the black post filter tells you motor has gone just get new motor look on youtube it shows you how let us know if it sorts it
The motors rarely just stop when they go, Id start by replacing the fuse, thoroughly checking the cable for damage, and if that still doesn't start it carefully connect a cable to the chassis cable bypassing the switch and original power cord. At this point if it works then its either switch or cable issue, fit the switch and then test.
If it still doesn't work then assume motor.
It is possible that the carbons have just worn right down that its no longer in contact and a pair of new carbon brushes will solve it, ive had it a few times in the past but more common for it to be a cable issue when it just stops.
Normally a burnt out or worn motor will emit burning smells and slow down making strange noises before dieing completely- but again there is sometimes the case of otherwise.