How to convert Bachmann Class J Norfolk & Western 608 (53252) to DCC

This guide covers the Bachmann USA Class J 4-8-4 steam models:

• Bachmann USA Class J 4-8-4 608 in Norfolk & Western black livery (53252)

It may also be suitable for other models with a similar chassis and motor arrangement made by Bachmann USA.

Step 1 - Remove Tender & Body

Detach the tender and put it to one side. Remove the screw underneath at the front of the loco, and lift the body off.

Desolder the pickup wires that come from the rear dolly wheels.

Remove the large screw in the top of the chassis block (near the front) and lift the top half of the chassis off.

Step 2 - Modify Lighting

Remove the screw holding the two upper chassis halves together, and pop the bulb out.

Bend the legs back straight, and trim them down a little. Solder a blue and white wire to the legs, and cover with heat shrink tubing.

The bulb is 12V, so doesn't need a resistor. Refit the bulb, and put the two halves back together.

Step 3 - Modify Motor Wiring

Pop the motor out, it is held in by the contact springs on each side. Remove the plastic motor shrouding.

Solder an orange and grey wire to the motor terminals.

Add some Kapton tape to the motor's plastic shrouding so the motor terminals can no longer touch the chassis. You can also mill away the chassis if you prefer, however you will then need to glue the motor in place as there won't be anything left to hold it in place.

Refit the motor and fit the upper chassis part back onto the lower part, and put the screw back in.

Step 4 - Connect Pickups

Note how the wheel contact metal 'prongs' fit into gaps in the upper section. To improve this arrangement for more reliable DCC running, solder a wire from the rearmost contact 'prong', and run it to the tab at the back of the loco. We'll join all of the pickups for each side at these tabs, then run new wires to the decoder.

Reconnect the dolly pickup wires to the chassis tabs.

Solder a red wire to the tab on one side, and a black wire to the other side.

At this point, you will have six wires to run to the decoder: red/black, orange/grey and blue/white. Using a multimeter, test there is no continuity between any of these wires. This will prove that you have fully isolated the motor and the bulb from the track pickups.

Step 5 - Connect Decoder

Route the wires towards the front of the loco, using the gap between the chassis halves and some tape to hold them in place.

Solder the six wires to the decoder.

Fix the decoder to the front of the chassis (just above the lights) using some Kapton tape, making sure that the decoder cannot make contact with anything metal.

Step 6 - Programme Decoder

As manufactured, the front light is on regardless of the direction of travel. By default, most decoders will only illuminate the front light when the loco is moving forwards.

To change this, refer to your decoder manual to map F0 to control the front light when travelling forwards and backwards.

For an ESU LokPilot 5, this can be done by setting CV31 = 16, CV32 = 8, CV273 = 1.

Refit the body and the screw at the front underneath, and re-attach the tender.