Hi whitepond
From your description, it sounds like the motor shaft is spinning but no power is transmitted to the wheels.
Remove the shell and place the loco on the tracks, power it up and see whets going on..
Maybe worm is not engaging to the truck gear.
Or perhaps worm or truck gears are not held fast to their respective shafts.
Open it up and report back as to what you observe.
From your description, it sounds like the motor shaft is spinning but no power is transmitted to the wheels.
Remove the shell and place the loco on the tracks, power it up and see whets going on..
Maybe worm is not engaging to the truck gear.
Or perhaps worm or truck gears are not held fast to their respective shafts.
Open it up and report back as to what you observe.