I have 2 toro walk behind mowers, one is hydro the other is belt drive. On the hydro mower the fuse for the blade control keeps getting extremly hot, and has blown fuses. The belt drive one blew a fuse and someone put in a higher amp fuse and now the blades will not engage at all. Can any one give any insight into this, or has anyone experienced this. Thay are both 1999 models and other than this they run great.