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So what i have is two Athearn SW 1500 locos. I just recieved one in the mail off e bay. My problem is that if i try to run them together on the track they want to go in opposite directions. I am guessing its a polarity issue but what i would like to know is how to fix it. Thanks in advance Tony
 

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are these trains DCC or DC. If DCC then you will have to reprogram one of the loco's to go in the direction of the other one. If DC then the wireing for one of loco's is backwards cuasing it to go backwards instead of forwards.
 

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They are older BB dc locos. i see no wires to swap it looks like the pickup is on the bottom of the motor. Just not sure how to swap it
 

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no i mean some one could have rewired the locomotive and when they re assembled it they either ment to assemble it that way or screwed up. if you take the plates off that hold the brushes and springs in you can just swap them but be very careful not to loos the springs and brushes.
 

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On the Athern BB locos the motor gets current through the frame and the upper bar. There are two locations that the prior owner could have changed this. They could have modified the trucks to pick up the opposite rail or they more likely modified the motor as previously said. There is a third option (the easiest to reverse). If the motor was modified to be isolated from the frame then the frame and upper bar could be connected to opposite poles on the motor without any changes to the trucks or the motor itself.
 

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Discussion Starter #7
i also thought about swapping trucks but cant seem to get them out of the framework. It seems all you do is push the tabs in but cant seem to get them to release
 

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When looking down on a DC loco, the left side should be Positive, right Negative, any loco, at factory. Reverse polarity will cause reverse operation.
 

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It is a very good comment. I have never gotten to figure out the standard on the polarity of HO rails. Thanks. Also I read the thread and the eaiest way to reverse polarity is to flipp the axles in the trucks. This places the insulated wheel on the other rail thereby reversing motor polarity.

I am not even sure if all my engines are in sync.:rolleyes:
 

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When looking down on a DC loco, the left side should be Positive, right Negative, any loco, at factory.
Neat ... I had assumed there was some standard, but I didn't know which way it went.

I assume your standard description is for forward direction?

TJ
 
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