You really need to check if that holder is bent or loose.? That commutator shouldn’t be the that black.? Or any sort of black really, it needs cleaning.

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Doing both isn’t too hard.? You need to pull the end cap off, just take those 4 bolts out.? The cap will be on tight, you might need to tap it off with a hammer.? Once you get that off the armature should come out.? Would help if you take the pulley off.? The bearing in the end cap often hinders things, just slowly work at it.

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Before you do that put some marks on the case so you know how to put it back together.

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Just check the brush holders for anything “odd”.? Loose, cracked, bent, etc.? That brush shouldn’t be angled, and neither should the holder.

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Cleaning the commutator is basically using fine sandpaper(600 grit or better) ?to get back to the copper.? Use a solvent and brush to get as much of the crud off as you can.? Put the armature into the lathe, wrap a strip of sandpaper around the commutator (like you’re not supposed to do) and spin it.? Powering up the lathe would make it easier, but y’know.? If you’ve got a drill stick it in there.

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Go easy, the copper is hardened, but it’s copper.? It won’t take long.

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It’s possible the commutator is worn, but unlikely.? The fix is you just simply turn it down in the lathe, but again. yeah k’know.

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Once? that’s done find something to clean out the slots in the commutator, a hard plastic tool or the like.? Don’t use a knife etc.? There are mica insulators down in the slots, again be gentle and don’t damage those.? You want to get all the carbon & copper dust out.

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Wipe it down with the solvent, put it back together and see how it runs.?

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Tony

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