycol (PAG) synthetic refrigerant oil for internal circulation through the R-134a A/C system and only mineral base 525 viscosity refrigerant oil on fitting threads and O-rings. If lubricants other than those specified are used, compressor failure and/or fitting seizure is likely to occur. Do not introduce compressed air to any refrigerant container or refrigerant component, because contamination will occur.


Install new GM-approved service replacement air conditioning O-rings when a joint or a fitting is installed, except when the O-rings are provided on new replacement components. Unless service replacement O-rings of the specified part numbers are used, excessive leakage of Refrigerant-134a may occur. Refer to the part number for identification, not to the former color-coating method of identification, because some formerly color-coated service replacement O-rings may be black.

Air conditioning O-rings should be coated with mineral base 525 viscosity refrigerant oil just before installation and should be slipped onto the flange tube to assure proper locating and sealing. To prevent the possibility of swelling and a reduction in sealing effectiveness, O-rings should not be allowed to soak in refrigerant oil. Before installation, the O-rings and the fittings should be examined to insure that they have not been nicked or deformed. Nicked or deformed parts must be replaced or excessive refrigerant leakage may result.