When I was running my little Nn3 Mogul at the train show a couple of weeks ago it got pretty hot and then stopped working. The motor has been sort of finicky lately so I figured it was probably time for some attention. It is a 3 pole and I wanted a 5 pole anyway, so I decided to swap it out.
Swapping a motor in a Marklin 2-6-0 chassis is not a simple thing to do, but with the proper tools it can be accomplished. The motor is not removed as a single unit as it is on larger locomotives, that would be too easy. Instead the magnets in their housing have to be removed and then the gear pulled off the armature shaft. Then the armature can be lifted out and swapped with the 5 pole motor. The gear is then pushed back onto the new armature shaft (the article uses a small hammer but I used a C clamp) and the magnet housing reinstalled.
The brushes for these motors are also separate, and when I opened the package to install them I found one of them defective. A quick email to ajckids, where I got the motor and brushes, netted a new set sent immediately and without further charge.
I put the brushes on and attempted to run the locomotive and had an odd little problem; the rotating commutator pulled the engineers side brush backwards out of position. Running the locomotive forward did not pull the firemans side brush out, but every time it ran forward the right side brush pulled backwards. It took a bit of bending to hold the brush in place, but it finally stayed.
Brushes installed and wheels cleaned, the motor works beautifully. The locomotive no longer needs to be started by hand, the application of starting voltage is enough all by itself now. It also runs quieter and smoother at lower speeds, all of that makes it a much more enjoyable locomotive.
I spent the evening running it in with assorted consists, and I am pretty confident in saying it is ready for the next show.
The Great Train Extravaganza 2021 (Video)
3 years ago