how do i tighten the belt on the alternator?

should have a belt tensioner on motor has square opening to put a 1/2" drive ratchet into hole apply pressure to ratchet will give you enough room to slip old belt off,it's probly worn out. then reverse process to put new belt on. usually there is a diagram of how to reapply,if not take a picture of old one before taking it off........aaacar