Atlas SD40 Unpowered 3 rail locomotive coupler help!

If you buy an atlas dummy from the factory, it has an electrocoupler, with a pigtail inside it that is connected to nothing.  So what you're doing, is the same thing that the factory did. If you are powering locomotives, remember to take the center shaft with the worm gear on it too. Unlike some other locos, on atlas locos the driven worm gear shaft is held in by the motor mount. Its not needed on a dummy but you'll need it to transfer power.

Boilermaker1,

Thank you for the input, I appreciate it. If I leave all of the tmcc hardware inside the loco also, would that be helpful to 3 railers also? I have no use for it so not sure.

Thanks,

Kenny B

http://www.3rdrail.com/err-3rdrail/index.html

@Trainman88 posted:

Boilermaker1,

Thank you for the input, I appreciate it. If I leave all of the tmcc hardware inside the loco also, would that be helpful to 3 railers also? I have no use for it so not sure.

Thanks,

Kenny

Depends on the generation of the boards. The older the boards the higher the indifference. If it has ERR boards in it, I'd say pull the boards and sell em.  If they're SAW or EOB boards then you could leave them in there but Im not sure it would add much value.
Leaving the electronics in it without motors would give it some function (lights and couplers), so if you can get out what you need without undoing too much of the harness, it might be worth it to someone to have a “smart dummy”