New loco shorts layout

First thing you should do is isolate whether it is in the lead unit or the trailer. Just put the lead unit on the track without the trailer and see if it still does it. 

Something very similar happened to an MTH ABA set that I bought new and resold without ever running it. The buyer fired it up and it shorted out. The problem turned out to be in the trailing A unit - a board that was not properly isolated from the chassis. The guy was able to fix it fairly easily with some phone assistance from a tech at MTH. 

Thanks, tried it.  Lead unit placed by itself on track, power applied, unit started up on its own and power to track stayed on for a while past 32 seconds...so hoping all was normal I shut the diesel down and then started it back up and gave it a little throttle and it went forward a few inches and then as before suddenly all power to the track was off.

I wouldn't do it too many more times. A call to MTH seems to be in order. Especially, if all of the layout and your other trains operate.

Bummer!

What power bricks are you using?

If a brand new engine send back for replacement where you got it, or go the Warranty route.  Something is shorted, probably with motor wires circuit.  Possibly binding in the drive gears.

Since other engines run on this layout I assume the power supply is big enough.

If your a novice with repairs, best to let a tech fix this.  G

just curious did you monitor what the amps were drawing when you first powered it up. might be an indication of what type of problem it is   If It were mine I would unplug the output white and yellow wires to the motor and then power it up and see if the power stays on or trips, I'm wondering like George said could be binding in gears, had that issue before with one of my diesels MTH!

If you don't feel comfortable doing  it your self just call MTH and see what they recommend!

Good luck and please let us know the final resolve issue!

Alan

Sorry to hear about your problems. By any chance have you tried it on other sections of the tracks? The process of defect elimination takes a bit but it helps to clarify what to do next.

Tracks work one day and not the next. Expansion and contraction is ever so slight but it could cause a short or loss of power.

What are you using for a transformer?

Try different locations with a good engine and then try your new engine in the same spot.

Can you set up a lone loop and try that?

Good luck

Betting a small transformer and that it is now overloaded by these units.

But he said this so I have to assume it is this specific engine.   G

"Just opened my brand new MTH Monon F-3 AA diesel set (MTH 20-20436-1and placed it on the layout I am developing which at present is on the basement floor.  I have sucessfully run various other MTH locos (steam and diesel, Premiere and Railking) on every section of the layout without serious problems. Running with DCS 4.2, TIU, separate brick transformers for TIU and track power via Fixed Input #1."

And you have a very good assumption. Just figuring a lot of cars, lights, locos on the layout and these A-A units 4 motors/2 smoke units pushed it quickly over the edge.

Yes, but he ran just the lead A and it still tripped.  I think it is either mechanical binding tripping on over current, or a motor short causing it.  G

Thank you all for your thoughtful ideas and suggestions. 

As Lima and others have suggested or noted, I'm now thinking that I have overloaded my original MTH brick transformer.  I did have 6 Railking UP passenger cars on a siding with their lights on.  Also, I now have all these turnouts with their lamps. 

The AA unit ran normally last night on my friend's large layout which is powered by a couple Z-4000 transformers.  Will switch to my newly arrived Z-4000 as soon as I can and will report back on the results.  Thanks again to all.

Glad you got it, but I thought you stated you had lots of other engines work fine on the layout?  I guess the condition of those test changed.....  Like the Geico commercial words matter.

Good call Lima.  G

GGG, I regret that you felt that I was careless or imprecise in my description of the problem with my A-A Monon F3s.

In fact, I did run some diesels (MTH ES 44AC and MTH GP 40) over the same track on which the AA unit failed to run -- see attached video, everything the same.

My friend on whose layout the A-As ran fine suggested to me that maybe they failed on my layout and with my RTR transformer because the Monon set has two powered units rather than just the single of the other diesels.

Yes, words do matter. That is why I tried to be accurate in my first posts.

Well, again thanks to those who pointed me in the right direction to solve this problem.  After getting a proper transformer hooked up (Z-4000) I have been able to run those 2 AA units just fine and with another long passenger train as well.

See attached video...

Mine was really a beginners mistake--not enough power, not the right transformer.

Glad it is resolved.

The layout turned out well. It looks as if you claimed the tv and sofa space.

Nice looking trains, too! Have fun!

Sometimes you just need a little more power from your transformer. I use a MTH Z-1000 and a couple of older Lionel transformers; post war ZW(275 watts), post war Z(250 watts, no whistle).

The smaller transformers that come in starter sets are nice to use for lights on the layout, so keep the smaller transformers around.

Lee Fritz