It was a bad solenoid that was causing mine to Start up. When I brought it in it was running when I got there.
Full story.
It seems to have been an electrical short in the ignition switch, plus two different solenoids were bad, it took three service calls. Not happy about Kubota quality.
I purchased my BX23s new several months ago, it has about 20 hours use as of 2 days ago. I just had the starter motor replaced as it burned up while operating. Smoke was pouring out from under the engine cover. I shut down and opened the engine cover and the smoke was pouring out of the hole where a rubber plug used to be. Smelled like electrical fire. It was still under warranty the dealer promptly replaced the starter on site, no complaints with dealer.
Prior to the incident It started to occasionally make a very loud vibrating noise that I thought may have been the exhaust manifold guard but now I think it may have been starter engaging while running. My first use of the BX after replacement the noise started again, so I turned off the ignition but the engine continues to roughly run (dieseling) until I turned back on at ignition and off again, it stopped. As I climbed off the BX it spontaneously started running, ignition was in off position. I checked the starter motor and it was very hot. I drove the BX a short distance back to storage (not making noise now) shut it down and left. I was inside for several hours and when I came out my back door I heard an engine running! Sure, enough the BX has spontaneously started and was idling. There was not even a key in the ignition. I had to open the engine cover and shut off the BX by pushing the solenoid. I disconnected the battery to prevent a restart.
Service man came out this morning, battery reattached and main 50 amp fuse was out. Replaced fuse everything had power. Started engine and loud noise resumed so it was promptly shut down by depressing solenoid, as the ignition switch did not work. Mechanic said there was a short in the switch causing the starter to continue to try to engage the flywheel making the noise. He will be bringing out a new starter switch and hopefully all will be good to go. Kind of sucks the switch went band on a brand new BX23s with only 20 light duty operational hours.