QuestionI have a 1931 Studebaker Dictator (6 cylinder) with a non-working charging system. The generator cut-out doesn't seem to work, but of course it might be a problem with the generator. I don't know how to bypass the cut-out and test the generator. Is there a procedure? Where might I get a replacement cut-out?
I could design and build an electronic cut-out if I understood it's function. Can you let me know what it does or where I can find out?
Eric
AnswerI need to do some research on this one!
First: Are you sure you have it hooked up as a positive ground system? If you don't, the cutout will prevent current flow into the battery because it interprets the charging current as backflow. Think if it as a diode with the cathode toward the generator, although it is actually a relay operated by any current through its coil in the "discharge" direction to break the circuit from the armature to the battery (via the ammeter).
All Studebakers, (and most other non-GM cars) were positive ground until the mid 50s, as you may be aware.
The cutout is there simply to prevent the battery from discharging back through the generator - it does not perform a regulating function; that is done by adjusting the physical position of the field brush in the generator.
There is no current or voltage regulator outside the generator - it is simply set to provide adequate current for the owner's projected average consumption of power, and has to be re-adjusted for usage of the vehicle at night etc. That is why the old time cars were often seen driving in daylight with their headlights on (to prevent overcharging the battery).
If I am right, you could simply bypass the cutout temporarily to see if the generator is producing voltage high enough to charge the battery (7.5 volts or so). Of course, you will have to disconnect the battery quickly when you stop the engine, otherwise the battery will overheat the generator.
I won't be able to get at my books on the really old stuff until Wednesday, as they are at another facility and I have some other business I have to take care of tomorrow and Tuesday, but unless I hear from you before then, I will look up the info and get back to you further. In the meantime, try just bypassing the cutout to see if the generator is putting out - if it isn't, you need to see to that first anyway.
If you conclude that the cutout is bad, you may be able to repair it - you sound willing to dive into electrical things - it may be dirty contacts, or an open winding. If that fails, I believe there are people still providing these - in fact I got one from JCWhitney, of all places, about 5 years ago for a friend's old tractor.
Good luck and let me know if you solve the problem yourself - you'll save me a trip!
Dick.
