I am converting an old Athearn diesel loco to dcc and got everything wired up only to put it on a DC track to test it and have absolutely nothing happen. All the soldered connections appear to be good. I checked and rechecked everything. Black wire to headlight bracket, red wire to power clip above front and rear trucks with a jumper between them, orange to top clip of motor and grey to bottom clip. Motor isolated from frame with steyrene. To test that the motor was working (it was before the conversion attempt) I used two short wires holding one end to the track rail and the other to the positive bar of the motor, same for the negative and alas, the motor started spinning. WHen I hold the wires to the track and touch the other ends to the headlight bracket and truck tower clip the decoder sound starts up so I think the decoder is fine. So my theory here is that power is not getting from the trucks wheels to the frame and tower clips. What did I mess up? I didn't remove the trucks during conversion so they shouldn't have been effected. I feel like I am missing something really obvious here. Any help suggestions would be appreciated.
Follow-up...the trucks are still not transferring power as they should but I learned a valuable lesson this weekend (cost about $35). Don't "hot-wire" the motor to test that its working while the decoder is still attached to the harness. I connected a couple wires to the tracks in DC mode then directly to the motor and alas it did turn a little and the speaker came on so I turned up the power and it turned a little more. Thinking maybe the motor just needed to warm up I turned it up some more...after a nice little fireworks display and some smoke from the decoder, I finally decided that was a bad idea. Bye-bye decoder. Hello lesson learned. Thinking that loco, though rarely used, is still 20 years old and probably needs a thourough cleaning and lube. Hoping that with a new decoder will fix the problem. Still concerned about the apparent lack of power from the trucks. The engine was working just fine as a DC only engine so it never crossed my mind that there wouldn't be enough juice to run it in DCC. Maybe my inexperience talking.
Archipapa,
If it is a ATHEARN,BB (blue box), review this:
http://www.mcor-nmra.org/Publications/Articles/Athearn_TuneUp.html
Frank
Zstripe, I did see that article but only after I fried my decoder. Question if you know...would I need to replace the motor? Like I said, its an older loco but was never used that much. Hoping it just needs a little TLC.
I have ran across several Blue Box locomotives where that headlight clip was so loose that the decoder was not getting power from the left rail. Check and see if there is a lot of wobble to that clip. If so, you need to find someplace else to connect the black decoder wire.
That headlight bracket is sometimes not fastened very well to the chassis.
An alternative location I have used on several models is to tin the end of the black wire and put it through one of the motor mount holes, especially when using the newer version of motor mounts that are held in place with screws.
Drill a hole in the top of the chassis and insert a small brass screw - make sure it's in a place that won't interfere with mounting the shell. You can then solder your wire to the brass screw.
Mark.
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