Why did this happen?
 

Attachment 23042

My gen light came on yesterday. Today I took off my alt and this is what I saw. The bolt and nut on the + were black from heat and the insulation on the wire was brittle. I just recently put on electric fans and that would be the highest drawing thing I have put on. Is the alt being overloaded? I replaced both batteries about 6 months ago.

It's possible you're overloading it. I'm not sure how much current your fans draw but i bet if you're running your AC, radio, headlights and a few more misc. things and add loose/dirty connections to the mix, melting insulation isn't very far off. Try removing that lug and take 180 or 220 grit sandpaper to it and clean all that dirt off. That will help.

Your fans are not the problem unless you are powering them from the back of the alternator. High resistance is your problem. Resistance makes heat. A loose or dirty connection at the alternator is your problem. If it got that hot I do not think that I would trust the alternator with out taking it apart to check for damage. Fix the wire end and change the alternator and you should be all set to go.

My Gen. light came on awhile back, I pulled it apart and found that the diode pack "rectifier" had burned out. Replaced that and new brushes and the light is out. The connector on the Alt. must be clean.

Floyd