N Scale Locomotive Maintenance

Cleaning the Wheels

• Your N scale locomotive will not generally require much maintenance to keep it running smoothly. The largest danger to normal operations is from dirt and debris. Avoid most locomotive cleaning by keeping your track clean and clear of any foreign materials. Most of the dirt that gets past the track cleaning and into your locomotive will tend to accumulate in the locomotive's wheels.
  To clean your wheels, take a cotton swab or pipe cleaner and dip it into rubbing alcohol. Use the damp swab or pipe to gently scrub the wheels, removing the dirt. While running your locomotive on a clean track will cut down on the frequency of wheel cleaning, you'll still need to provide maintenance every six months to a year.

Cleaning Gears

• Over time the parts in an N scale locomotive will begin to wear out. When cleaning the wheels, take a moment to do a quick inspection of your locomotive's parts. The only way to get a good eyes-on inspection is by disassembling the locomotive. Remove the body from the locomotive's chassis and examine the gear system. Check for dirt or debris, and if present clean the dirt from the gears.
  It may be necessary to disassemble the gears in order to clean them, but you should avoid doing so if possible, as reassembling and aligning the gears is a difficult process. Once the gears have been cleaned, apply a small amount of plastic-compatible lubrication using the tip of a toothpick. Be careful when applying lubricant as too much will only attract dust and gum up the works, necessitating another cleaning before the gears wear themselves out or the engine becomes damaged.

Motor Maintenance

• When lubricating the gears it's also a good idea to lubricate the motor brushes in your engine. The motor brushes are small carbon slugs located between the motor terminals and the communicator. They help provide the electrical connection between the two parts and are subject to a great deal of friction during operation, wearing down as the motor runs.
  If your engine was running erratically before maintenance, it may be due to the brushes wearing too far and no longer providing the electrical connection. In such a case the brushes will have to be changed. New brushes can be found at local hobby shops that sell model locomotive parts or at online retailers.