Bachmann Message Board

Discussion Boards => Large => Topic started by: jrmelton43 on October 17, 2017, 10:44:44 AM



Title: Polarity in Big Hauler
Post by: jrmelton43 on October 17, 2017, 10:44:44 AM
I replaced my original Big Hauler chassis with a new chassis and then reinstalled the body. Runs great, except the polarity is reversed.  It runs the opposite direction of all my other locos. How do I reverse the polarity?


Title: Re: Polarity in Big Hauler
Post by: Loco Bill Canelos on October 17, 2017, 07:56:07 PM
Hi JR,

Most, but not all Big Hauler 4-6-0's have a polarity switch behind the smoke box door on the front of the locomotive, but since yours apparently did not you will need to reverse the wires leading to the motor.  You can do this right at the motor or trace the motor wires back to a convenient spot and cut and swap the wires there.

Most of the replacement chassis I have seen have the long red and black leads from the motor which are meant to go up to the polarity switch behind the smoke box door.   if your body has the switch they should go to the center leads on the DPDT switch.

Hope this helps, but if not post a photo showing you connections and we can try to be of further help.

Good luck with the fix.

Loco Bill

 


Title: Re: Polarity in Big Hauler
Post by: jrmelton43 on October 17, 2017, 09:01:23 PM
Thanks! I'll let you know how this goes.


Title: Re: Polarity in Big Hauler
Post by: OldNoob on October 18, 2017, 08:17:46 AM
I just unscrewed the switch and fliped it around. ;)


Title: Re: Polarity in Big Hauler
Post by: jrmelton43 on October 18, 2017, 04:21:10 PM
Which switch?  Isn't the switch that's behind the door in front of the smokestack for turning the smoke unit off and on? There are black and red wires going to the front wheels. Are those the ones that could be reversed? I'm not very savvy about this stuff!!!


Title: Re: Polarity in Big Hauler
Post by: Loco Bill Canelos on October 19, 2017, 09:55:19 AM
some Big Hauler 4-6-0's have only one switch behind the smoke box door, if yours has only one switch it is for smoke, and your old Big Hauler does not have a polarity switch.  MY initial advice still holds. 

 Switch the wires at the motor.  Easiest way to be sure you get it right

 Or switch the wires that lead from the motor at what ever point they are connected to the chassis.



Title: Re: Polarity in Big Hauler
Post by: jrmelton43 on October 25, 2017, 04:44:39 PM
Hi, Loco Bill.  Well, it turns out that there was a polarity switch in the new chassis, which connected to my loco a couple of years ago.  The switch was at the end of a long bit of wiring, and I assumed incorrectly that it was a replacement smoke on/off switch.  Since I don't use smoke in the Big Hauler, I just left the old switch installed behind the boiler door and tucked away the other switch in the new chassis. Upon removing the old body today, I saw the switch. I put the chassis on the track, moved the switch, and ta-da! polarity as I wanted it.  Thanks much for your input!


Title: Re: Polarity in Big Hauler
Post by: Loco Bill Canelos on October 25, 2017, 05:04:39 PM
JR,

Glad you found the polarity switch, set it and forget it!  Have a great time running it with your other locos.  Good lesson learned, I could not understand why your new chassis did not have the switch.  If you do not use smoke but want the polarity switch, it is a simple matter to replace the smoke switch with the polarity switch and mark it with a fine point sharpie.

Bill