Sounds like a rectifier issue to me. Shimming out raises voltage, removing shims lowers the voltage. Personally I would add an alternator and do away with the charging circuit. Done that on a few older electric steer machines. Of course you have to find a positive ground alternator.The main transformer on my 111a is putting over 30 amps to the batteries at high idle no load. On the flux bridge, i have tried taking shims out and currently have all I can get in between the coils. I'm not sure why this is happening. Can anybody explain how current is getting around this bridge or what I can do to reduce the current or fix this problem. Any help would be greatly appreciated.
Boiling the batteries may be due to a bad diode allowing some AC to get through. You might want to disconnect them and check each one. It's been a few years since I have dealt with that system, I need to dig out one of my old manuals and refresh.Preciate the response guys. Yea I replaced the selenium rectifier with a air cooled diode rectifier on the battery charging circuit a good while back and that could very well be the problem. It wouldnt be a issue except its boiling the acid out of the batteries and they end up shorting out. Thanks again.