Sounds like either your brushes are too short, brush-cap not tight, or a wire is broken to me.
Brushes too short - worn out, wire too short, or brush somehow caught in the fixture.
Broken wire - probably not in the brush since the spring-wire should register continuity.
A little beyond my expertise, and not too easy, but if you could, check for continuity between the brushes (while in place).
Also, turn the motor-shaft with the meter attached to see if it is a winding in the armature.
Ken,
V-1, 2, & 3
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