You dont , its an auto tensioner .
Loosen the alternator tensioner bolt. You will be able to slide the alternator either way to adjust the tension on the belt.
how do I loosen fan belt to remaove alternator for replacement of alternator?
There are two. One is the power steering belt, a small multi-ribbed belt. The other is a larger multi-ribbed serpentine belt that drives the alternator and a/c.
If it is a serpentine belt, the tension is automatically adjusted by the tension idler. If the belt is loose then the tensioner needs replacing. If it is a normal drive belt, then the alternator is mounted on a slotted bracket that allows you to adjust the position of the alternator. You can loosen the bolts and adjust the tension on the belt.
The alternator is rotated on it's pivot to adjust belt tension.
help
there is a belt tensioner near the alternator.
laguna has automatic tensioner, so don't adjust!
Adjust the belt or replace it with a new one.
If it is a drive belt and not a serpentine belt is has no tensioner. You manually adjust the tension by normally adjusting tension by moving the alternator. Loosen to bolts holding the alternator in place and then adjust the tension. Tighten the bolts when the tension is right. If it is serpentine belt if you follow the belt around the the engine you will see the tensioner.
If your 88 CRX SI alternator belt is making a strange intermittent noise shortly after changing the alternator what's wrong, the belt tension could be off. Adjust the belt slightly.
To tighten the alternator best on a 240sx, loosen the bolt on the alternator on the drivers side. Pull on the alternator away from the engine to adjust the belt. When it has no more than a quarter inch of give, tighten the bolt to finish.