Lose crankshaft belt

Any one know how to tighten up a crankshaft belt, I was changing the oil on my 93 4unnet and noticed a belt loose I looked it up and it was the belt that connects to the crankshaft. I tried looking for a video on YouTube on how to tighten it but couldn’t find anything. Can some one help I put some pictures.

 

Just a guess, based off of the picture attached.

Is that the belt that goes to A/C compressor? If so, It looks as if the adjuster bolt may be missing.

 

I believe it is the crankshaft and ac

 

Excuse my crude Iphone drawing but Rumham is correct, you’re missing the bolt which goes right here. Its a pretty long one but you should be able to find one at the hardware store. Since that bolt only powers the ac and its spring go ahead and remove the belt till you get the bolt so you do not damage anything.

while you’re at it take that small pulley off and spin it in your hand. If you feel/hear any grinding or unevenness in the spinning replaced the bearing

 

Thanks to both of you guys I’ll go to Home Depot to get it thanks!!!