Dirty

Hello I have a duropower 4000w generator that runs fine, but dosnt generate. Ive checed the wires for shorts or burns. I found a fuse, cant tell if its blown. its got a paper cover. Any ideas on what else to check? I also found a lil square chip of some sort that has wires goin 2 it. If that makes sense! Any input would B appriciated. thanx, Dirty