GM Service Manual Online
For 1990-2009 cars only

Evaporator Tube Replacement Front

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Remove the upper radiator support. Refer to Radiator Support Replacement in Engine Cooling.

  3. Object Number: 380079  Size: SH
  4. Remove the refrigerant pressure sensor. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement .

  5. Object Number: 297294  Size: SH
  6. Remove the front evaporator tube to condenser retaining bolt.
  7. Important: Cap or tape the open front evaporator tube and the condenser immediately to prevent contamination.

  8. Disconnect the front evaporator tube from the condenser, discard the O-ring .

  9. Object Number: 297295  Size: SH
  10. Remove the front evaporator tube to rear evaporator tube retaining bolt.
  11. Important: Cap or tape the open evaporator tubes immediately to prevent contamination.

  12. Disconnect the front evaporator tube from the rear evaporator tube, discard the O-ring.

Installation Procedure

  1. Remove the cap or tape from the evaporator tubes.
  2. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the front evaporator tube and the rear evaporator tube.

  3. Object Number: 297232  Size: SH
  4. Lightly coat the new O-ring seal (1) with mineral base 525 viscosity refrigerant oil.
  5. Important: DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the O-ring seal to enter the refrigerant system.


    Object Number: 297228  Size: SH
  6. Carefully slide the new O-ring (1) onto the front evaporator tube until seated.
  7. Leave a light coating of the refrigerant oil to remain on the front evaporator tube in the area indicated (2) ONLY.


    Object Number: 297295  Size: SH
  8. Install the front evaporator tube to the rear evaporator tube.
  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 front evaporator tube to rear evaporator tube retaining bolt.
  11. Tighten
    Tighten the evaporator tube retaining bolt to 25 N·m (18 lb ft).

  12. Remove the cap or tape from the front evaporator tube and the condenser.
  13. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the front evaporator tube and the condenser.

  14. Object Number: 297228  Size: SH
  15. Lightly coat the new O-ring seal (1) with mineral base 525 viscosity refrigerant oil.
  16. Important: DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the O-ring to enter the refrigerant system.

  17. Carefully slide the new O-ring (1) onto the front evaporator tube until seated.
  18. Leave a light coating of the refrigerant oil to remain on the evaporator tube in the area indicated (2) ONLY.


    Object Number: 297294  Size: SH
  19. Install the front evaporator tube to the condenser.
  20. Install the front evaporator tube to condenser retaining bolt.
  21. Tighten
    Tighten the evaporator tube to condenser retaining bolt to 27 N·m (20 lb ft).


    Object Number: 380079  Size: SH
  22. Install the refrigerant pressure sensor. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement .
  23. Install the upper radiator support. Refer to Radiator Support Replacement in Engine Cooling.
  24. Evacuate and charge the refrigerant system. Refer to Refrigerant Recovery and Recharging .
  25. Check the condenser and evaporator tube joints for leaks. Refer to Leak Testing .

Evaporator Tube Replacement Rear

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Remove the battery. Refer to Battery Replacement in Engine Electrical.

  3. Object Number: 284760  Size: SH
  4. Remove the battery heat shield. Refer to Battery Heat Shield Replacement in Body Front End.
  5. Remove the engine intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.

  6. Object Number: 621749  Size: SH
  7. Remove the nut retaining the heater pipe bracket to the dash panel.
  8. Reposition the heater pipe bracket to access the refrigerant lines.

  9. Object Number: 621746  Size: SH
  10. Remove the front evaporator tube to rear evaporator tube retaining bolt.
  11. Important: Cap or tape the open evaporator tubes immediately.

  12. Disconnect the evaporator tubes, discard the O-ring.

  13. Object Number: 621748  Size: SH
  14. Loosen the accumulator hose to evaporator retaining bolt.
  15. Important: Cap or tape the open rear evaporator tube and the evaporator immediately to prevent contamination.

  16. Disconnect the rear evaporator tube from the accumulator hose bracket at the evaporator, discard the O-ring.

Installation Procedure

  1. Remove the cap or tape from the rear evaporator tube and evaporator.
  2. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the rear evaporator tube and evaporator.

  3. Object Number: 297232  Size: SH
  4. Lightly coat the new O-ring (1) with mineral base 525  viscosity refrigerant oil.
  5. Important: DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the O-ring to enter the refrigerant system.


    Object Number: 297228  Size: SH
  6. Carefully slide the new O-rings (1) onto the rear evaporator tube and evaporator until seated.

  7. Object Number: 621747  Size: SH
  8. Position the rear evaporator tube with the accumulator hose bracket and install the assembly to the evaporator.

  9. Object Number: 621748  Size: SH
  10. Tighten the accumulator hose to evaporator retaining bolt.
  11. Tighten
    Tighten the accumulator hose to evaporator retaining bolt to 16 N·m (12 lb ft).

  12. Remove the cap or tape from the front evaporator tube.
  13. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the front evaporator tube where it connects to the rear evaporator tube.

  14. Object Number: 297232  Size: SH
  15. Lightly coat the O-ring (1) with mineral base 525  viscosity refrigerant oil.
  16. Important: DO NOT allow any of the mineral base 525  viscosity refrigerant oil on the O-ring to enter the refrigerant system.


    Object Number: 297228  Size: SH
  17. Carefully slide the new O-ring (1) onto the front evaporator tube until seated.
  18. Leave a light coating of the refrigerant oil to remain on the front evaporator tube in the area indicated (2) ONLY.


    Object Number: 621746  Size: SH
  19. Install the front evaporator tube to the rear evaporator tube with retaining bolt.
  20. Tighten
    Tighten the front evaporator tube to the rear evaporator tube retaining bolt to 25 N·m (18 lb ft).


    Object Number: 621749  Size: SH
  21. Install the heater pipe bracket to the dash panel stud.
  22. Install the heater pipe bracket retaining nut.
  23. Tighten
    Tighten the heater pipe bracket retaining nut to 10 N·m (89 lb in).


    Object Number: 65170  Size: SH
  24. Install the engine intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.

  25. Object Number: 284760  Size: SH
  26. Install the battery heat shield. Refer to Battery Heat Shield Replacement in Body Front End.

  27. Object Number: 74060  Size: SH
  28. Install the battery. Refer to Battery Replacement in Engine Electrical.
  29. Program the transmitters. Refer to Transmitter Programming/Synchronization in Keyless Entry.
  30. Evacuate and charge the refrigerant system. Refer to Refrigerant Recovery and Recharging .
  31. Check the evaporator and evaporator tube joints for leaks. Refer to Leak Testing .