The motors are seal unit bearing types, they can not be rebuilt, typically the lower condenser fan motor's a 9-watt CW/120 volts ( CW=clock-wise rotation) while the upper evaporator unit is 6 to 4 watts , CW/120 volts, you can use a larger (higher wattage) 9 watt motor for the evaporator it will function the same a lower power motor, however the higher the wattage (power) the more torque the motor has & this can cause it to be noisier than a smaller wattage unit, ( it may cause a "thrumming" )
A note on Rotation: most motors use in soda machines for the condenser are CW/clockwise as viewed from the rear or "lead end" side of the motor, & they are matched to the same rotation fan blade, they "pull' the air through the condenser coils. when in doubt, check your old motors back plate, most evaporator motors are also CW rotation, like on a Vendo machine where the fan pulls warmer air in the front of the coils & pushes it up along the back wall of the bottle compartment, there are noted acceptations such as certain Cavalier machines where the motor sits on top of the evaporator, these are marked CCW/counter clock-wise...always check your old motors rating plate.
the higher the rated wattage of a unit bearing motor means it can spin a larger diameter fan blade assembly without "motor slipping" & quickly over heating itself, while a smaller sized fan blade on a too large or a motor may be caused it to "whip" the air & be extra noisy & vibrate the mounting support.
conversely, If the motors wattage is under rated ( too small wattage-wise) for too large diameter of a fan blade, it will stall & quickly over heat itself.
I typically use a 9-watt for the condenser & a 6 watt for the evaporator.
Funny how something seemingly so simply can turn into an engineering project...