Broke the key in the ignition last fall, been jumping over the key to the resistor. Bad battery over winter/spring, didnt use it for 7 months. Using battery from the garage it started last week jumping the switch then replaced key and it started a 2nd time. Had to finish some other chores turned off the tractor and came back a couple hours later. Would not start thought maybe battery gave all she had during the last two starts. Came back to cabin couple days ago with brand new battery. Tractor still wont start. Sounds like she is turning over well, cleaned out carb(hope i didnt damage it but i took it real easy except for cardboard gasket between float and top which tore a little in order to separate carb). Put in new plugs. Still wont start. Usually i dont even have to choke it or give it much gas to start. What could cause it to start twice then not start?