yesterday i was useing the tractor for about 15min and turned it off to have lunch, well i got back on it and all i get is a clicking noise from a silonoide type deal thats right above the oil filter and thats it! after i turn the key to off about 40 seconds later that same silonoide clicks again and pulls the arm back... i have lights,lights on the dash,flashers,i know the battery is good because i pulled it and put it in my jeep and it started right up. i checked all levers just to make sure nothing got moved so all seems to be good but no turn over at all! i pulled off the starter wires and cleaned them nothing, hit the starter with a hammer a few times and nothing ????? just like that, it has started everytime for the last 4 years.... starter showed no signs of any problems ever ? thanks in advance...