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Compressor HVAC: Testing and Inspection

COMPRESSOR ROTATING TORQUE CHECK

NOTE: The rotational torque of a used compressor should be checked if excessive compressor drag is suspected.

1. Recover the refrigerant from the A/C system. Observe all safety precautions.
2. Remove the refrigerant hose and the manifold assembly from the compressor.

CAUTION: Use care not to allow dirt to enter the compressor.

3. Remove the compressor from the vehicle. With the compressor clutch disengaged, rotate the compressor shaft and note the torque required to rotate the shaft one complete revolution.

NOTE: This is not the starting torque.

4. If the rotational torque exceeds 10 Nm (7 ft lb) replace the compressor assembly.
5. If the rotational torque is less than 10 Nm (7 ft lb), excessive drag does not exist in the compressor. Install the compressor, the manifold, and the hose assembly. Leak test, evacuate, and charge the A/C system.
6. Check the A/C system for proper operation.