1989 Hoover Logic 1300 (A3790) washing machine functions normally through all washing modes but fails to spin in either 500 or 1300 rpm mode. Drum level pot checked & cleaned ok. Motor brushes checked & ok. Could motor be u/s ? or is this a controller fault ie no spin signal ? N.B. this m/c has been frequently serviced (brushes, level pot, heater, de-sludge...etc) over previous 10 - 15 years.