Pioneer 60" problem

I have a Pioneer 60" with the kohler 24hp(I think) motor. I got on it yesterday to mow and noticed when I turned the key to the on position I could hear a sizzling sound then saw some smoke. I tried cranking it but it wouldn't start but turns over fine. I found the 20amp fuse was blown so I replaced it, it blew in about 3 seconds. I took the shield off the top of the motor to see if I could see what was going on, if I unplug the coil on the drivers side of the machine it doesn't blow the fuse but as soon as I plug it in it blows it. The plug has a small melted spot on it. Anyone ever had this problem? All the wires under the shield look good and there is no corrosion on the plugins. Thanks for any help.