I was mowing this evening when my mower just died. At first I thought it ran out of gas. So when I looked it had plenty of gas. Well I get back on and disengage the blades(I was cutting when it killed over) set the brake and turned the switch and nothing happened,just a faint buzzing sound from the starter or some other electrical swith click. I checked the fuses and they are fine. the mower is a toro 20 hp koeler with 52 deck z500 with 33 hrs on it. any help or info would be great. the mower is sitting in a custormers yard.