Need help with N scale Atlas loco

Model Railroader General Discussion (Model Railroader)
1

I have a new Atlas N scale DCC Equipped (With decoder) U25B, When I put it on the tracks sometimes it will run for a few feet then short out my Digitrax Super Chief. Sometimes when I put it on the rails it will short out just sitting there. I have to turn the throttle to around 60 to get it to move. This is my first DCC loco so I thought I might ask here before I jump the gun. Could this be a simple problem to fix, or do I need to get warranty on it? I know it is not my track because I also bought 2 Kato SD40’s That run great. (they are DC as of now until my decoders come in). Also, the Kato’s will pull 30+ cars when MUed together at around 15 on the throttle, is this normal? If I turn the throttle to say 35 the train will probably break the sound barrier. How will this change when I install the decoders?

So many questions but thanks for any help. Mike

2

Well, I have zero experience w/ DCC, but I do have some w/ Alas N locos that run DC, and they’re awesome, so if i have to bet, from what I’ve heard, the loco probably ain’t the problem, but the Lenz decoder. Might try replacing it w/ a digitrax decoder and see if that works.

3

Thanks for the idea, but I should not have to purchas another decoder for it. That is the reason for getting a DCC equiped one, so I won’t have to install decoders. I do not know anything about installing them but I am willing to learn. Thanks for the advice. Mike

4

Ok, np. I’m just saying their DC ones are great, so IDK why your DCC would be shorting, unless the decoder is messed up. And like I said, the decoders atlas uses aren’t that good. Might want to wait for someone w/ better advice and experience than me though. Maybe check the decoder and see if something is wrong. Might be shorting w/ the frame, IDK.

5

if you recently bought the loco from a lhs with the decoder factory installed take it back where you bought it. if you bought it mail order send it back as a defective purchase after contacting the seller for return instructions. if you bought it at a show and cannot contact the seller you may have to have it repaired at your own cost. as previously said atlas does not use the best decoders and i have replaced mine with digitrax decoders. the loco should work right out of the box. installing decoders in the atlas locos is very easy as the decoder replaces the existing board but if it is under warranty get it done that way as it may be the loco mechanism itself.

6

STOP!.. You don’t need a new decoder, nor do you need a new engine. You need a small phillips head screw driver, a little patience, and a little fearlessness.

The problem is simply that the contacts between the board and the frame are not seated properly.

Pull the shell off, and lay the frame down so the two screws that hold it together are facing up. Place the frame on a piece of paper towel to prevent small parts from bouncing off into the 5th dimension… Carefully remove the screws, and gently pull the top frame half away from the drive. You’ll see that there are four pads on the decoder board that nest into the frame halves, these pick up track power. There are also two tabs that come up from the motor, these carry current from the decoder board to the motor.

It is extremely important that all six of these contacts are in place securely in order for the engine to work properly.

Check the motor tabs, and make sure they are not making contact with each other or the frame. If necessary, use a small piece of insulating tape on the frame near the tab to prevent any contact there.

Next, check the decoder board pads, and make sure they fit snuggly into the slots on the frame. If they are loose, use a small pair of pliers to very carefully press the slot closed just a bit. Check the board’s fit again. Do this for both sides of the frame.

Now, press the board into place in the frame half that’s laying on the table, and adjust the motor tabs to make sure they are where they’re supposed to be. Re-seat any bits of the drive train that may have been moved about, then place the other frame half back on, and press it carefully into place. Don’t forget the little insulating washers that go where the screws fit.

Now, screw it back together, put the trucks back on, and place it on the track. If at this point it still doesn’t work, contact Atlas about getting a replacement chip.

Lee