Repair Instructions: Flushing

Tools Required

• J 41447  Leak Detection Dye
• J 42220  Universal 12V Leak Detection Lamp
• J 43600  Air Conditioning Service Center
• J 45268  Flush Adapter Kit

Flushing is intended to remove the following:

• Contaminated polyalkylene glycol (PAG) oil
• Desiccant, following a desiccant bag failure
• Overcharge of PAG oil
• Refrigerant contamination

IMPORTANT:

Warmer engine or ambient temperature decreases the refrigerant recovery time during the A/C flush procedure.

1. Recover the refrigerant. Refrigerant Recovery and Recharging .
2. Remove the orifice tube. Expansion (Orifice) Tube Replacement .
3. Connect the A/C lines with the orifice tube removed.
4. Remove the A/C compressor. Air Conditioning Compressor Replacement (LWN) Air Conditioning Compressor Replacement (LV1) Air Conditioning Compressor Replacement (L96, LC8) .
5. Inspect the end of the suction hose for a suction screen.
6. Remove the suction screen, if installed.
7. Install the J 45268-3 to the A/C compressor hose assembly.

8. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil.

   Perform the following procedure:

   IMPORTANT:

   The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter.

   1. Service the filter with ACDelco P/N GF 470, before each flush.

      Connect the J 45268-1 flush filter to the suction port of the J 45268-3 flush adapter.

   2. Connect the blue hose from the J 43600  center to the J 45268-1 flush filter adapter.
   3. Connect the red hose from the J 43600  center to the J 45268-3 flush adapter.
9. Reverse flow refrigerant flushing is recommended for desiccant bag failure.

   Perform the following procedure and replace the accumulator when the flush procedure is complete.

   IMPORTANT:

   The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter.

   1. Service the filter with ACDelco P/N GF 470, before each flush.

      Connect the J 45268-1 flush filter to the discharge port of the J 45268-3 flush adapter.

   2. Connect the blue hose from the J 43600  center to the J 45268-1 flush filter adapter.
   3. Connect the red hose from the J 43600  center to the suction port of the J 45268-3 flush adapter.
10. Flush the front A/C system. Follow the instructions supplied with the J 43600  center.

    Close the valve on the external refrigerant tank, before starting the flush process.

IMPORTANT:

Flush the front A/C system before flushing the auxiliary A/C system.

11. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.

12. Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube.

13. IMPORTANT:

    Pinch off the orifice tube in order to prevent refrigerant flow to the front system during the auxiliary system flush.

    Install the pinched orifice tube. Expansion (Orifice) Tube Replacement .

14. Remove the auxiliary thermostatic expansion valve (TXV). Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement .
15. Install the J 45268-104.
IMPORTANT:

The auxiliary evaporator core can be flushed without totally reassembling into the auxiliary HVAC module.

16. Install the auxiliary evaporator core to the A/C lines.
17. Raise the vehicle. Lifting and Jacking the Vehicle .
18. Connect the auxiliary A/C lines to the auxiliary evaporator core.
19. Lower the vehicle.
20. Flush the auxiliary A/C system. Follow the instructions supplied with the J 43600  center.
21. Raise the vehicle. Lifting and Jacking the Vehicle .
22. Remove the auxiliary A/C lines from the auxiliary evaporator core.
23. Lower the vehicle.
24. Remove the J 45268-104.
25. Inspect the TXV for debris.

    Clean or replace, as needed.

26. Install the auxiliary TXV. Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement .
27. Remove the J 45268-3 from the A/C compressor hose assembly.
IMPORTANT:

Flushing will remove all the PAG oil from the A/C system. The A/C system must be replenished with the correct amount of PAG oil.

28. Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor.
29. Add back the total system capacity of PAG oil to the A/C compressor. Approximate Fluid Capacities .
30. If you will be replacing the A/C compressor after flushing the system, perform the following procedure:
    • Determine if the new service compressor is shipped with PAG oil. Approximate Fluid Capacities .
    • If the service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor.
    • Deduct the amount of PAG oil shipped with the service compressor from the amount of PAG oil listed in the capacities table. Approximate Fluid Capacities .
    • Add the calculated amount to the compressor, as needed.
IMPORTANT:

Flushing will remove the fluorescent leak detection dye from the A/C system.

31. Add one bottle of J 41447  dye.
32. Install the A/C compressor. Air Conditioning Compressor Replacement (LWN) Air Conditioning Compressor Replacement (LV1) Air Conditioning Compressor Replacement (L96, LC8) .
33. Install a new orifice tube. Expansion (Orifice) Tube Replacement .
34. Evacuate and recharge the A/C system. Approximate Fluid Capacities .
35. Leak test the fittings using the J 42220  lamp.