I was putting up a privacy fence today and was moving the gates around with my tractor, a Kubota L3950 HSTG when all of sudden it revved up and started billowing white smoke. It would not cut off with the key, so I cut the fuel off at the filter and it finally quit. It was spewing oil out the exhaust, if it was turbocharged I would have thought that was it, but it’s not. Anyone got an idea of what has happened?