first, start by trying to see if theres anything stuck inside the engine or the spinner, or if it seems stuck. wich is the most likley case. Because by the sounds of it the Automatic Detector stops it from spinning when something is preventing it from spinning, to prevent the engine from overheating or blowing.
Tristan
July 2007
my first assumptions.
1.the engine is blown or going out, in wich case replace the engine or the machine.