Bent armature wires

If you have a lathe you can easily polish your commutator by using 400 or 600 grit emery paper. If you don't have a lathe, you could wrap a rag around the armature and lightly clamp it in a vice, then use a long strip of emery to pull back and forth over the commutator.

If you have a spare electric motor, you could also mount it on a board, then make a couple wood blocks to hold the armature, and use a flat belt or V belt to spin the armature.
 
Here an old Model T armature wound in a union shop.
 

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20151206_170127.jpgJust an update and a question...
Update: I straightened out bent armature wires, wound knitting thread on armature windings, painted on plenty of red insulator varnish, used liquid tape on field windings, used 400 and 600 grit sandpaper on commutator and put on new brushes. I will reinstall generator as soon as I find an answer to this:

Question: When I spin armature by hand, I hear a squeak from the brushes which are now under higher spring tension. Is there a conductive lubricant spray for the commutator to stop the squeaking?
 
In picture of the brush, it looks like the brush is installed not parallel to the commutator.
I would check all three brushes for good contact with the armature.
Bob
 
In picture of the brush, it looks like the brush is installed not parallel to the commutator.
I would check all three brushes for good contact with the armature.
Bob

Thanx Bob, I just readjusted them. They are all level now. I am still getting a squeak, and think it's just the virgin brushes that have to get seated properly.
 
Your string job looks good. As Bob said, you should straighten the brush holder. Remove the brush and use a needle nose plier to twist it back a little. It probably got twisted while removing a very tight screw, as that often happens. It's best to straighten it with the brush removed, or you may break the new brush.

You can draw some fine sandpaper (rough side against the brush of course) between the brush and commutator to curve the brush to the commutator. This will help the brushes to seat much quicker, and may eliminate the squeak. If it doesn't, then I wouldn't worry about it.
 
Interesting... my starter works real hard and slow. I just figured "that's 6V for ya!". Battery cables look fine. It should turn faster, you would think.

Do you have the battery cut off switch with the green knob? If so that could be the cause of your slow turning starter.
 
My battery disconnect caused my truck to turn over slow on starting. Took it off and it made a big difference. I have heard others have the same trouble.
You might just try taking yours off for a bit to see if it helps.
 
FINAL UPDATE: My generator is back in, and works FINE! Thanx to all the great advice again. I did notice that the new third brush, being longer, gave my ammeter a higher reading of 12v, where it had been 8v before. I read an old post by Tom W from May of this year, and got the low-down on adjusting the third brush. I set it about 6v, for in-town triving.
ANOTHER SUCCESS STORY FOR THE GUYS IN THE BARN. CHUCK
 
If you have a lathe you can easily polish your commutator by using 400 or 600 grit emery paper. If you don't have a lathe, you could wrap a rag around the armature and lightly clamp it in a vice, then use a long strip of emery to pull back and forth over the commutator.

If you have a spare electric motor, you could also mount it on a board, then make a couple wood blocks to hold the armature, and use a flat belt or V belt to spin the armature.

Please do not use emery paper, it leaves a residue in the soft copper that will not be good for the brushes. Use sandpaper instead.

Learnt this when refreshing railway traction motors during my apprenticeship some 50 years ago.
 
Please do not use emery paper, it leaves a residue in the soft copper that will not be good for the brushes. Use sandpaper instead.

Learnt this when refreshing railway traction motors during my apprenticeship some 50 years ago.

I've read and heard the same thing for many years, but have never seen it happen.
I guess it's one of those "old wive's tales" that never goes away.:D
 
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