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First, clean the wheels, roller pickups and track with Naphtha as has been written above.

Now you have to do some regular maintenance to the loco which requires you to disassemble it.
You will need to take the loco completely apart to get the boiler shell off to get at the motor.
Once that is done, remove the brushplate to expose the armature and the copper commutator. Don't lose the small brushes that fit in the brushplate tubes. If the brushes are very worn, they may need to be replaced.

Get some Q-Tips, dip them in Naphtha, and clean Everything- brushes, brushplate and commutator. When done, reassemble the motor.

The next item to tackle is the E-unit. Apply power to the loco, and watch the E-unit to see if it cycles properly. Look at the 2 sets of copper contacts to see if they are in good shape and making contact with the drum. To service the E-unit properly you need a special tool to take it apart and lots of patience. Inspect the drum and contacts and replace any bad parts. Using Q-Tips and Naphtha, gently clean the contacts and drum, then reassemble the E-unit. This is where the patience come in, getting all the parts aligned and snapping the E-unit back together.

Next, lightly oil all wheel bearings and both ends of the motor armature, and lightly grease the gears.

After this is all done, your engine should operate and run like new.


Larry