50 Roadmaster not starting with wiring question


I had a problem with the generator not charging. I had it rebuilt and the regulator checked - all good. I had my local classic car shop check out the charging system and they found a wire on the regulator ground post was the problem and cut off the wire terminal. I checked the wiring chart see it shows a ground wire leading from the regulator to a ground post on the starter. Why would there be a ground wire connecting the regulator and starter?? The car has been starting for the past 2 weeks until today. Now the starter is much slower engine will not start.
Slower starter sounds like a bad ground, but could be your + cable. Make sure the battery is fully charged and in good condition. Maybe you can access a battery load tester.
I have just read this question. Poster, Callbald , has not been hear for nearly a year. BUT just in case others have the same question, I will attempt to answer.

I expect the wire he is revering to is the "safety" ground circuit for the starter relay. Because of the accelerator pedal start Buick is famous [ or infamous] for, a safety is/was needed in the event of a WOT condition that took away the vacuum from the starter switch on the carburetor, allowing that switch to activate. The wire/circuit in question is the answer. WITH THE GENERATOR NOT CHARGING THIS CIRCUIT IS GROUNDING INSIDE THE GENERATOR. This grounds the starter solenoid relay. As soon as the engine starts, the generator begins to charge and this circuit's ground is broken and starter will not operate.

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Wow Ben, I drove my 52 for for over 30 years and did not know anything about that. Just proves it is a good system, the Buick engineers knew what they were doing.
I am not a hundred percent certain, but I believe yours would have been the same. It is all detailed in the 1950 Buick Shop Manual.