May also be the fan element if it has one. Sometimes they bend out of shape and catch on the fan blades.
Lincoln Appliance NZ
November 2011
sounds like mechanical failure of the motor bearing or something related.you could try removing motor and greasing up front/rear impeller shaft bearings with thermal grease ,but on inspection you may find a collapsed bearing,.expect to pay around 70 quid for a good bosch motor .
mech monster
November 2011
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