A portable/towable rotary screw diesel air compressor capable of around 180-260CFM costs approximately $14,000 to $20,000. A heavy duty turbocharged diesel compressor designed for mining, railroad, and heavy-duty construction might cost $25,000 to $30,000 or more.
[pdf] Check whether the oil content in the condensate discharged from the drain valve of the Kaishan air compressor is too high, whether the oil level of the compressor is too high, whether the opening pressure of the small pressure valve is normal, whether the return oil pipe is blocked, and whether the oil separation core is blocked.
[pdf] 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. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere. Check all relays, fuses and electrical connections.
[pdf] 
