Check hydraulic oil on sight level gauge on hydraulic tank, pumps would be making noise if oil level is low. Make sure all hoses are connected properly and not damaged. Check couplings and make sure they are plugged in properly.
[pdf] It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running.
[pdf] Lishui Fucai Electromechanical Equipment Co., Ltd. has been deeply engaged in industrial products such as screw air compressors, air coolers, factory cooling and ventilation equipment for more than ten years.
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