It's Alive!

I went to the LTS (Local Train Store) on Saturday and picked up a Digitrax DCC Decoder with the Athearn Harness.

I did a couple of things to the motor before I installed the decoder.


First, I disconnected the drive shafts and started the motor running. Then I took a file to the commutator, to clean it up an polish it a bit. You can see a bit of difference between 6773's (top picture) and another unit that is waiting to go through the shop.



Ugly nasty commutator :(


After that, I started to install the decoder. the instructions were helpfull, except for the text about the actual installation, which is for another type of wiring harness. I worked off the diagram, and this what I came up with.

1) Attach the red wires/clips to the L brackets coming out of the trucks. I did this so the pigtail end was at the rear of the loco.

2) Attach the black wire/clip to the headlight post. On mine, I had already had extracted the headlight in preparation for one that does not light up the entire cab.

3) Remove the motor from the frame

4) Cut a narrow piece of electrical tape to cover the space between the motor mounts in the frame. I didn't actually do this on mine, but I should and you should to!

5) Carefully remove the bottom motor clip, making sure that the spring and brush don't make a run for it. At this point, for a smoother running motor, you can cut off about one third of the spring. This reduces the pressure of the brush against the commmutator and let's the motor run more efficently. Attach the Gray wire/clip to the bottom of the motor.

6) Repeat step 5 with the top clip, attaching the orange wire/clip to the top of the motor.

7) Put the motor mounts back on the motor and reinsert into the frame.

8) Insert the drive shafts into each end of the motor, and place the worm end back into the truck and replace the cover.

At this point, the unit is ready for a test run. Place it on a DC powered track, and slowly increase the voltage. If the unit does not run, IMMEDIATELY remove it from the track. Make sure that your motor is fully isolated from the frame. The decoder I got, a Digitrax DH123 can tell if the motor is not isolated, and will shut it's self off. Older decoders will eventually release the magic blue smoke if they are on a non isolated motor.

My test run was a success, so I started to put it back together.
I started by running all motor and power related wires along the top of the motor and taped them down with electrical tape, making sure that they do not interfere with the drivetrain.

I then made a coil of the headlight wires (yellow, white, and blue) because I am not quite ready for the headlights yet, and a coil of violet and green wires. These last two aren't used by the DH123, but I left them in place if ever get a decoder that can use them.



I then placed the coils on top of the decoder, and placed the whole thing into the roof of the shell, and reattached the shell to the engine. I then ran the unit with the shell on. I found that it was binding up on curves, so I removed the Dynamic Brake hatch and pushed the decoder up closer to the roof of the unit, and that took care of the problem.

Now that she's running pretty good, the next step will be to pretty her up. Stay tuned!