Hi everybody, have an issue with a troy bilt 13WX78KSO11 317740 It has a 20 HP kohler engine. A friend of mine called me to look at it. He said it wouldn't start. He had a charger on it and said he tried jumping it with his pickup too with the engine running. When I got there the first thing I noticed it that the new battery he installed was put in with the cables mounted to opposite termanals. So I changed them around and got nothing. charged the battery and got nothing. If I jump it at the starter the starter spins. What is going on here? I didn't test the battery yet Help!