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] Air compressor oil is standard or synthetic oil made specifically for air compressors. Unlike motor oil, air compressor oil does not contain detergent and typically has lower amounts of carbon, sulfur, an.
[pdf] Heat generated during compression can cause air expansion before intake is completed. Poor cooling performance—whether due to inefficient oil cooling or water cooling —raises internal temperatures and reduces overall intake volume. Air displacement is directly proportional to rotor speed.
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