A/C System Filtering

 CAUTION: Follow all refrigerant system safety and service precautions as outlined in Section 12-00.

An A/C service kit has been released to provide the necessary equipment and information to perform the new, mandatory A/C system filtering procedure. The filter kit with the service part number suffix A is to be used on vehicles that have a nylon lined A/C manifold and tube (19D734) suction line between the suction accumulator/drier (19C836) and the A/C compressor (19703).

1. To determine that the A/C compressor has failed and must be replaced, remove the A/C evaporator core orifice (19D990) and condenser to evaporator tube (19835), if necessary. Look for a dirty A/C evaporator core orifice or a condenser to evaporator tube containing black refrigerant oil and particles.

2. NOTE: Cap all open refrigerant lines and components to prevent entry of dirt and moisture.

   Remove the damaged A/C compressor and drain the oil into a calibrated container.

3. NOTE: The proper amount of refrigerant oil must be added to the new A/C compressor before it can be installed. The procedure for the FS-10 is given.

   A new FS-10 service replacement A/C compressor contains no refrigerant oil. If the amount of oil drained from the removed A/C compressor is between 85 and 142 ml (3 oz. to 5 oz.), pour the same amount plus 1 (one) ounce of clean oil into the new A/C compressor. If the amount of oil drained from the old A/C compressor is greater than 142 ml (5 oz.), pour only 142 ml (5 oz.) of clean refrigerant oil into the new A/C compressor. If the amount of refrigerant oil drained from the old A/C compressor is less than 85 ml (3 oz.), pour 85 ml (3 oz.) of clean refrigerant oil into the new compressor.

4. NOTE: It will be necessary to transfer the A/C clutch (2884) from the old A/C compressor to the new A/C compressor.

   Install the new A/C compressor. Be sure the compressor mounting bolts are tightened to the proper specification. Check the tension of the drive belt (8620). Adjust, if necessary.

5. Remove the suction accumulator/drier and drain the oil into a calibrated container.

6. Add clean refrigerant oil to the new suction accumulator/drier in the same amount that was removed from the old unit, plus an additional 60 ml (2 oz.) of new refrigerant oil.

7. Install the suction accumulator/drier in the vehicle.

   
   
   
   
   

8. Get the proper service kit for the vehicle on which you are working. Filter kit with the service part number suffix A is used on vehicles with a nylon lined evaporator to compressor suction line (19867).

   
   
   
   
   

9. Remove a length of evaporator to compressor suction line to accommodate the suction filter and install the filter using the clamps provided with the kit. Be sure filter is correctly oriented for refrigerant system flow. Check the label on the filter. On the filter for nylon lined evaporator to compressor suction line, install O-rings (two on each filter tube being sure they are properly seated in the grooves on the tube). Tighten the clamps securely.

10. Install a new A/C evaporator core orifice. If the A/C evaporator core orifice is located in the condenser to evaporator tube between the A/C condenser core (19712) and the A/C evaporator core (19860), replace the condenser to evaporator tube. Refer to Section 12-00.

11. Install a pancake filter in the condenser to evaporator tube between the A/C condenser core and the A/C evaporator core orifice. Be sure the filter inlet is toward the A/C condenser core. Connections can be made using A/C Test Fitting Set D93L-19703-B or equivalent and flexible refrigerant hose of 2500 psi burst rating. Individual fittings are also available.

    
    
    Condenser Core Connections
    
    
    
    
    

12. Evacuate, charge and leak test the system.

13. Check all refrigerant system hoses, lines and the positioning of the newly installed filters to be sure they do not interfere with other engine compartment components. If necessary, use tie straps to make adjustments.

14. Provide adequate airflow to the front of the vehicle (with a fan, if necessary), and set the selector valve at MAX A/C. Set the blower motor (18527) on HIGH and temperature control at full cool. Start the engine (6007) and let it idle briefly. Make sure the A/C system is operating properly.

15. Gradually bring the engine up to 1200 rpm by running it at lower rpms for short periods (first at 800 rpm, then at 1000 rpm). Set the engine at 1200 rpm and run it for an hour with the A/C system operating.

16. Stop the engine.

17. Allow the engine to cool sufficiently to remove the fittings, flexible hoses and pancake filter from the condenser to evaporator tube. (It will be necessary to discharge the system first.)

18. Discard the pancake filter. It can be used one time only.

19. Reconnect the condenser to evaporator tube back into the system.

20. Evacuate, charge and leak test the system. Make any necessary adjustments.

21. Check the operation of the system in all modes.