While working on the train today, I decided to get an Athearn RTR Dash 9 ready to run on the layout. Now this is a DCC ready unit and I decided not to put sound in it so this should be quick work, right? Yea, right. I opened the loco and installed a NCE 15SR decoder. Easy and straight forward enough. Put Kadee’s on, since I had it apart anyway, and re-assembled the loco. Put it on the track, called up address 3 and walla! Nothing. Humm… Then it started to move, sort of. It ran very jerky and the rear light would come on and off in forward. And it would derail. The wheel gauge was a bit tight, not unusual, but the jerky running was pretty bad and it growled.
The decoder was new and I had cleaned the communicator when I had it open so I figured it had to be a continuity problem. I figured the growling was a bit of flash or something in the gears.
After opening the gears and removing some loose flash (shocking isn’t it) and checking the wiring, it ran a bit better and the growling was mostly gone. After much tinkering, I finally bit the bullet and took the loco apart. I ended up having to strip the trucks and clean the gears, all of them. I check the trucks and lo and behold, no continuity between the wheels of the rear truck and the frame and little from the wheels to the center post. The front truck wasn’t much better. I had to file the metal side frames where the bronze wheel bearings sit to remove the paint and twist the rivet that connects the body contact to the side frames to get a good connection. I filed the frame bolsters clean at the same time. Since I was in the area…I unskrewed the small copper contact that leads from the frame to the light board. You guessed it, it was sitting on painted frame, so the only electrical transmission was through the skrew. I filed the area under the contact clean too.
So, after several hours of