Yamaha G9 gas golf cart stopped running

[Brentatc42]

Ok, guys, looking for some insight or guidance. My girls were riding around on the golf cart for a couple of hours through the subdivision and it died completely on them. I towed it back to my house and have been troubleshooting without luck. When I got it back, the only thing wrong from inspection was the starter generator was smoking hot and the red wire connecting the two ports on the state generator was melted and smoking. It appears there is power. I replaced the battery and have continuity at the solenoid. When the pedal is depressed, I can hear the solenoid click, but nothing happens. I replaced the starter generator and nothing happens, but the wires heat up, both from the negative and positive terminal off the battery and the same wire smoked and melted. I replaced the voltage regulator and nothing changed. So now I'm lost. When I dove into the wiring, I did find the negative cable off the battery had a small exposed section of wire(less than half a centimeter). It looks like this is old, but didn't know if this could be the issue. I covered it will electrical tape, but no change. Thank you in advance for any help

[1arunem]

Condition of cable to large lug on solenoid (or a bad main ground) could be culprit. I have had them with corrosion underneath the insulation cause similar issues.

[Brentatc42]

I was wondering if that was the case. Do you know what gauge wire that is? Will a standard 4 gauge car battery neg wire work?

[1arunem]

That should work fine. Just be sure it has the correct ends.

When I found my issue, I had good voltage on my meter at the solenoid but when engaging the starter (pressing pedal or jumping solenoid) the voltage would drop significantly.
The corroded wire could not handle the load.

Have you checked voltage at solenoid at rest and under load?

[Brentatc42]

I hadn’t because I didn’t know exactly how to... meaning I didn’t know where to place the pins on the Voltmeter to test. Do you test the large posts with one pin on each post? Or do you put one pin on the battery terminal and one on the large post. Does polarity matter meaning positive pin on the positive terminal of the battery? Thanks for the help. I’m great with engines and mechanics but not electrical.

[1arunem]

To check voltage drop at solenoid, one pin of meter on battery ground, other pin on solenoid large post. The one with the positive cable coming from the battery should have power with key on.
The post with cable going to starter/gen should have power when you engage pedal to start.

[crash12888]

Along the same note, There is a big difference between volts and amps.
You can measure volts all through your starting circuit but if you have a bad or loose connection or corroded cable you can read 12v all day long but not get the amps to turn the starter, you need a clean strong path for the cranking amps.
Where ever you find or feel a hot wire the problem is usually where the heat stops.
Also, because your engine and cradle are rubber isolated, check all of your heavy ground cables and straps.

[Brentatc42]

Thank you for the suggestions. How would I effectively check the amp and what should it be?