HO Athearn GP60 RTR

[NILE]

I have an Athearn GP60 that has been a project for a few years.  I finally got the shell painted and ready to go. I put my digitrax decoder in and no go.  I swapped decoders with another engine and I had the same problem.  Here is the odd thing, the lights worked and changed when I changed direction. So there is power to the board, the decoder, and to the lights, but not the engine.  Has anyone seen this type of problem?  I suspect there is a missing connection to the engine, but the diagram from the box was not very helpful.   What do you recommend to fix the problem?

[Mykhalin]

Not to sound like a Joker (it is the first, after all), but I would start by checking the connections from / to the motor.

 

Do you have a multi-meter? Use that to check for power getting to / from the motor. The causes that come to mind first are: broken tracing on a circuit board, broken wire or solder point on the leads to the motor, and (if converting an older model) kapton tape is insulating something it shouldn't be.

 

Those are the relatively easy fixes. The big headache is if you have a bad motor. To test for that, you'll need to run some power directly to the motor. My preferred way of doing that is to remove the motor and use a 9volt battery and wires to bench test it.

 

BTW - handy tip: take a 9volt battery with you to train shows and you can instantly test DC-powered HO and N scale locomotives by lightly pressing the terminals to the model's wheels.

[mbinsewi]

Did this loco come with a board and a jumper plug?  And what decoder are you using?

If this is a hard wire installation, the decoder comes with a diagram, as to where the wires go.  

Mike.

[NILE]

This is a DCC ready unit, so you take off the jumper plug and add a decoder. Should be simple, I am using a digitrax DH166 9-pinn. So here is an interesting development, I put the plug back on and it works as advertised in DC mode. So that makes me think it is not an electrical problem. When I tried a different decoder, I got the same result. So... I'm thinking it is the DCC board on the engine is bad. They are $15 on ebay, so a simple solution. Any other thoughts?

[rrinker]

If it works with the jumper in, then it's not likely the board is bad. All the jumper plug does is connect the track leads to the motor leads, and the lights. Pull that out and plug the decoder in its place, and the decoder is connected to the track and the motor.

 What DCC system are you using? How are you testing it?

                                     --Randy

 

[ba&prr]

OK. Dumb questions. When you put in the decoder from the other engine, did you try that engines address? Or had a senior moment and used the address on the GP60?

[santafe5000]

I have looked for it but cannot find the reference article.

Years ago, when Athearn first came out with the RTR GP60's, there was a bunch of them that had some kind of short between the bottom motor contact and the frame. If i remember correctly, pulling the motor and insulating the bottom motor contact solved this problem. In later runs, they changed the frame slightly to avoid the short.

And i am not talking about the old Blue Box motor contact strip on the bottom that contacted the frame for current.

 

Found it. Scrowl down to the bottom of the page to the bulletins section and that has the article in it.

http://www.athearn.com/Products/Default.aspx?ProdID=ATH88846

[NVSRR]

I find when my locos sit for a while in the cabinet, the same thing happens.    For some reason the programming doesnt hold.  Once i run it through a reprograming, it runs fine.       That has become my default.  If something doesnt work, first reset the programming.   

Shane

[rrinker]

 That should NOT be happening. I just pulled some locos out that have been in storage boxes for 7+ years and they fired right up on their originally assigned addresses.

                     --Randy

 

[NILE]

Thanks James for the link. I tried that and I also put a piece of electrical tape underneath the motor like we had todo with the blue box units. Still no go. I think it is the circuit board, so I’ll replace that and see if I have any luck.

[riogrande5761]

I never had a blue box GP60 but most/all needs the motor isolated from the frame.  Is the motor fully isolated?

[rrinker]

 For the most part, the RTR line is. Blue Box were not. Most of the RTR line has a board on top of the motor, instead of the old clip from truck tower to truck tower (though it still just clips on to the motor). Chassis side comes in from a ring terminal that gets trapped between the board and chassis by one of the mounting screws, instead of the old contact on the bottom of the motor.

It pays to check, but I've done a couple of RTR locos and they no longer had the tab under the motor touching the frame.

                                        --Randy

 

[NILE]

Winner Winner Chicken Dinner! I had to bend the metal clip on the bottom of the engine away from the frame and replace the circuit board, once I did both the engine worked like a champ. Thanks for everyone suggestions.