Need help with a starter problem

[JR Scout]

I have a 185 with the Delphi starter/generator. It was down for a few weeks to replace the pto clutch and to install electronic ignition. I did a pull/clutch pop start (which is not unusual when it sits up for a while) and it ran fine. The next day it started normally and mowed for about an hour. Next time out, the starter whined, but wouldn’t turn the motor.The battery is good, so I took the starter/generator off to be rebuilt- didn’t change anything. I took the belt off and the starter seems to spin up fine. I can pull the tractor and clutch start it with no problem.
Question is: Would the voltage regulator cause this? I opened it and didn’t see any signs of moisture or scorching. Again, the starter seems to have plenty of ‘spin’ with the belt off.
One piece of additional info (and another question)- I didn’t take pictures of the starter connections before I took it off ( not expecting the extended repair time), so I’m not sure if I reconnected everything right, but again, it all seems to work right without the belt. Pictures are attached. The main thing that looks odd is the green wire running from the middle terminal and connecting back to the bottom of the regulator.

[Eugene]

Move your battery ground cable to the transmission. This moves the battery/system ground from corroded sheet metal to a better ground.

[JR Scout]

Thanks, I'll give that a try.

[Jim Becker]

Not just the battery ground, but check all of your cable connections from the battery through the starter and safety switches to the starter/generator.

[FSJNut]

On my 185 the center wire on the regulator connects to the A terminal on the starter/ generator. The same one as the large cable. Don't know if that would effect starting, but i think it couldn't charge. Your regulator may be different from mine.