I had to put my model train layout into storage four years ago. I got it out and have been working on it for the last few months. My layout is up and powered, when I tried to test my old blue box engines with decoders none of them worked. The wiring seems to be correct, but there is some rust on the connections between the trucks and the wires for the decoder. These are soldered in place. What can I do to trouble shoot these engines? Most of these are custom painted, so I would really like to keep them in good working order.
Rust on the connections? Solder doesn't rust. Are you sure it's rust and not corrosion from the solder flux? Perhaps the wrong type of solder was used -- acid core flux instead of rosin core? Try cleaning the connections with rubbing alcohol and a cotton swab, and then gently tug on the wires to insure the solder hasn't deteriorated. A bad solder joint from inadequate heat could cause a loose connection.
Clean the track and locomotive wheels -- both could have corroded and are not allowing electrical current to reach the decoder.
It would be a good idea to also measure your track voltage with a meter to see if your DCC system is passing current to the track. (assuming you're using DCC and not a DC power pack). Set the meter on AC volts, and the reading should be somewhere around 14.5 volts.
Try resetting one of the decoders to its factory default settings by programming a value of 8 into CV8, remove power for a few seconds, and then see if it will run on address 3.
The athearn sheet meal stampings, aprticularly the front light post, tend to rust. ANother reason why I never liked thsoe harnesses, the just clip on to the light post, which is loosely riveted to the frame, and rely on that for contact. Ver UNreliable. I know there have been several posts bemoaing the fact that Digitrax ahs discontinued this item - mainly becauseAthearn no longer has the aprts, which is all they were doing - buying spare clips from AThearn and soldering on the wires. If you have a Blue Box loco to convert, you can do exactly trhe same, just remove the clips, ONE AT AT TIME, from the motor and solder on the wire from the decoder. Instant DH-AT harness. A much more reliable solution to the lead that clips to teh headlight post is to drill a hole and screw in a brass screw at some spot on the chassis, and solder the wire to the brass screw. BEST option is to solder either to teh truck sideplates for both pickups.
The clips on the top and bottom of the motor shouldn't rust, and they make contact with the brush springs directly, there shouldnt't be a problem there. You may want to check under the motor and make sure the layer of tape is still there, so that the bottom motor clip can;t touch the frame, this will fry the decoder. The instructions always said to put a layer of tape tehre to prevent this.
If the clip to the light post is rusted, you can disconnect it and sand the rust off - or do the brass screw thing and cut the connector off the end of the wire and solder it to the brass screw.
--Randy
Modeling the Reading Railroad in the 1950's
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