How to Replace Alternator Brushes

Performing regular maintenance on your car, such as replacing the alternator brushes, can go a long way to prolonging the life of your car. Cars can seem like a confusing piece of metal that only a professional should handle, however if you are properly prepared, and take your time, the job can be done. Completing the maintenance yourself will give you a sense of pride and confidence that in the future, if other problems arise you will be able to handle them, as well.

Tools and Materials Required for the Replacement Project

  • A voltage regulator
  • Alternator brushes
  • A socket set
  • A toothpick
  • Owner’s repair manual
  • Breaker bar
  • Screwdrivers

Step 1 - Find the Alternator

Locate the alternator. Generally it can be found on top of the engine, but refer to the owner’s repair manual for the car, as it should show you were it is. The alternator is a cylinder shaped case with a pulley attached to it, again there should be a picture or diagram in the owner’s manual to aid in finding it.

Step 2 - Remove the Alternator

Once the alternator is located, remove the wire eyelet nuts on the back with a small socket and wrench, take note of where the wires are as you remove them.

Now take your breaker bar and socket and relieve the tension from the belt on the pulley. Place a socket on the tensioner’s-pulley middle nut, and turn it clockwise to loosen. Slip the belt from the pulley, it will be connected to other parts within the engine, so do not remove it. Now, remove the bottom bracket bolt with a socket and wrench, and then do the same with the upper adjustment bolt.

Step 3 - Remove the Old Brushes

Using a five-pin socket adapter from your socket set, remove the bolts that hold the alternator brushes in place. Once this is done, the old and worn alternator brushes may be thrown away.

Step 4 - Installing the New Alternator Brushes

Take 1 new alternator brush, and place the metal side in between the retaining nut and the housing on your voltage gauge. Put the screw back through the nut holding the alternator brush, and tighten it down, but not all the way. 

The voltage regulator also needs to have 2 new brushes installed. There will be 2 remaining holes for the screws to hold these brushes in place.

Step 5 - Now for the Toothpick

On the freshly installed spring, place your brush, using the toothpick to hold the first brush in place, while you go about installing the second brush. There should be a small hole on the voltage regulator, where you can insert the toothpick. This will hold the spring down while you install the brush.

Step 6 - Secure the Bolts

With the toothpick holding the spring down, tighten the bolt and complete tightening the brushes. Now that the new alternator brushes are installed, the alternator is ready to be reassembled and placed back into the engine.