The green wire in the motor is connected to the ground pin on the cord. One wire is connected to the 208 pin. And two others are tied together.
What type of plug and receptacle are in use? Is this actually connected to a grounding (U-shaped) prong on the plug?
It would work that way, since the ground is bonded to the neutral (the mid-point of the A-C winding in the diagram above), but actual GROUNDING pins should not be used for current-carrying conductors.
It does sound as though it might be a motor designed for 120 or 240V operation (by altering the windings to parallel/series) which is being undserrun a little on 208V.
