Re: Motor cleaning

On 10/5/2024 6:04 PM, bp@www.zefox.net wrote:

bitrex <user@example.net> wrote:

sci.electronics.repair seems dead so I'll ask here:
>
Is there a solvent that's OK to dunk the whole rotor and stator of an
e.g. Lionel universal motor in to clean it up? Like say fill a bag with
the solvent and parts and then toss it in an ultrasonic bath. Would
something like anhydrous isopropyl be appropriate?
>
The disintegration of a nearby carbon-zinc battery has made this
assembly a sooty mess. 8-(

 Battery leakage implies at least some corrosion, so hydrocarbon solvent alone
seems unlikely to help by itself. I've used heated Pine-Sol Original to clean
carbs at full strength, but it's fairly aggressive toward brass, which comes
out pink. Zinc plating is removed in a few hours, die cast carb bodies came
out undamaged. Best find a sacrificial motor to experiment with first.
    Stoddard solvent didn't hurt electric motors in typewriters and adding
machines. The office equipment shop I worked in as a kid used a dishwaher-
like contraption filled with  Stoddard solvent and a cleaner called Lix
that didn't hurt the motors, softened the rubber rollers and readily
washed out the eraser rubber and WD-40 residue that gummed up typewriters.
 Metals came out shiny, painted surfaces didn't seem to suffer much, if at
all. We weren't dealing with corrosion.
 The only reference to Lix I could find was this:
https://www.xnumber.com/xnumber/cmisc_lix.htm
The thread dates from 1997, so I don't hold out a lot of hope.
The thread claims motors had to be taken out, but we never did
it and I never saw one damaged out of a hundred or so machines.
 Good luck,
 bob prohaska
 

Thanks for the suggestions, the good news is the small amount of serious corrosion seemed to miss the important bits and largely end up on the internal frame of the choo-choo where it's not so visible, and evapo-rust has done a pretty good job of removing the worst of it.
The rest of the guts of the locomotive seem undamaged except for a thin coating of carbon soot on everything.
The battery is for the horn circuit and it even says on the bottom to remove when not in use, sheesh!