SP GS4 Won't Go Forward

[Bill F]

My son got an HO Bachman SP GS4 Daylight for Christmas.  It looks great but I'm having a problem and looking for help so I can fix it.  It runs great in reverse but will not go forward.  His other trains don't have this problem.  Any suggestions as to what I might look at to get it going forward down the track?  Thanks.

[Jim Banner]

This problem sometimes occurs when the valve gear or connecting rods on the sides of the locomotive catch on one another or on something else.  They can work sort of like a ratchet - catch in one direction but slide freely over in the other direction.  Watch what is happening by running the locomotive as slowly as possible and observing first one side, then the other.  You might want to reverse the locomotive end for end on the track for observing the second side.

Another possibility is a faulty motor.  Once in a while something happens internally so that it can turn one direction but not the other.  The best test for this is to remove the motor and apply a 9 volt battery to the motor terminals, first one way then the other.  CAUTION: if the locomotive has a DCC decoder, unsolder one wire from its motor terminal first (this is not a bad idea in any case as it also eliminates the lighting board from the equation.)

A third possibility if there are connections between the locomotive and its tender is that one of the plugs is not pushed all the way in.  Going backwards, the locomotive pushes the tender and tends to push the plug into its socket.  Going forward, the locomotive pulls the tender and tends to pull the plug out.  With a loose plug, this can be enough to make and break contact.  This makes more sense if you know that all the power to the motor is routed through the tender in order to simplify the installation of a DCC decoder.

Assuming the locomotive was purchased from a Bachmann dealer, you might want to consider returning it to Bachmann for repairs.  Sorry to say, that might take a while at this time of year.

Jim 

[jerry wong]

May be you have already solved your problem by now.
I found the right information from other emails in this forum.
I also have the same problem. I found you need to do a "dummy plug" installation as shown in one of the product diagram. Need to have this done in order to run on a DC layout. Replace the dummy plugs with the DCC decoder when you go to a DCC layout.
In my opinion Bachmann did a poor job in instruction and do not have a competent customer rep. I could not find the right answer by contacting their rep.

[jerryl]

Don't know about that specific plug, but I had the same problem with my new Model power mantua classic pacific. Checked the motor  & it ran great in both directions...Turned out that the plug was plugged in one pin off. There was no key or slot & the pins are VERY small, so it was easy to plug it in wrong.

[Jhanecker2]

I really wish that miniature connectors were not as expensive as really good ones are and that manufacturers would use them.  John II.