Jun-Air Compressor Fault

[m_c]

Ah, that looks like an old screw compressor.

Could be the start capacitor has packed in, so the motor isn't producing enough torque to get started. You would have to strip the compressor down enough to find the capacitor(s), then try changing them.

[jamesgates1000]

The motor will start when the compreasor is switched on with no air in the tank, just doesnt top up quick enough to stop the machine alarming out at low air presuure.

[magicniner]

Is the over-length nut that's part of the connection to the cylinder just a nut that's bigger than it needs to be or might it contain a one-way valve?