I bought a used GW GP20 off of Ebay a couple of months ago for a fairly decent price. What I’ve noticed however was that it runs the opposite direction of all the other locos. My layout is DC. So if the power pack is set on foward the loco runs in reverse and when in reverse it runs forward. It can be a bit of an annoyance because right now I got a double main line and running both lines off one powerpack. So my intentions my be to run one train one direction and the other main line the other direction but if i want to sue this engine it runs the same way as the other engine. What could this be???
Remove the shell and reverse the wires to the motor. The seller probably reversed the wiring to the motor so it could be ran backwards as the second unit in a consist.
Years ago my sons Bachmann did that right out of the box. I wasn’t into doing much in the way of repairing or changing then (still reluctant), but it does happen right from the factory. If you only have one loco, you never notice.
I’d say reversing the wires should help.
In DC it made no difference which way you put the loco on the track, they go the same direction (most of them), all you had to do was turn the loco around to have it run with the other hood forward.
I’ve bought several used Athearn engines years ago and all was “wired to mu together in the proper direction” so sayth the seller with pride. I held my laughter. It was a simple matter of flipping the trucks around to fix the problem…
The way Athearn BB locos work, yes, flipping the front and rear trucks actually does change which rail pickup goes to which motor lead. Since there are no wires, this is actually super easy to do. On a clone type loco that has repalced the top clip with wieres, it wouldn;t be as easy, easier to just change the wires.
Think about it - if the right side of the truck is the red wire with the loco facing forward, to swap the trucks you need to rotate them 180 degrees. So now the red wire would be on the left side of the loco. On a loco that uses wires from the trucks to motors, generally you’d have to disconnect the wires to do this, so yes, easier to just change which wire goes where. On the Athearns with no wires, that is pretty much the ONLY way you can do it, since there are no wires to switch. Just pop off the top clip on each truck that holds the worm (don’t lose the bearings!) and the trucks unsnap, flip around and reassemble.
LION SAYS… Left rail is (-) and Right rail is (+), locomotive will move in correct direction.
In DC operation, only the track polarity controls the direction of the locomotive no matter which end has the little “F” painted on it. Your reversing switch is not FWD and REV, but rather EAST and WEST, and it cares not which end of the locomotive is pointed in which direction.
LION does not even have reversing switch on his layout. Subway trains NEVER run backwards.
To change motor “leads” on a Athearn BB engine you would need to disassemble the drive and rotate the motor 180 degrees since the frame is the ground… Simplest way is to turn the trucks 180 degrees.
If the BB engine had the metal strip replace with wire then,yes,reversing the wires would be the best way.
However,in this case the previous owner reverse the trucks to get the locomotives to “mu in the proper direction”.
In a DC engine, provided they are all wired correctly, you don’t have to change ANYTHING to mu any number of engine in any configuration.
Place ten DC engines on the track and turn on the throttle, they all move to the right. Turn half of them around, turn on the throttle they all STILL move to the right !
If any of them don’t, then it’s wired backwards. The only way to fix it on an Athearn blue box is to swap the trucks front to back. You can’t turn the motor around as it only fits one way. Any other engine where the motor is wired to a board, the two wires to the motor need to be reversed.