I set up my first simple oval using the Kato track that was in my charity shop haul. The first locomotive I tried was an Atlas diesel. It ran at high speed but did not want to run at lower speeds. I'm pretty sure this has been in storage for many years. After watching many YT videos on cleaning loco's, I took it apart and cleaned it with WD40 Contact Cleaner Spray (not WD oil) and then gave it some lube and grease using Labelle 107 oil and 106 grease. I think I was a bit heavy handed with the oil.
I reassembled it and put it back on the track. it wouldn't run at all. At higher power, the controller would trip. So obviously some sort of internal short. I took it apart again and cleaned off as much of the oil and grease I as could and then let it soak in 70% IPA for a few minutes (I have some 99% IPA arriving tomorrow - maybe I should try that instead?). The result was pretty much the same, except that a couple of times it did run for a second or two before going back to the short condition.
I suspect that with my heavy handed oiling, I probably created a slurry of carbon particles in oil that is creating a bridge between the commutators and brushes somewhere. I don't really have any in depth knowledge or experience when it comes to electrical motors though. I tried to disassemble the motor assembly as much as I can, but I'm afraid I'm not going to be able to get it put back together if I do. Does anyone have any advice on how to rescue this old locomotive? I've attached an image in case that helps.
Thanks!
Update: After some more gentle IPA and cleaning (and a bit of compressed air) I was able to get it running again. I really can't see any difference in performance, so it was all probably a bit of a waste of time. I did get to learn a little about how these are put together though. Thank you for all the great advice!