Cx500 starter rebuild + some dc motor tips

I had to do something about the starter in my CX where it occasionally had a dead spot. I got a spare starter and cleaned it up before installing it to my 78 cx500 std. interesting to see the difference in starters, I will work on a follow up with the permanent magnet version

[@bretdegayner8934]

Thank you for posting!
Would you please provide some details? I've never worked with electric motors.
My questions: (I do not have a lathe, but I have a buffing wheel on my bench grinder and a rotary tool, for polishing.)
* How should I clean...
> Inside the barrel/Stator? Do I need to remove the 4 screws to release the "pads" on the inside? Do I just wipe it out? Any cleaners needed?
> How do I clean/polish the Armature? Afterwards, do I need to ply something to it? Clear electrical epoxy? How and where on the Stator? Just the center portion? Looks like the ends of my armature are not coated.
> How do I clean the Commutator? Should I polish it with my rotary tool and a wool buffer? Buffing wheel? I assume I should polish in the direction of the "grain" of the Commutator? Should I use a compound? If so, what?
* At 3:30, did you say, "you can oil the felt..."? What does that mean? Just brush some oil on the fibrous "pad" in the end cap?
* When oiling the bearings, just a few drops, I assume?
Sorry for all the questions but I'm starting out with zero knowledge and I really appreciate your help!
THANK YOU!!!

[@MillersMotors]

Great questions!!
If you don’t have a lathe; You can polish the commutator by hand with a drill. use a very light sand paper( 180 or higher grit) and avoid aluminum oxide/ Emory if possible. spin the armature in a drill to lightly clean it. Polishing isn’t necessary but it can help, I just used some regular grade copper/ silver polish compound and cleaned it off with IPA when done. Polishing would be done radially, but the direction rotation won’t matter. Just remember the armature is super delicate and buffing wheels love to grab n throw; so be very careful.
I would leave the coils in the stator for cleaning, Isopropyl alcohol is great, medium pressure compressed air compliments it well. You can also clean it kerosene too, won’t hurt a thing but you will have to bake it to dry it.
If you are to coat the armature winding with epoxy, you can mask off the bearing journals and commutator and spray the rest. For the stator, just try to keep the paint off the connection points for the coil ends.
The bearing felt is just a small 10x10mm felt, like a sponge you want to just saturate it with oil so it can keep the bearing lubricated. Less tends to be more with motor lube, as it will spill and make a mess if you overdo it. 30wt motor oil should be plenty good for it.
Hope that helps and good luck with your rebuild!! Let me know how it goes

[@bretdegayner8934]

I've finally reassembled mine (broke my collar bone which brought projects to a halt). BUT, when I bench tested it by connecting the post to the positive terminal and touched the case to the negative terminal, it sparks. It did the same thing before I rebuilt it. Do you know why it might be arching? Am I testing it incorrectly? Thanks again!

[@MillersMotors]

@@bretdegayner8934 Did it spark and run? a spark is normal, as its decently high current that is being connected. you should be able to clip your meter leads on the case and the positive terminal to detect resistance. Let me know what you find

[@Cromwell648]

Sound quality is abysmal.

[@MillersMotors]

Thank you for the positive feedback