Jamie,
Since this is a cabinet machine it lays on it's front side when in storage. The motor is right on top in the path of dust, lint, particulates and even pet hair. All this and old oil will collect inside the vent holes of the motor and will burn off when you start using it. Even portables do this, but to a lesser extent.
Do a visual check on the wiring from where it enters the motor to the plugs, to the foot controller, and under the machines body. If it looks good, oil the motor then run it wide open for a while. You'll hear it change pitch as it cleans out the dirt and debris. (These instructions came from my LSMG)
Belts can be had at your LSMG or Sew Classics as well as other places.
Joe