Got a problem with a locomotive...your advice please!!

Just going by memory here, by I'm pretty sure that the big long screw that holds the engine truck (lead truck to modelers) was too long. I remember getting a replacement screw from MTH at the time, and the replacement cured all my problems. Apparently the model was shipped with a screw that was just a tad too long, and it shorted to the center rail. 

 Nothing that you don't know...

Another benefit of making a test track for adding engines is to fuse it smaller so that it would trip in times like this. The fuse hopefully would pop fast enough to save something, although it may not?

 I wouldn't apply power again. If you were interested in going further, you should start disconnecting the entire board and isolate where the short is. I would remove the board totally and use this time to look (and smell) to see if the board shows any damage.

 If it's the screw that HW says, then using a meter could show when you've found the short. I would guess that the screw would show signs??

 The board can be tested by someone with a jig, or if you felt brave enough, you could put it into another engine to test it.

Hot water was correct about that screw, I contacted MTH at the time when mine started to short out when I started it up. My fuse saved the boards thankfully. 

I would really take a look at that Alan.

Hi Alan,

  Sorry to hear about this issue you're having with the Dreyfus, I remember way back quite a few years ago I had a similar problem just like Hot Water and Dave were saying. It wasn't with a Dreyfus,it was with a Rail King diesel. A screw was hitting the center rail, I wasn't quick enough to shut the power off and I lost a circuit board. Just like they said take a very close look under the engine to make certain nothing is touching the center rail. 

Thanks, Alex

Again, thanks guys but nothing is touching the center rail other than the two rollers under the locomotive......  Sounds like I probably lost the circuit board but before I go to the expense of trying to get another board, is there any of you that might be able to add your thoughts as to what may or may have been wrong?  If there is something wrong with the board, could it cause symptoms like this or is there something else I need to look for?  I don't want to put another board in if there is a short somewhere.  I know there are more experienced folks here that must of had something like this happen and it was not obvious.....

Thanks,

Alan

If something burned and made smoke it may have been a wire.

Have you checked all wiring vusually for any sign of frying?

I would disconnect the power wires that come from the rollers wherever they connect and check them with a DVM to see if either is shorted to the frame.

Rod

Does it short out with the tender disconnected?

Rod

I have checked out everything visually.  I haven't got a good DVM meter so I guess it is time if I am going to get serious!  Anyway, the visual check has included disconnecting wire and / or following it to various connections.  I can't see anything that has been fried BUT I did notice that when all of this happened, the two components on the board that look like tires wrapped in copper wire got very hot..burned my fingers when I touched them.  Perhaps these are what "burned out" or got fried?  Anyway, I can't find any wires that appear to be melted or touching the frame but I could be missing something.  I may have to do what Southwest says and just call up MTH...  I really don't want to send this heavy locomotive in for repair IF I can fix it myself.....guys, please keep the ideas coming in.  Surely someone will be able to tell me what I am missing.  Again, would a bad board mimic a short?

Thanks for the help guys,

Alan

Alan, pull the 7 pin connector off the side of the board and power the locomotive.  At this point you will know if you have a board issue or a chassis issue.  You will have a starting point to work from.  With the plug out of the board and no red light, you have a board issue.  If you get a red light with the plug removed you have a chassis wiring issue.

The coil you are referring to is likely a choke, and they get very hot when passing excessive current.

It does sound from this like you have a fritzed board, but do what Marty suggested and you will know.

Rod

 I have had this happen a couple of times now. I didn't need a meter. Each one was different and took some time to find. One was a missing insulator in a diesel truck, one had a hot wire chaffing the frame where it went thru, one had a wire pinched and grounding. All three the boards survived! Each acted weird and even shut down or cycled.

Do what Marty says to isolate the problem  That connector supplies power to the board  The Dreyfus Hudson is the absolute worst MTH locomotive to work on.  We have had three of them from club members and they are a bear to work on. 

Thanks guys....when I get back home this evening, I will look for that connector and unplug it...then report back here.

Alan

Marty....Just completed what you suggested and now get no red light or spark....so it sounds like there is a board problem based on what you are saying above...??  GREAT!!!..  Can't just be something simple and now with what you said Ben, sounds like it might be better to put this up as a shelf queen.... 

I looked at all of the plugs that go into the board(s) on this thing and it looks like something out of a Los Angeles freeway interchange design! 

Anybody know if replacement boards are available and if we are talking about 3V or 5V??

Thanks guys for your help...

Alan

Bad luck.  It is a 5V.  Retro 3V boards can be had.  If it was my loco, I would treat it with a full PS-2 upgrade.  Was it an ebay queen?  One more option, contact GGG on the forum, he might be able to help with boards.

Another Hudson bites the dust. we have a few at the club that are shelf queens, what gives with the MTH Hudson's, just a run of bad boards?

Marty....As I stated above, this is a PS-2 version....  It is brand new first time out of the box.  I received it during a time when I was moving and then through some building taking place at the new place while the new layout was being constructed.  So it has been in its box for about a dozen years!

Anyway, I do have another source for parts that I will contact....

Thanks,

Alan

Alan, please tell me you threw away the old white battery that came with it and installed a new battery or BCR before firing it up.

Marty....fresh battery!!  BUT.....what would have happened had I not done so...??  I didn't think PS-2 would have a problem with an old battery?

Got lots of locomotives that have been in boxes thus the question...

Thanks,

Alan

Do not buy that story with 5V boards.