Installing a Decorder in a Rivarossi 4-6-4

[Anonymous]

I'm in the process of installing a DCC decorder into a Rivarossi 4-6-4 Hudson. I have the engine completely disassemble, but I'm a little confused on which wires to contect where. I seem to have more wires on the decoder than I do on the engine.

[orsonroy]

Dig around on the "Wiring for DCC" website:

http://www.wiringfordcc.com/

There are several examples and diagrams on wiring various steam locos, including at least one Rivarossi engine. It should answer your questions.

[cacole]

Most decoders have 9 wires, but you need only 6 wires for track pickup, motor, and headlight. Just cut the other wires short and leave them unconnected. Rivarossi normally used black wires for both motor brushes, and the connections on the motor were at the top left and right corners (looking at the motor from the back). Disconnect the wire from the top right motor brush and connect the decoder's red wire to it. The orange decoder wire connects to the top right motor connection. Likewise, disconnect the other motor wire and connect the black decoder wire to it, and the gray decoder wire to the motor terminal. The blue and white wires go to the headlight. If the motor runs backwards, reverse the orange and gray wires. If you have a voltmeter, check the two black wires after they are disconnected from the motor. The wire that was connected to the top right motor brush should be the right rail pickup, and the other wire goes to the left rail. The motor should already be electrically isolated from the frame.