The air vacuum which runs most of the Blue Box’s mechanical functions is generated by the turbine. The turbine consists of a 3/4 hp electric motor connected to a series of impellers. The vacuum generated by the turbine is connected to the spindle which in turn distributes it to the rest of the trainer. The exhaust air empties into a tail pipe. We avoided total disassembly, but rather cleaned and lubricated the unit, and checked the brushes. Two large brushes are held in with thin round hard rubber disks. Care needs to be exercised when removing the screws to check the brushes because it is easy to damage the retaining disks. There is an access panel at the rear of the motor which allows easy cleaning of the commutator — ours was filthy. We cleaned with contact cleaner, and sparking was reduced considerably. We also removed the rear motor plate and cleaned out all the old grease which was hard and caked on. We put fresh grease in front and rear motor bearings.
