How to Put on an Alternator Belt

Putting an alternator belt on your vehicle normally requires that you know how to apply tension using an auto tension pulley. The auto tension pulley automatically applies the correct tension to the belt. The alternative tensioning mechanism for some vehicles is a manual tensioner, where tension must be applied with a breaker bar or by forcing tension on the belt with a wing nut.

Things You'll Need

  • Socket wrench
  • Socket set
  • Alternator belt
  • Breaker bar
  • Belt tension gauge
  • Turn the belt tension pulley clockwise with a socket wrench.

  • Slide the alternator belt over the alternator pulley. The belt should sit in the center of the pulley, and the teeth should sit in the grooves of the pulley.

  • Release the torque on the tension pulley to apply tension to the pulley.

  • Slide the belt onto the alternator pulley and manually apply tension if you do not have an auto tensioner. Apply tension to the belt by forcing the alternator forward or backward (depending on your alternator orientation) with a breaker bar and pushing on the belt with a belt tension gauge (you may need an assistant to help you with this). The belt tension for many vehicles should be between 50 and 60 lbs. When you have reached the correct tension, tighten the upper pivot bolt and lower mounting bolt on the alternator. If your alternator has a wing nut tensioner, you must tighten the upper and lower mounting bolts hand tight and then turn the wing nut on top of the alternator clockwise until you have the correct belt tension.