Compressor HVAC: Testing and Inspection

A/C Manifold And Tube Leak Test
1. Tighten the manifold retaining bolt to 18-23 N.m (14-16 lb-ft).
2. Add refrigerant to the system if necessary.
3. Leak test the manifold O-ring seals using Rotunda R-134a Automatic Calibration Halogen Leak Detector 023-R1003 or equivalent.
4. If no leaks are found, the manifold O-ring seals are good.
5. If a leak is found at the A/C manifold and tube and the manifold retaining bolt is tightened to 18-23 N.m (14-16 lb-ft), install new manifold O-ring seal. Repeat the leak test.





External Leak Test
1. If the A/C compressor is on the vehicle, discharge the system using the procedure described in System Discharging and Recovery. Discharging and Recovery Remove the A/C compressor from the vehicle.
2. Remove the manifold retaining bolt and remove the A/C manifold and tube from the rear head of the A/C compressor. Install A/C Pressure Test Adapter T94P-19623-E on the rear head of the A/C compressor using the existing manifold retaining bolt.
3. Connect the high and low pressure lines of a manifold gauge set to the corresponding fittings on the A/C Pressure Test Adapter T94P-19623-E.
4. Attach the center hose of the manifold gauge set to a refrigerant container standing in an upright position.
5. Hand-rotate the compressor shaft 10 complete revolutions to distribute the oil inside the A/C compressor.
6. Open the low pressure gauge valve, the high pressure gauge valve and the valve on the refrigerant container to allow the refrigerant vapor to flow into the A/C compressor.
7. Using Rotunda R-134a Automatic Calibration Halogen Leak Detector 023-R1003 or equivalent, check for leaks at the compressor shaft seal and the compressor center seal.
8. If a shaft seal leak is found, install a new shaft seal. If an external leak is found at the center joint of the A/C compressor, install a new A/C compressor.
9. When the leak test is complete, recover the refrigerant.
10. Install the A/C compressor on the vehicle.
11. Leak test, evacuate and charge the system. Observe all safety precautions.





Rotating Torque Check
The rotational torque of a used A/C compressor should be checked if excessive drag is suspected.
1. Recover refrigerant. Observe all safety precautions.
2. Remove A/C manifold and tube from A/C compressor. Use care not to allow dirt to enter A/C compressor.
3. With the A/C clutch disengaged, rotate the compressor shaft and note the torque required to rotate the shaft one complete revolution. Do not measure the starting torque.
4. If the rotational torque exceeds 10 N.m (7 lb-ft), replace the A/C compressor.
5. If the rotational torque is less than specified, excessive drag does not exist in the A/C compressor. Install the A/C manifold and tube and leak test, evacuate and charge the system.
6. Check the system for proper operation.