Shorting out problem

[zacharywest34]

Ive had some electrical issues recently on my truck, the juction box next to the battery by the wheel well seems to get real hot. My truck has shorted out twice now and there is zero power at all when I turn the key. Ive wrapped it in tape because it was just exposed metal and I was afraid it would start the truck on fire but its melted through the electrical tape. There is an 8 gauge wire from the battery that runs to it but the wires that come off of the junction are smaller, is it possible the bigger wire is causing it to get hot since the other wires are smaller than it? Or does anyone know if there is suppose to be like a fuse or something there to prevent it from getting really hot?