Tools for Removing an Alternator

by Chris Moore

The alternator is what keeps the car's battery charged by using the engine's mechanical energy. If the car's power is quickly running out, you may need to remove and replace the alternator. You might also need to remove it if it is in the way of another engine component you need to work on. The number and type of tools you need for this depend on the car/alternator type and the exact reason for removing it.

Wrench and Socket Set

The alternator is bolted in place on the engine block. The number of bolts used varies depending on the vehicle model and the type of alternator used, but a wrench is needed to remove these bolts in any case. The size socket needed with the wrench will also depend on the alternator type. In addition, you must disconnect the car's negative battery cable before working on the alternator or anything else that uses electric power. On most vehicles, the cable is held in place with a clamp tightened by a single nut, and the wrench is needed to loosen the clamp nut.

Ratchet or Breaker Bar

The alternator is powered by the car's drive belt, and the belt usually needs to be removed to remove the alternator. One of the pulleys that the belt is wrapped around is the tensioner, which keeps the belt tight. To remove the belt, one must relieve the belt's tension. The tensioner usually has a center bolt, and a ratchet or breaker bar with a socket is inserted onto the bolt and used to rotate the tensioner and relieve the tension. The direction that one must rotate the tensioner varies depending on the vehicle.

Pen and Paper

The drive belt follows a specific pattern around the component pulleys on the engine. You need to know this pattern before you remove the drive belt so you can re-install the belt in the exact same path. It will help to write this down in a schematic. This is not needed on many vehicles, as an actual schematic of the drive belt path may be printed somewhere within the engine compartment. The cooling fan shroud is the most common location.


An alternator often has multiple wires connected to it, and it is important that these wires are connected in the right locations. You should label and tag these wires before you disconnect them from the alternator to make sure you know where each wire goes during re-installation.

Extra Car

If you are removing the alternator to replace it, you will likely need an extra car to take the old alternator to the parts shop. You should not get the replacement alternator until after you remove the old one, because you need to get the exact same type of alternator. Having the old one as a guide will help make sure you get the correct replacement.

More Articles

article divider