GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2000 🢒 Century 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Expansion (Orifice) Tube Replacement

Removal Procedure
  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Remove the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in 3.1L Engine Controls or Air Cleaner Assembly Replacement in 3.8L Engine Controls.
  3. Remove the cross vehicle brace if equipped. Refer to Cross Vehicle Brace Replacement in Body Front End.
  4. Remove the vacuum brake booster. Refer to Power Vacuum Brake Booster Replacement in Hydraulic Brakes.
  5. Remove the condenser tube. Refer to Condenser Tube Replacement .
  6. Remove the expansion (orifice) tube:
    7. 6.1. Use needle-nose pliers in order to grip the orifice tube.
    6.2. Use a turning motion along with a push-pull motion in order to loosen the impacted orifice tube.
    6.3. Remove the orifice tube.

    Object Number: 493641 Size: SH

    Important: DO NOT use any solvents or chemicals to clean the expansion (orifice) tube porous plastic inlet filter.

  7. Inspect the expansion (orifice) tube for the following conditions and clean or replace with a new tube as indicated:
    8. • Broken plastic frame (1) ; replace tube.
    • Inlet filter (3) damaged or plugged with fine gritty material; replace tube.
    • Inlet filter (3) coated with metal chips, flakes, or slivers; coating may be removed with low pressure shop air ONLY and reused if cleaned satisfactorily.
    • If reusing the tube, discard the O-ring seals (2).

Installation Procedure

    Object Number: 493641 Size: SH

    Important: Lubricate the new O-ring seals (2) with mineral base 525 viscosity refrigerant oil.

  1. Install the new O-ring seals (2), if reusing the orifice tube.
  2. CAREFULLY grasp the edge of the expansion (orifice) tube (1) without touching the inlet filter (porous plastic) (3) and insert into the condenser tube until fully seated.
  3. Install the condenser tube. Refer to Condenser Tube Replacement .
  4. Install the cross vehicle brace if equipped. Refer to Cross Vehicle Brace Replacement in Body Front End.
  5. Install the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in 3.1L Engine Controls or Air Cleaner Assembly Replacement in 3.8L Engine Controls.
  6. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging .
  7. Leak test the filling(s) of the repaired or the reinstalled component using J 39400 .