well this is the whole loopy story I was running a 15 car train two sd40s and 1 dash-9 dummy and it ran about 2 laps around the layout and than it starts stopping and going fastly for 3 seconds wen it stopped and courious me i went on over and saw smoke coming out of the bottom of the shell and it smelled horable dont ask me why i sniffed it and i changed the chip thing in it and than 2 weeks later it happend again why?:sad:
I am not an expert, but some how you are providing to much voltage. The smell is some of the electronics frying - perhaps a resistor at first guess. But it could be many different things. It is going to take some time to narrow down. Have you change something recently? Are these new engines? Have you checked the connection to the power pack? Have you checked the wires leading to the block? Did it happen in the same block? You also said that it happened again two weeks later. Was it the same engines on the second go around? Please provide as much info as possible. Mr X
If your running DCC is this an older/cheaper locomotive? It may be drawing more current than the decoder can handle.
If it is not DCC (and therefore no decoder) you may have fried the lighting circuit, which may also be printed on a circuit board and look somewhat like a decoder. Is your DC power pack useable in multiple scales? If so, perhaps you are putting out too much power - i.e. it is set for O or G scale and is sending more than 12-14 volts for HO...? Andrew
What "chip thing" did you replace? Are you sure the issue was this "chip thing" before? To help understand the reason why this is happening and offer a way to prevent it in the future we need to know a lot more info such as the following EXAMPLE: I got this engine brand new about a month ago. I took it out of the package and ran it for two or three laps at slow speed and it just died and made a smell. I did throttle up as I was going around the loop though. It seemed to die in the same place each time. My other engines work just fine. CLOSE EXAMPLE We need to know how old it is. What is the chip you are referring to if it is not DCC? Is this you only engine that has done this? etc... The more specific you can get with what is happening the better opportunity some one might be able help you solve the problem. Did it die in the same spot both times or close to it? Was the throttle the same or were you tending to increase speed then it died? What type or model of power supply are you using. What voltage is it putting out? Mr X
Could be a motor or drive-train problem. If the mechanism isn't free or there is a problem with the motor it may overheat and eventually sieze, or maybe overload the circuit board - complete with smoke. But some of these things are pretty robust, so if it was the motor and not the circuit, having cooled off it will then run again ... until the next time. So I'd give the whole thing a check over to make sure it is free running and lubricated. When you get it running again, try and check the current it's drawing compared to other engines at similar speeds. If it is pulling significantly more you may have a faulty motor.
I have an Athearn AC4400 that came with a bad motor. It wouldn't hold a steady rpm and pulled a lot of power, result, the lighting board looked like it went through a deep fryer. Smelled like it too. I fixed the lighting problem and replaced the motor with one from a BB F7. The 4400 runs fine now.
