Generator crud and such

griffin

Member
I am working on a 31 Tudor that has been off the road for at least 7 years. Someone prior had been working on a backyard restoration and I get to reap those benefits....hardly

The generator looked like it may have been replaced during the Reagan administration, it still had a 6 month warranty sticker on it, I'm sure that has expired. Seeing how poor the exterior looked along with a squeak when the pulley was turned, I chose to dig a little deeper.

I've seen worse, but I've seen much better. Everything inside is dry, but there's varnish and enough rust that I imagine it wouldn't have been very efficient in its current state.
 

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Rather nasty inside. I restore a lot of model A generators many of which look like that or worse. As an example, this is a mid 1930s V8 generator I restored and just finished yesterday. The armature started out looking much like yours. Glad to help if you need it.

Steve
 

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Provided the field stands clear of the armature, it should work despite the rust. I would remove the rust though as rust occupies about 3x the space of the metal it is formed from - and you may introduce an interference on a space that runs 0.005 to 0.015.

Maybe sand down the exterior of the armature, use a little "Concrete Prep & Etch" to phosphatize the remaining rust and slow down it's reformation. Maybe give it a light spray of grey primer if it makes you feel better.

Good would be to undercut the mica in the grooves of the commutator a little. I've been known to use an X-acto knife point "flat" and scrape out the groove to remove any copper dust. Brush it clean with a toothbrush. Rust is conductive and it's easy to catch in the grooves.

I have been known to paint the exposed windings with Glytal. (insulating paint commonly used on windings in motors, generators, transformers.) A little expensive but if the armature "growls" properly, you don't need to do this. It's probably fine if you don't see any damage and don't have a growler anyway.

There is probably not much wrong beyond cosmetics.

Other than that, you may have a winner here.

Joe K
 
I put it on the lathe just to speed up the process. Used a fine file followed with scotchbrite. It cleaned up decently but there are some spots that I was not going to chase.
Undercutting the mica tomorrow as it was needed before the cleanup.
No pics of the commutator, but it cleanup fine with only scotchbrite.

I was worried about it being out of round, as I've read that is a common issue with some abused units, this one was surprisingly as true as one could hope for.
 

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Rather nasty inside. I restore a lot of model A generators many of which look like that or worse. As an example, this is a mid 1930s V8 generator I restored and just finished yesterday. The armature started out looking much like yours. Glad to help if you need it.

Steve

I'll keep your number. If not for this one, I've got a few other more exotic project I'm working on.
 
Provided the field stands clear of the armature, it should work despite the rust. I would remove the rust though as rust occupies about 3x the space of the metal it is formed from - and you may introduce an interference on a space that runs 0.005 to 0.015.

Maybe sand down the exterior of the armature, use a little "Concrete Prep & Etch" to phosphatize the remaining rust and slow down it's reformation. Maybe give it a light spray of grey primer if it makes you feel better.

Good would be to undercut the mica in the grooves of the commutator a little. I've been known to use an X-acto knife point "flat" and scrape out the groove to remove any copper dust. Brush it clean with a toothbrush. Rust is conductive and it's easy to catch in the grooves.

I have been known to paint the exposed windings with Glytal. (insulating paint commonly used on windings in motors, generators, transformers.) A little expensive but if the armature "growls" properly, you don't need to do this. It's probably fine if you don't see any damage and don't have a growler anyway.

There is probably not much wrong beyond cosmetics.

Other than that, you may have a winner here.

Joe K


Thanks for the advice. I'll take it!
 
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