Flushing (Front Only System)

Tools Required

• J 43600  ACR 2000 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 42220  Universal 12V Leak Detection Lamp. See Special Tools and Equipment .

Flushing is intended to remove the following contaminants:

• 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. Refer to Refrigerant Recovery and Recharging .
2. Remove the orifice tube. Refer to Expansion (Orifice) Tube Replacement (Front Only System)  or Expansion (Orifice) Tube Replacement (Auxiliary System) .
3. Connect the A/C lines with the orifice tube removed.
4. Remove the A/C compressor. Refer to Compressor Replacement (LL8)  or Compressor Replacement (LM4) .
5. Install J 45268-2 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 ACDelco P/N GF 470, before each flush.

      Connect J 45268-1 flush filter to the suction port of J 45268-4 flush adapter.

   2. Connect the blue hose from J 43600  to J 45268-1 flush filter adapter. See Special Tools and Equipment .
   3. Connect the red hose from J 43600  to J 45268-5. See Special Tools and Equipment .
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 ACDelco P/N GF 470, before each flush.
   2. Connect J 45268-1 flush filter to the discharge port of J 45268-5 flush adapter.
   3. Connect the blue hose from J 43600  to J 45268-1 flush filter adapter. See Special Tools and Equipment .
   4. Connect the red hose from J 43600  to the suction port of J 45268-4. See Special Tools and Equipment .
IMPORTANT: Close the valve on the external refrigerant tank, before starting the flush process.
8. Flush the front A/C system. Follow the instructions supplied with the J 43600  . See Special Tools and Equipment .
9. Remove J 45268-4 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:
    1. Remove the A/C compressor drain plug.
    2. 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.
    3. Install the A/C compressor drain plug.

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

    4. 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:
    1. Determine if the new service compressor is shipped with PAG oil. Refer to the Refrigerant System Capacities .
    2. The service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor.
    3. 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 .
    4. Add the calculated amount to the compressor, as needed.
IMPORTANT: Flushing will remove the fluorescent leak detection dye from the A/C system.
12. Add one bottle of J 41447  directly to the A/C compressor. See Special Tools and Equipment .
13. Install the A/C compressor. Refer to Compressor Replacement (LL8)  or Compressor Replacement (LM4) .
14. Inspect the orifice tube for debris. Clean or replace as needed.
15. Install the orifice tube. Refer to Expansion (Orifice) Tube Replacement (Front Only System)  or Expansion (Orifice) Tube Replacement (Auxiliary System) .
16. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
17. Leak test the fittings using J 42220  . See Special Tools and Equipment .