problem with lionel #500 hobby shop

Without any particular knowledge of this hobby shop, if you're just trying to find out, generally, if an electric motor is good or bad, use a dvm connected to the motor input leads to see if there is voltage present. If there is, then the motor could be your problem. If there is no voltage getting to the motor, then the motor could still be bad, but your problem starts elsewhere up the line.

After years of storing the #500 Hobby Shop in its original box, I decided to find a space for it on my layout.  Years ago after purchasing it, I did ensure that it worked, which it did and then re-boxed and stored it away.   A few month's ago when I connected the accessory to the layout, the motor did not run smoothly and so I immediately thought that the motor was bad and replaced it.  Prior to reassembling the accessory, I tested the motor several times with a 9V transistor battery and the motor ran very smoothly and powered the three sets of miniature trains around the hobby shop. Once I reconnected the device pursuant to the Lionel instructions, only the lighting worked but the motor did not turn on.  In my short conversation with dealer that sold me the accessory, he mentioned that the Hobby Shop accessory must have a circuit board that converts the electrical current so that the motor will run on AC power.  I tested the theory by detaching the motor from the wiring of the accessory and hooked  it up to an ordinary 9V transistor battery, it ran fine, it's only once I spliced the motor wires back into the accessory wires it failed to run at all.  Therefore, to test your motor follow what I did with the 9V battery and if works, you have a good motor. I believe there is may be a way to potentially by-pass the mother board altogether and run the motor on separate power source but I am still researching this alternative.