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If you do replace one of these motors 4 things to be aware of.
1. A hidden screw dead center under do not remove foil/sticker to separate the cases.
2. Drain off or discharge all static from your body when working on it. Lots of sensitive stuff in that box. No need to be touching that area anyway to replace motor.
3. When putting in the motor make sure the output shaft that the plastic adapter to aluminum tube screws on is spinning CCW looking at it straight on. This will keep the tube screwed on in operation and not unscrew it. If it isn't flip the motor to circuit board 180 deg re-solder it and it should work. (This is a DC motor if wires hooked up one way it runs CC, hook them up the other way it runs CCW)
4, As soon as you get the motor back in the dispenser unit loosen all 4 screws that hold it on and gently screw in the aluminum tube. This will center the motor on the works to the tube, then slowly tighten each of the 4 screws down. Remove tube and install the motor / dispenser back into the case. Install the 3 screws that hold it in place, put tube back in from front and it should align perfectly to screw in place. Lightly screw the tube in (you don't want to strip those tiny little gears or plastic adapter to motor).
Like I said earlier a motor that is a little slower seems to work better than the original for me, I wouldn't hesitate to put in a 100 rpm model in especially for lighter loads and super accuracy.
It still wouldn't be that slow at dumping charges in my opinion. Good luck.. HB