A few questions, please:
1. Do you know what the amp draw on the loco was ? If it was on a club layout, do you know your loco was the only thing being powered ?
2. Did you receive the instruction book with the loco ? It will be of no help in troubleshooting per se, but does tell you where things are [ more or less ]; for example, have you looked inside the gear box to see if the grease has hardened , etc ?
3. Do you know if the problem is electrical or mechanical at this time ? You can remove the loco body and turn the motor by hand, for example.
4. I would turn the smoke unit and sound off to reduce A draw, etc; I image those controls are on the bottom of the tender ?
5. Do you have test stand rollers or the ability to 'block up' the drivers and run it from clip leads ?
6. Do you have any other MTH locos and are thus familiar with their non-NMRA volt vs speed curves ?
Good luck. With MTH on DC you'll need it.
Best regards,
SZ [ who is a DC 2 rail person with some MTH locos, but none steam ]
