Flushing with Auxiliary A/C

Special Tools

Note: Vehicles with auxiliary A/C must flush both the front and auxiliary A/C System to adequately flush the entire A/C System.

Flushing is intended to remove the following:

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

Note: Inspect and lubricate the J 45268 fitting O-rings. Refer to O-Ring Replacement.

1. Install the J 45268-7 (2) onto the suction line adapter block J 45268-13 (1).
2. Install the J 45268-8 (3) onto the discharge line adapter block J 45268-12 (4).

Note: Reverse flow refrigerant flush is recommended for desiccant bag failure. Replace the condenser/receiver dehydrator assembly when the A/C flush is complete and perform the following procedure:

Note: Inspect and lubricate the J 45268 fitting O-rings. Refer to O-Ring Replacement.

1. Install the J 45268-8 (2) onto the suction line adapter block J 45268-13 (1).
2. Install the J 45268-7 (3) onto the discharge line adapter block J 45268-12 (4).

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

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging.



2. Remove the front thermal expansion valve (TXV). Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.
3. Inspect the O-rings on the evaporator core and A/C lines and replace as necessary. Refer to O-Ring Replacement.
4. Install the A/C lines into J 45268-110.
5. Install J 45268-110 onto the evaporator core.
6. Install the TXV line bracket.

Caution: Refer to Fastener Caution in the Preface section.




7. Install TXV mounting bolts and tighten to 3.5 N·m (31 lb in).
8. Remove the A/C compressor. Refer to Air Conditioning Compressor Replacement.




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

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

Note: Arrange the J 45268-7 flush fitting and J 45268-8 flush fitting in the forward flushing setup.

10. Inspect the O-rings on the A/C discharge and suction lines and replace as necessary. Refer to O-Ring Replacement
11. Install the J 45268-13 to the A/C suction line.
12. Install the J 45268-12 to the A/C discharge line.



13. Connect the J 45268-1 flush filter to the J 45268-7 flush fitting.
14. Connect the blue hose from the J 43600 to J 45268-1 flush filter adapter.
15. Connect the red hose from the J 43600 to J 45268-8 flush fitting.

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

16. Flush the A/C system. Follow the instructions supplied with the J 43600 .
17. Remove the front TXV mounting bolts.



18. Remove the front TXV line bracket.
19. Remove J 45268-110 from the evaporator core.



20. Remove the A/C lines from J 45268-110.
21. Inspect the TXV for debris. Clean or replace as needed.

Note: Do not install the instrument panel (I/P) until after the forward flushing of the auxiliary system procedure is completed.

22. Install the TXV. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.

1. Remove the auxiliary TXV. Refer to Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement.
2. Install the J 45268-111 in place of the auxiliary TXV.
3. Install auxiliary TXV assembly onto the evaporator core.
4. Install auxiliary TXV mounting bolts and tighten to 3.5 N·m (31 lb in).




Note: It is not necessary to reinstall the auxiliary evaporator core into the auxiliary HVAC module prior to flushing.

5. Connect the auxiliary evaporator core inlet line to the auxiliary evaporator core and tighten the nut to 9 N·m (80 lb in).



6. Connect the auxiliary evaporator core outlet line to the auxiliary evaporator core and tighten the nut to 9 N·m (80 lb in).




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

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




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

8. Flush the auxiliary A/C System. Follow the instructions supplied with the J 43600 .
9. Disconnect the red hose from the J 43600 to J 45268-8 flush fitting.
10. Disconnect the blue hose from the J 43600 to J 45268-1 flush filter adapter.
11. Disconnect the J 45268-1 flush filter from the J 45268-7 flush fitting.
12. Remove the J 45268-12 from the A/C discharge line.
13. Remove the J 45268-13 from the A/C suction line.




Note: 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.
14. If you will reinstall the removed A/C compressor, perform the following procedure:

14.1.

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: Rotating the compressor hub assembly when adding PAG oil to the A/C compressor suction port will draw the PAG oil into the crankcase chamber and prevent overflow.

14.2.

Add the total system capacity of PAG oil into the suction port of the A/C compressor while slowly rotating the A/C compressor hub assembly. Refer to Refrigerant System Capacities.

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

14.3.

Add one bottle of J 41447 fluorescent dye directly into the A/C compressor suction port while slowly rotating the A/C compressor hub assembly.

Note: A new service compressor is shipped with a full charge of PAG oil. Refer to Refrigerant System Capacities.

15. Install the A/C compressor. Refer to Air Conditioning Compressor Replacement.
16. Remove the auxiliary evaporator core outlet line to auxiliary evaporator core nut.



