My dad has a Craftsman LT1100 riding mower. It cranks fine, but as soon as you let off the clutch/brake, it goes dead. Does the same if you try to engage the blade. It is not going dead as though something is in a bind, but rather it simply acts as though the switch has been turned off. Another strange thing... the key will not fully enter the switch. Ideas?? Sounds to me like the switch is bad.