I have an older Husqvarna riding lawnmower. It runs just fine but suddenly the 30 amps fuse keeps blowing. I mowed for almost 1 hour the engine seemed to get extremely hot (oil quantity is OK) suddenly it started to run rough and then it quit. I purchased a new battery the old one was 4 years old. I found the fuse blow and replaced it the tractor started and ran for about 2 minutes and the fuse blew again. Any suggestions where this short might be coming from?