DCC Install in a Walthers Sperry Rail Service Car

I began by testing the car on a friends DC layout. It is a smooth running unit. I have the newer model where the drive is improved to a geared power truck.

We begin with gathering the required items for the install. The box says nothing about being DCC ready so I assumed this would be a wired decoder install. I used a Digitrax DH163D wired decoder but any similar wired HO or N decoder should work.


I began disassembly by removing the two screws just forward of the power truck.

It turned out that these screws have nothing to do with the removal of the shell! They simply hold the pilot and coupler assembly to the floor. Unless you want to remove these details, it is not necessary to remove these screws.

Several of the bottom details fell off during the process of testing the shell by gently spreading the sides of the shell. It appears they are a simple press fit into the floor of the car. I took note of where they came from and will use a drop of CA to glue them back in place when the install is done.

Using gentle pressure on the sides, the rear of the floor gave way first and then with gentle prying, the forward section of the floor let go.


There are two wires going from the motor to the roof of the car for the headlight. As the picture illustrates, there seems to be a resistor going to the headlight and from that I concluded that this is either an LED or a 1.5v bulb with resistor. Either way, it should be a simple hookup to the lighting output of the decoder.

I removed the side frames of the power truck and then removed the two screws on each side of the motor to release it from the floor.


As the picture illustrates, the wiring is slightly strange. Power is picked up from all 8 wheels and the rear truck’s wires are red and black. There is also a red and a black wire from the power truck to the motor but they are connected black to red and red to black. This is counter intuitive but I assure you the unit was fully operational when tested out of the box in DC. The red and black wires to the headlight match up with the red and black wires from the rear truck.

I cut the wires from the motor tabs and cleaned up the contacts with my soldering iron. This is where I ran into trouble, when I realized I didn’t have heat shrink small enough to use on these wires. Heat shrink tends to be expensive from online shops but I found a good Canadian source for small heat shrink in a variety of colours. I bought it at my local Princess Auto but it is also available from their online store.  https://www.princessauto.com/en/detail/24-pc-1-mm-x-6-1-4-in-colour-coded-heat-shrink-tubing/A-p8292385e

To ensure I wasn’t crazy, I tested the continuity of the wires. On the rear truck the red wire is indeed the right rail and the black is the left. On the front power truck the black is the right rail and the left is red. Why is a question that cannot be answered.


I temporarily hooked the power truck to my DCC system to ensure I had the motor wired properly for forward and reverse operation.


I used ½ inch of heat shrink to insulate the splice of the decoder wire to the front and back pickup wires.


I hooked the white wire (F0 Forward headlight) to the headlight lead that appeared to have a resistor on it and the blue (common) wire to the other lead. On the track everything worked, but I could not get the light to light. I cut the wires and measured the voltage across the white and blue wires. Nothing. Hmmm. Time to read the manual. The manual indicates that for a single headlight locomotive the white and yellow wires should be connected together. Powered back up and voila! There was 12v across the white/yellow and blue wires. The manual is your friend.

With everything hooked back up I tried again. Still no joy with the headlight. Going against my better judgement I hooked to blue common wire to the headlight lead with the resistor and the white/yellow wire to the other lead. JOY we have light. Not sure what is going on here but apparently there is some kind of directional lighting?


Both function wires and white wire attached and heat shrinked.


I used a longer piece of large heat shrink to keep the wires together. Here is the unit ready to go back together. As noted earlier I removed the wire tie near the motor and used some Kapton tape to keep the wires in check.


Here she is ready to check some rail!



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