Operation CHARM: Car repair manuals for everyone.

O-Rings

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.