I've had one for about 25 yrs (my parents bought new) & the blue sparks come out of exhaust. Is it time to change the brushes or do I need to replace the motor?
Not a good sign. At minimal new carbon brushes. At worse, armature and so new motor. You'll know for sure when you take apart and examine. If you continue to run/use especially if just the carbons, you'll do futher damage. Possibly, possibly, some dirt caught between the brush contacts and commutator [armature]. Check the likely causes: bag, filter that may need cleaning/replacing.
Carmine D.
