Flushing Procedure

Tools Required 

• J 43600  Air Conditioning Service Center. See Special Tools and Equipment .
• J 45268  Flush Adapter Kit. See Special Tools and Equipment .
• J 41447  Leak Detection Dye. See Special Tools and Equipment .
• J 41459  Leak Detection Dye Injector. See Special Tools and Equipment .
• J 42220  Universal 12V Leak Detection Lamp. See Special Tools and Equipment .

Important:  Flushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following:

• Contaminated 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. Refer to REFRIGERANT RECOVERY AND RECHARGING .
2. Remove the orifice tube. Refer to EXPANSION (ORIFICE) TUBE REPLACEMENT .
3. Connect the A/C lines with the orifice tube removed.
4. Remove the A/C compressor. Refer to COMPRESSOR REPLACEMENT .
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. 8.1. 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. 8.2. Connect the blue hose from the J 43600  to the J 45268-1 flush filter adapter.
   3. 8.3. Connect the red hose from the J 43600  to the J 45268-3 flush adapter.
   Fig 1: Removing Check Valve From Filter

   Courtesy of GENERAL MOTORS CORP.
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. 9.1. 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. 9.2. Connect the blue hose from the J 43600  to the J 45268-1 flush filter adapter.
   3. 9.3. Connect the red hose from the J 43600  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. 

    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.
    Fig 2: Cutting Orifice Tube

    Courtesy of GENERAL MOTORS CORP.

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

    Fig 3: Identifying Orifice Tube

    Courtesy of GENERAL MOTORS CORP.
13. Install the pinched orifice tube. Refer to EXPANSION (ORIFICE) TUBE REPLACEMENT .
14. Remove the auxiliary TXV. Refer to THERMAL EXPANSION VALVE REPLACEMENT - AUXILIARY .
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. Refer to LIFTING AND JACKING THE VEHICLE in General Information.
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. 
21. Raise the vehicle. Refer to LIFTING AND JACKING THE VEHICLE in General Information.
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. Refer to THERMAL EXPANSION VALVE REPLACEMENT - AUXILIARY .
27. Remove the J 45268-3 from the A/C compressor hose assembly.
    NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
28. If the suction hose had a suction screen before flushing, replace the screen. Refer to SUCTION SCREEN REPLACEMENT .
    • Remove the A/C compressor drain plug.
    • Rotate the compressor input shaft to assist in draining the PAG oil from the A/C compressor.
    • Install the A/C compressor drain plug.

      Tighten 

      Tighten the drain plug to 20 N.m (15 lb ft).

29. If replacing the A/C compressor after flushing the system, perform the following:
    • Determine if the new service compressor is shipped with PAG oil. Refer to REFRIGERANT SYSTEM 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. Refer to REFRIGERANT SYSTEM CAPACITIES . Add the calculated amount to the compressor, as needed.
    • If the service compressor is shipped dry, no calculation is required. Add the total system capacity of PAG oil to the compressor. Refer to REFRIGERANT SYSTEM CAPACITIES .
30. Install the A/C compressor. Refer to COMPRESSOR REPLACEMENT .
31. Install a new orifice tube. Refer to EXPANSION (ORIFICE) TUBE REPLACEMENT .
32. Evacuate and recharge the A/C system. Refer to REFRIGERANT RECOVERY AND RECHARGING .

    Important:  Flushing will remove all of the PAG oil from the A/C system.

33. Add the total system capacity of PAG oil to the A/C system. Refer to REFRIGERANT SYSTEM CAPACITIES .

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

34. Add one bottle of J 41447  using the J 41459. 
35. Leak test the fittings using the J 42220.