Switching DCC Decoders in Nscale?

[pschuman21]

I switched out a Dash 8-40BW Lenz decoder to a B30-7. I just moved the DC board form the  B30 and into the Dash8. In the Lenz Manual for the Decoder "063XF" (I think thats the right number off the top of my head) anyhow, the same Decoder is used for multiple Atlas Locos. So in theory it should work. When I made the change, which I did very carefully, the two swapped pretty easily. So before placing the shell back on I put the loco on the Programming Track too renumber it. That seamed just fine so far, but when I went to run the loco it didn't move. The lighting functions worked but the loco didn't want to move. I switched back the Decoders a few days later, and all worked fine. Can anybody help with this problem? Leave a question if you need more detail, Thanks.

[river_eagle]

motor pads on bottom of board are not lining up with the tabs/wipers and making a solid connection.

[Vail and Southwestern RR]

In some loco/decoder combos the decoder board is not quite thick enough for the motor pads to make good contact.  A little shim, or tinning the pads with a bit of solder can fix that problem.

[pschuman21]

Ok, Thanks for the help. I'll try your ideas as soon as I have some free time. Thank again.