Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any ‘hiccups’ (be sure to completely shut down the air compressor!). Check the isolation of the motor winding.
[pdf] Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings.
[pdf] Rotor clearance issues or debris can lead to metallic contact sounds Loose or worn belts squeal or howl, especially under load Airflow pulsations, valve leaks, or turbulence create hissing or whistling Bolts, nuts, and mounting pads loosen over time, amplifying noise
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