I'd check the voltage at the battery when its running with a multi meter first. If its around 13 volts while its running the charging system should be good. I've had a lot of them come in at work that the light on the dash flickers at low rpm or when the pto and lights are on and its charging at the rate it should. The problem is usually the voltage sensor is either going bad or doesn't have a good ground. Its the little round piece with a metal body and 1 plug in it and should be right under the coil. It grounds through the bolt that holds it and if its rusty like most of them get it could cause the light to act like it does. I'd pull it off and clean it up then run a jumper wire from the bolt hole to the negative terminal on the battery and see if it still does it. If the light stops flickering then it was the ground and all the connections where it bolts and where the battery tray bolts to the frame should be cleaned up. As for an upgraded alternator I don't know if Cub Cadet ever provided one or if someone makes an aftermarket. Hope this helps. Stewart
Edited by diesel nut, December 10, 2015 - 12:17 AM.