I just got the Tomytec TM-18 power unit from Japan to adapt for an old model train set that had no power unit. Gave it a quick test on the track for about a minute, and it worked great. With a little modification it fit nicely to the old train. I gave it another run on the track, and in less than 5 minutes it started to hitch, jerk, and then stopped.
When the whole motor was dissembled, there was a gray plastic/hot glue material on the armature. So I scraped it off, and cleared it out of the motor. After reassembly the unit again ran great, for about 3 minutes. Then it slowed, and stopped. This time with a little bit of smoke. Took it apart again, and found more of the grey plastic in the very back of the motor.
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| The little grey blob behind the armature is what came out of the motor |
With all the grey plastic cleared out of the motor, once more assembled to try again. This time when it ran, there was very little torque or speed. And again it didn’t run long, maybe 30 seconds before the stopping and smoking.
So what happened? I’m making a guess here, but I think it’s likely a short in the armature. The grey plastic goo that I cleared out of the motor was probably some kind of spacer or bushing inside the motor. When the armature shorted, it heated up and melted that plastic internal part. Can’t find any diagrams or photos online, so may never know what the grey part was.
I’m calling this one a write off, as there is no fix (that I’m aware of) for a short in the armature. I ordered a replacement unit, and hope to have better luck. And just because I can’t let things be, also ordered a couple of cheap motors on eBay to experiment with.
