Thanks for the update.
Your locomotive is one of "them".
Lubricate the axle bearings and gears and run the locomotive for your enjoyment.

Here is the service manual pages for your locomotive. http://pictures.olsenstoy.com/1110.htm
Study it and see what the insides of the motor look like. Remember, all the wheels have to come off to open the case to service the motor. Then you have to put the wheels back on straight, and quartered properly, or the rods will bind.

Been there, done that, as they say.

Larry