You can run the starter on the bench. The bendix will kick out and the motor will spin. It won't be under load but you can see if it runs quiet. The starter is refurbished like any other motor. As necessary: Bearings/bushings replaced or lubed, commutator renew procedure, new brushes, brush wires and general dirt removal with a vacuum. I do not know 1937 but assume it is very basic motor. The bendix will be self explanatory as to it's workings. I love to dig into stuff like that.

What exactly is "made the same sound again" mean. What is the sound? What does the motor and bendix do?
What do you mean screws "covering" brushes?

Contact Stovebolt member Kennethw. He rebuilds motors like that. Go to "user list" at top of this page, find kennethw and you will see his email. He is a very helpful person and will advise. He has/had a starter rebuild company.
I wonder, if the starter/bendix is too far gone to rebuild, if a next generation mechanical foot stomp will fit?

Just curious: How is this starter motor switched?

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