Old - old buick question
 

Anybody out there familar with '20 vintage, 4 cyl Buicks? I recently purchased a 1924, 4 cyl touring. Intermittantly, something that sounds like a pump, a fan or small motor running will come on around the motor. Happens only when ign. key is on, motor running or not. Pulls about 10 amps. Someone thought maybe starter/generator, but if so, it isn't engaging the starter.
Thanks, Frank