Athearn DCC conversions will not run

[Colli]

I have 2 older style Athearn diesels, both converted to DCC using the Athearn wiring kit from Digitrax and a Digitrax DH123 decoder. I can program them for 4 digit addresses but they will not run on main line.The headlight is on but the loco wont move. I re- addressed them to 003 for DC and tried again, now they buzz, the light is on but still no movement.
Any suggestions
Thanks Colli.

[jward]

003 is the factory default address for most decoders, on digitrax 00 is the analog address.

that said, athearns require alot more than just the digitrax wiring harness to get them to work well on dcc. to start with, the electrical pickup on them is adequate for dc, a nightmare in dcc. consider hard wiring the decoder to the triuck pickups. the pickup on the athearns at the truck bolster is made by the weight of the frame resting on the truck, not anywhere near reliable enough for dcc. also, stock athearns have sintered metal wheels which get dirty quickly, and don't pick up well enough for dcc. you may want to replace them with nickle silver wheels.

[Colli]

Thanks JWard,  I did finally figure out where I went wrong and have one of the locos up and running, now if I can just find that brush spring, the other one should be O.K. to.