Repair Instructions: Flushing

Tools Required: 

• J 43600  ACR 2000 Refrigerant Station
• J 45268  Flush Adapter Kit
• J 41447  Leak Detection Dye
• J 41459  Leak Detection Dye Injector
• J 42220  Universal 12V Leak Detection Lamp

Important:  Flushing 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 & 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 (L35 W/Harrison) , Compressor Replacement (LB7 w/Denso) , Compressor Replacement (LB7 w/Harrison) , Compressor Replacement (LR4, LM7, LQ4, L18 w/Denso)  or Compressor Replacement (L18 w/Harrison)  .
5. Install the J 45268-3 to the A/C compressor hose assembly.
6. 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. 6.1. 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. 6.2. Connect the blue hose from the J 43600  to the J 45268-1 flush filter adapter.
   3. 6.3. Connect the red hose from the J 43600  to the J 45268-3.
Fig 1: Flush Adapter Kit Filter
Courtesy of GENERAL MOTORS CORP.
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 the J 45268-1 is serviceable. Remove and discard the check valve from the filter.

   1. 7.1. 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. 7.2. Connect the blue hose from the J 43600  to the J 45268-1 flush filter adapter.
   3. 7.3. Connect the red hose from the J 43600  to the suction port of the J 45268-3.
8. Flush the A/C system. Follow the instructions supplied with the J 43600. 

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

9. Remove the J 45268-3 from the A/C compressor hose assembly.
   • 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.

   • Install the A/C compressor drain plug. Tighten the drain plug to 20 N.m (15 lb ft).
10. Install the A/C compressor. Refer to Compressor Replacement (L35 W/Harrison) , Compressor Replacement (LB7 w/Denso) , Compressor Replacement (LB7 w/Harrison) , Compressor Replacement (LR4, LM7, LQ4, L18 w/Denso)  or Compressor Replacement (L18 w/Harrison)  .
11. Inspect the orifice tube for debris.

    Clean or replace as needed.

12. Install the orifice tube. Refer to Expansion (Orifice) Tube Replacement .
13. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery & Recharging .

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

14. 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.

15. Add one bottle of J 41447  using the J 41459. 
16. Leak test the fittings using the J 42220.