O-Rings

Dual O-Rings:

Tool Required:
J 38042 Dual O-Ring Tube Separator

Install new GM-approved service replacement air conditioning O-rings whenever a joint or fitting is disassembled, except when provided on new components. Even though O-rings may look the same, it is extremely important that only recommended service replacement air conditioning O-rings be used, otherwise excessive leakage of Refrigerant-134a may occur.

When replacing O-rings on an air conditioning component or joint connection, the fitting design should be carefully identified to ensure installation of the correct air conditioning service replacement O-ring.

This vehicle uses dual O-ring joints in the system. This design increases the durability of the joint seal by providing a second O-ring seal. The dual O-ring fitting consists of:

^ An aluminum-alloy, externally threaded fitting which is brazed or welded to an aluminum tube.
^ A free-spinning, plated steel internally threaded nut.
^ A precision machined, male-piloted aluminum tube end which accommodates two O-rings.

When servicing dual O-ring joints, the following procedures should be followed:

^ Completely recover refrigerant from the system.
^ Use a J 38042 dual O-ring tube separator to separate the joint while loosening the female nut.
^ Whenever a fitting joint is opened, replace the O-rings with new ones.
^ Use a nonmetallic tool when removing O-rings to prevent the chance of damaging the seal surface.
^ Avoid excessive stretching and twisting of replacement O-rings.
^ Align the end forms for pilot-to-bore insertion, then push together completely.
^ Application of a small amount of 525 viscosity A/C oil will ease insertion.

NOTICE: The use of proper wrenches when loosening or making connections is important. A backup wrench should be used on the brazed or welded fitting to prevent distortion of the A/C lines.

Important
^ Dual O-ring fittings are different in size from standard A/C fitting O-rings.
^ Dual O-ring fittings require that the steel nut be tightened to a torque of 24 N.m (18 lb. ft.)


Prior to installation, verify that both O-rings and fittings have not been nicked or deformed. Deformed or nicked parts must be replaced. Failure to use the proper service replacement parts and procedures may result in excessive Refrigerant-134a leakage.