Repair Instructions: Flushing

Tools Required

• J 43600  Air 2000 Air Conditioning Service Center. See Special Tools .
• J 45268  A/C Flushing Adapter Kit. See Special Tools .
• J 41447  R-134A A/C Tracer Dye - Box of 24. See Special Tools .
• J 42220  Universal 12V Leak Detection Lamp. See Special Tools .

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 (3.4L)  or Compressor Replacement (3.8L) .
5. Install the J 45268-3 to the A/C compressor hose assembly.
Fig 1: View Of A/C Filter And Check Valve
Courtesy of GENERAL MOTORS CORP.
6. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil.

   Perform the following procedure:

   IMPORTANT: The filter inside J 45268-1 is serviceable. Remove and discard the check valve from the filter.
   1. Service the filter with AC Delco 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  to the J 45268-1 flush filter adapter. See Special Tools .
   3. Connect the red hose from the J 43600  to the J 45268-3. See Special Tools .
7. Reverse flow refrigerant flushing is recommended for desiccant bag failure only. Perform the following procedure and replace the accumulator when the flush is complete:
   IMPORTANT: The filter inside J 45268-1 is serviceable. Remove and discard the check valve from the filter.
   1. Service the filter with AC Delco P/N GF 470, before each flush.
   2. Connect the J 45268-1 flush filter to the discharge port of the J 45268-3 flush adapter.
   3. Connect the blue hose from the J 43600  to the J 45268-1 flush filter adapter. See Special Tools .
   4. Connect the red hose from the J 43600  to the suction port of the J 45268-3. See Special Tools .
IMPORTANT: Close the valve on the external refrigerant tank, before starting the flush process.
8. Flush the A/C system. Follow the instructions supplied with the J 43600  . See Special Tools .
9. 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.
10. If you will reinstall the removed A/C compressor, perform the following procedure:
    • Remove the A/C compressor drain plug.
    • Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor.
    NOTE: Refer to Fastener Notice in Cautions and Notices.
    • Install the A/C compressor drain plug.

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

    IMPORTANT: Flushing will remove the fluorescent leak detection dye from the A/C system.
    • Add one bottle of J 41447  . See Special Tools .
    • Add the total system capacity of PAG oil to the A/C compressor. Refer to Refrigerant System Capacities  .
11. If you will replace the A/C compressor after flushing the system, perform the following procedure:
    • Determine if the new service compressor is shipped with PAG oil. Refer to the 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  .
    IMPORTANT: Flushing will remove the fluorescent leak detection dye from the A/C system.
    • Add one bottle of J 41447  . See Special Tools .
12. Install the A/C compressor. Refer to Compressor Replacement (3.4L)  or Compressor Replacement (3.8L) .
13. Inspect the orifice tube for debris. Clean or replace as needed. Refer to Expansion (Orifice) Tube Replacement .
14. Install the orifice tube. Refer to Expansion (Orifice) Tube Replacement .
15. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
16. Leak test the fittings using the J 42220  . See Special Tools .