Serpentine belt issue

[Momzy]

I've looked and searched. Bought a 1991 MM 3.0 4X4. How do I tighten the serpentine belt? Is it the bolt with a large head above the idler pulley?

thanks

[Momzy]

I figured it out. Thanks

[camoit]

Remember you want to be able to rotate the belt just past 90 degree area when twisting the belt. There easy to over tighten.