17. Disconnect the auxiliary evaporator core outlet line from the auxiliary evaporator core.
18. Remove the auxiliary evaporator core inlet line to auxiliary evaporator core nut.



19. Disconnect the auxiliary evaporator core inlet line to the auxiliary evaporator core.

Tighten the nut to 9 N·m (80 lb in).

20. Remove the auxiliary TXV assembly mounting bolts.
21. Remove the auxiliary TXV assembly.
22. Remove J 45268-111 from the auxiliary TXV assembly.
23. Inspect the auxiliary TXV for debris. Clean or replace as necessary.
24. Install the auxiliary TXV and auxiliary HVAC module back into the vehicle. Refer to Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement.

Note: Debris may form at the front TXV when flushing the auxiliary A/C System. It is necessary to remove and inspect the TXV to maintain optimal A/C System performance.

25. Remove and inspect the front TXV assembly for debris. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.

Clean or replace as necessary.

26. Install the front TXV. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.
27. Replace the desiccant bag. Refer to Air Conditioning Refrigerant Desiccant Replacement.
28. Evacuate and recharge the A/C System. Refer to Refrigerant Recovery and Recharging.
29. Leak test the fittings using J 42220 .

Flushing without Auxiliary A/C

Special Tools

Note: Flushing is not intended to remove metal from the A/C system.

Flushing is intended to remove the following:

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

Note: Inspect and lubricate the J 45268 fitting O-rings. Refer to O-Ring Replacement.

1. Install the J 45268-7 (2) onto the suction line adapter block J 45268-13 (1).
2. Install the J 45268-8 (3) onto the discharge line adapter block J 45268-12 (4).

Note: Reverse flow refrigerant flush is recommended for desiccant bag failure. Replace the condenser/receiver dehydrator assembly when the A/C flush is complete and perform the following procedure:

Note: Inspect and lubricate the J 45268 fitting O-rings. Refer to O-Ring Replacement.

1. Install the J 45268-8 (2) onto the suction line adapter block J 45268-13 (1).
2. Install the J 45268-7 (3) onto the discharge line adapter block J 45268-12 (4).

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

1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging.



2. Remove the thermal expansion valve (TXV). Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.
3. Install new O-rings onto the evaporator core and A/C lines. Refer to O-Ring Replacement.
4. Install the A/C lines into J 45268-110.
5. Install J 45268-110 onto the evaporator core.
6. Install the TXV line bracket.

Caution: Refer to Fastener Caution in the Preface section.




7. Install TXV mounting bolts and tighten to 3.5 N·m (31 lb in).
8. Remove the A/C compressor. Refer to Air Conditioning Compressor Replacement.




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

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

Note: Install new O-rings onto the A/C discharge and suction lines. Refer to O-Ring Replacement.

10. Install the J 45268-13 to the A/C suction line.
11. Install the J 45268-12 to the A/C discharge line.



12. Connect the J 45268-1 flush filter to the J 45268-7 flush fitting.
13. Connect the blue hose from the J 43600 to J 45268-1 flush filter adapter.
14. Connect the red hose from the J 43600 to J 45268-8 flush fitting.

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

15. Flush the A/C system. Follow the instructions supplied with the J 43600 .
16. Disconnect the red hose from the J 43600 to J 45268-8 flush fitting.
17. Disconnect the blue hose from the J 43600 to J 45268-1 flush filter adapter.
18. Disconnect the J 45268-1 flush filter from the J 45268-7 flush fitting.
19. Remove the J 45268-12 from the A/C discharge line.
20. Remove the J 45268-13 from the A/C suction line.




Note: 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.
21. If you will reinstall the removed A/C compressor, perform the following procedure:

21.1.

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: Rotating the compressor hub assembly when adding PAG oil to the A/C compressor suction port will draw the PAG oil into the crankcase chamber and prevent overflow.

21.2.

Add the total system capacity of PAG oil into the suction port of the A/C compressor while slowly rotating the A/C compressor hub assembly. Refer to Refrigerant System Capacities.

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

21.3.

Add one bottle of J 41447 directly into the suction port of the A/C compressor while slowly rotating the A/C compressor hub assembly.

Note: A new service compressor is shipped with a full charge of PAG oil. Refer to Refrigerant System Capacities.

22. Install the A/C compressor. Refer to Air Conditioning Compressor Replacement.
23. Remove the TXV mounting bolts.



24. Remove the TXV line bracket.
25. Remove J 45268-110 from the evaporator core.



26. Remove the A/C lines from J 45268-110.
27. Inspect the TXV for debris. Clean or replace as needed.
28. Replace the desiccant bag. Refer to Air Conditioning Refrigerant Desiccant Replacement.
29. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging.
30. Leak test the fittings using J 42220 .