Quincy 1968 QT-5 air compressor - air binding after bleed down

by tom
(charleston , Me.)

I have a 1968 QT-5 air compressor. After the pressure goes below 60psi the compressor tries to start but it is bound up. If I turn the throw switch off and on she kicks in and builds to pressure.Electrical or pressure valve issues?

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Bill says...

Tom, when the compressor runs to full pressure and cuts out, does the unloader work?

Or, does the compressor start fine with no air in the tank, but won't start at normal cut in pressure?

Bill