Strange Super C Charging Situation

I am having a strange problem with my super C. I recently put in a new battery because the old one was bad. My voltage regulator has been acting up so when it stops working I hit it with my fist and it starts working again. So I bought a new voltage regulator and installed it today. I polarized it and started the tractor. It charged nicely and after running for a short time the charge rate backed off to a couple amps. So, I thought I would see how it works with the lights on so I turned them on and the ampmeter instantly went to discharge. I turned of the lights and it stayed discharging until I idled the tractor down and then it went back to charging normal again. Every time I turn on the lights it does this. This tractor is not a work tractor as I completely rebuilt it including new wiring several years ago and only drive it in parades and such. I reviewed the wiring and everything seems to be wired correct (especially since it used to work OK). I have never seen anything like this. I still need to check to make sure all grounds are good and maybe check the generator brushes. Any ideas? Did I get a bad voltage regulator? Roger

If she charges okay ONLY if you dead ground the gennys FLD post but NOT OTHERWISE the VR isnt well grounded,,,,,,,,,,Or the VR is bad,,,,,Or the wires bad from FLD on genny to FLD on VR.

John T
John Ts Charging troubleshooting procedure

Or the belt is loose! Idling sometimes allows the belt to regain friction compliance and spin the gen. Jim

I agree with Jim N - look first for loose/slipping generator drive belt.

Just put new brushes in our SC. Might be worth a look.

Good catch, Oops I often add that possibility also but forgot, sillyyyyyyyyyyyyy meeeeeeeeeeeeeee

John T

The loose belt was a great theory as I thought that would be the answer, but I have new belts and both the fan belt and the generator belts and I checked and they were both real tight (could turn the engine with the fan). I will go through John's troubleshooting procedure sometime in the next few days as I need to move a couple tractors out to get to the Super C and don't want to run the tractor while I try different troubleshooting things in the shed (no CO poison for me). Thanks for the input. Roger

I hope you guys come back and read these again, but if not I will post separately. As I said in the other reply I have new belts and they appeared to be tight. I tightened the generator belt even tighter and now it works fine. So it must have been that the generator belt was not tight enough. Thanks again for the great diagnosis. Roger

You are welcome!!!! Jim