in the model I have, the metal motor case touches the frame. how do I isolate the motor for DCC operation ?
To isolate the motor use black electrical tape at the base of the motor where the motor touches the metal frame. The black tape will isolate the motor from the frame. Then you can start DCC coding the orange wire to the top of the motor and the grey to the bottom of the motor (same as Athearn). Im assuming you dont have a board inside the loco.
Good luck and let me know how it works out.
Scott11,
To add a little to curtisnu’s suggestion, if there are screws involved in holding the motor to the frame/chassis, make sure they are non-conductive, preferably nylon. Otherwise, you haven’t electrically isolated the motor from the chassis. Plastic screws may not be strong enough to hold everything together long-term. Good Luck.
Mark C.