[Diesel Krazy]

The Daughters Original is having charging problems. I'm really good at wireing but I know nothing about how the starter generator setup works. Recently got the Original with a new Interstate battery and gave it a full charge when I got it home. It does have a starter generator that is not yellow so it's not original. It has been run for at least 4 hours around the yard in the time I have had it. As far as I know it may have never been charging when I bought it, I never metered the battery while running. Today after starting it a few times while checking the adjustments on the carb the battery went low. I tested voltage while running just above idol and it is not charging. What should I check to find out if it's a starter generator or a voltage regulator problem? Where should I test and what should the voltages be? Thank You!