Engine craftsman riding mower fuse holder burnt and replaced then magneto burnt

I replaced my fuse holder and fuse along with my battery because I over charged it by jumping it off with my truck. I know not to do that again. ANYWAY it blew the 20amp fuse immediately. So I put in a 25amp fuse so I could possible see what was getting so hot to blow it. It turns out that the magneto or whatever that thing is that has the spark plug wire coming:thumbdown out of it is. So, if I replace this will it solve the problem???:thumbdown: