The noise of the compressor
When checking the air conditioning system in the presence of noise, you must first define the conditions for the occurrence of noise. These conditions are the weather, vehicle speed, the movement of the car with the gear engaged or coasting, the engine coolant temperature or other special conditions. The noise is heard when the air conditioning system may occur in other units and units of the car. For example, sounds like to publish a front bearing or connecting rod can be caused by the loosened screw connections, weakened brackets or incorrect assembly of the clutch. Check the tension of the ancillary drive belt (power steering, alternator and compressor). Incorrect belt tension can cause a misleading noise when the compressor is running and there is no noise when you turn off the compressor clutch. Drive belts at different engine speeds, and depending on the tension of the belt may produce unusual noises that are often mistaken for mechanical damage in the compressor.
1. Select a quiet area for testing. Several times on and off the compressor to determine the compressor noise.
2. Tighten all screws on the air conditioning compressor and adjust the compressor belt tension. Check for loose coupling coil (there should be no rotation or wobble).
3. Inspect cooling hoses to the absence of friction or backlash, which could cause abnormal noise.
4. Check the amount of refrigerant.
5. Double-check the noise from the compressor in accordance with step 1.
6. If noise is present, loosen compressor mounting bolts and re-tighten the tightening torque given in the specification. Repeat step 1.
7. If the noise continues, replace compressor and repeat Step 1.