GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 39400-A Halogen Leak Detector
    • J 26549-E Orifice Tube Remover

Removal Procedure

Important: When you replace an expansion (orifice) tube, compare the design of the orifice tube to the design of the replacement part for the correct selection. The different styles of orifice tubes are not interchangeable.


    Object Number: 588303  Size: SH
  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the bolt holding the evaporator hose assembly to the condenser.
  4. Remove the evaporator hose assembly from the condenser.
  5. Important: Immediately cap or tape the open end of the condenser line to prevent contamination.

  6. Remove and discard the seal washer.
  7. Use J 26549-E to remove the orifice tube.
  8. Use the following procedure in order to remove a restricted or plugged expansion (orifice) tube:
  9. 7.1. Remove as much as possible of the impacted residue.
    7.2. Use a heat gun in order to apply heat to the expansion (orifice) tube. Apply the heat approximately 7 mm (1/4 in) from the dimples on the inlet pipe.
    7.3. While applying heat, use pliers in order to grip the orifice tube. Use a turning motion along with a push-pull motion.

    This will loosen the impacted orifice tube and remove the tube.

    7.4. Swab the inside of the evaporator inlet line to clean any contamination from the line.

    Object Number: 296238  Size: SH
  10. Inspect the expansion orifice tube for the following conditions and clean or replace with a new tube as indicated:
  11. • Broken plastic frame; replace tube
    • Filter screen (1,2) torn, damaged or plugged with fine gritty material; replace tube
    • Brass orifice tube (3) damaged or plugged; replace tube
    • Filter screen (1) coated with metal chips, flakes, or slivers; coating may be removed with low pressure shop air and reused if cleaned satisfactorily
    • If reusing the orifice tube, install a new O-ring (4)

Installation Procedure


    Object Number: 296238  Size: SH
  1. Lightly coat the new orifice tube O-ring seal (4) with mineral base 525 viscosity refrigerant oil.
  2. Remove the cap or tape from the evaporator line.
  3. Using J 26549-E , CAREFULLY grasp the edge of the expansion orifice tube (long filter screen (1) inlet side of tube).
  4. Insert the orifice tube into the evaporator line, beginning with the short filter screen (2) outlet side.
  5. Remove the cap or tape from the condenser line.
  6. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the line fittings.

  7. Object Number: 588303  Size: SH
  8. Install a new seal washer on the condenser tube. Refer to Sealing Washer Replacement on page 1-45.
  9. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Install the evaporator hose assembly to the condenser.
  11. Install the evaporator hose assembly bolt to the condenser.

    Tighten
    Tighten the bolt to 25 N·m (18 lb ft).

  12. Lower the vehicle.
  13. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging .
  14. Leak test the fittings of the component using the J 39400-A .