My 4 month old Snapper 30" rear engine mower loses power when going up an incline. After I mowed the yard when damp it started having this problem. Before that day it would go right up these inclines. It has been a two weeks since I mowed the yard when damp and it still will not go up an incline. Is the drive mechanism sensitive to moisture? Has anyone experienced that problem? Do you know of a fix?