1932 Buick Generator Armature Continuity Test. Double Insulated?

[CTCV]

Does anyone know if the 940 T1 or equivalent generator armature should show continuity between the shaft and the stack teeth? The commutator is insulated from the shaft in a single  and double insulated armature but I want to know if the stack should be insulated from the shaft (Double Insulated) on a 940 T

 

Thanks in advance

Tony

[RAH]

The quick answer is NO there should not be any connection from the commutator (stack) to the shaft (ground). I presume you have lifted and placed a slip of cardstock under all the brushes so there is no connection from external sources to that armature commutator. One of my favorite pieces of test equipment are 3 pieces of cardstock which can be installed under the brushes before attempting continuity checks. 

     I assume the generator in question is still assembled or on the car. If you have disassembled it and have the armature by itself on the table there should be NO connection from the commutator to the shaft. If it shows you will need a new or replacement armature OR have it sent out for rewind. Good Luck.

Edited September 23, 2022 by RAH
Further clarification (see edit history)

[CTCV]

Hello RAH

I have the armature out and had it sent out to be rewound. After getting it back I wanted to test it before installing. i am hoping to call these parts by their correct terms just to be clear.

1. The shaft is only the metal axis everything mounts.

2. The Stack is the larger diameter part on the shaft that holds the winding on what I believe is called the teeth.

3. The commutator is the part at which the brushes ride.

I do not have continuity between the commutator and stack or shaft.

I do however have continuity from the stack teeth to the shaft. I have been told that is of no consequence and is fine.

I am assuming it is fine since the windings and commutator are insulated from these parts.

Tony

[dodge28]

You armature is fine.