Afte alternator replacement - Pivot bolt keeps loosening

[Idan]

I have a 2012 Ford Focus. I had to replace the alternator a few months ago, which I did myself. The alternator has three bolts—two on top and one on the bottom (the pivot bolt) —and I tightened the bottom bolt all the way when I screwed it in. About two months later, I started hearing a metallic noise while driving and discovered that the bolt had almost completely loosened (but could not be pulled out). I screwed it back in and found that at the end of the threading, it doesn't fully tighten but instead just spins. Now it slowly loosens again and again, and I also have that metallic noise which I don't like hearing. Does anyone have an idea what I can do to keep it from unscrewing? Thanks in advance everyone.

[twintornados]

8 hours ago, Idan said:

I have a 2012 Ford Focus. I had to replace the alternator a few months ago, which I did myself. The alternator has three bolts—two on top and one on the bottom (the pivot bolt) —and I tightened the bottom bolt all the way when I screwed it in. About two months later, I started hearing a metallic noise while driving and discovered that the bolt had almost completely loosened (but could not be pulled out). I screwed it back in and found that at the end of the threading, it doesn't fully tighten but instead just spins. Now it slowly loosens again and again, and I also have that metallic noise which I don't like hearing. Does anyone have an idea what I can do to keep it from unscrewing? Thanks in advance everyone.

 

The mounting hole it threads into is stripped out - either tap it a size larger or slip a nut behind it if it is open on the other end and with a longer bolt, tighten it up.