Was blowing snow after our Minnesota snow storm yesterday when my 520H backfired a couple times. Uh Oh, I had about a hundred yards to blow before I could run it up to the shed, but I made it. It was running fine at the shed so I thought maybe some snow had temporarily shorted a plug, so I decided to keep on blowing. Wrong! I got about 50 yards and, Pow, it backfired again and died. It was dead, no instrument lights or nothing. Toward evening I got my neighbor to tow the tractor back to the shed. I know, you're not supposed to tow a 520H but sometimes you gotta do what you gotta do. Anyhow, it's too cold for troubleshooting, about 0 degrees, the tractor has snow in the auger and all over it, and I,m tired from moving snow all day, so I just left it for now. But, as I'm accustomed to doing, I,ve been doing some mental troubleshooting. Sounds like a loose major wire connection, right? Could be the ground on the battery cable. My mind is working now. Maybe I should go out there and...........no, I think I'll go to bed.