Old Elu Machine not working

Thermal cutout somewhere? Perhaps it's lacking in lubrication and having to work harder than normal, which is over-taxing the motor? It could be it's a thermal fuse rather than a resettable breaker. Could be in the latching part which is why it's failing to stay on?

Theo

Is it an induction motor machine?

Many of these have a start winding and a start capacitor that is controlled by a centrifugal switch. At power on the switch is closed such that the start winding is in circuit. However once the motor gets up to about 80% speed, the switch should open and disconnect the start winding. If that has got stuck in the closed position, that could explain the overload due to the extra winding not being switched out.

Good explanation here:

The most common cause for woodworking machines failing to start is sawdust in the switch.

The contactor, has a set of contacts, which maintain the energised state of the coil until the stop button is pressed. I would check that sawdust is not preventing the maintain contact making, or the coil armature moving the contacts fully. Additionally, check the stop button is not itself jammed partially in by sawdust.