converting bachmann 4-8-4 steam dc to dcc bachmann decoder

[just427]

hi i was woundering if some one could tell me what wires to hook up so i can keep steam function or have it work well loco is sitting still thx justin

[Jim Banner]

The paperwork with the decoder should already tell you which decoder wire (identified by colour) needs to be connected to which locomotive wire (identified by function.)  Your problem will be to identify each locomotive wire by where and what it connects to.  Often you will want to disconnect the locomotive wires and connect the decoder wires in their place.  Be wary of "sneak paths" where there are connections that are unseen but may still cause damage.  One example of a sneak path would be the case where the locomotive frame is used to carry power from the wheels on one side to one contact on the motor.  This type of connection can be broken by isolating (disconnecting) the motor from the frame.  If not broken, such a sneak patch will damage the decoder.

Jim