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] Though the oil free type compressor design method is used for twin-screw steam compressor, the bearings and synchronous gears still need lubrication by pressured lubricating oil. If steam leaks into the l.
[pdf] Fasten head end of cylinder to cylinder service stand. 2. Remove line (B). 3. Pull rod out so piston is against rod guide. 4. Connect rod to a hoist using a lifting strap. 5. Remove cap screws (A). 6. Pull rod, rod guide and piston from barrel.
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