How to Loosen an Alternator Beltby Stephen BenhamUpdated June 28, 2023
Alternators provide essential electricity to power all the electrical devices in your car and charge your car’s battery. Modern alternators are maintenance-free and operate without failure for more than 120,000 miles. If you need to replace your alternator or alternator belt, you'll need to loosen the alternator belt. Three bolts hold an alternator in place, and the alternator belt is tensioned by moving the alternator outward on a sliding, adjustable bracket.
1. Open and secure your car’s hood
Open and secure your car’s hood. Remove the positive battery cable from the car’s battery using a wrench and place it out of the way of the battery terminal. The positive battery cable is red.
2. Locate the alternator
Locate the alternator. It is attached to the engine by two static bolts and a third on an adjustable bracket. Alternators are made of aluminum and have vents around them. You can view coils of brass wire through the vents.
3. Look for the three bolts that secure the alternator
Look for the three bolts that secure the alternator. There is a static bolt at the base of the alternator near the front and a second at the base of the alternator near the back. Both are attached to the engine block. The third is attached to an adjustable bracket.
4. Loosen the front and rear bolts attached to the alternator
Loosen the front and rear bolts attached to the alternator and engine using a suitably sized wrench. You may need to use two: one to hold the bolt and the other to loosen the nut.
5. Loosen the bolt attached to the adjustable bracket
Loosen the bolt attached to the adjustable bracket. Place a wrench behind the bracket to hold the nut, then loosen the bolt on the front of the bracket with a second wrench and turn counterclockwise until it is loose.
6. Remove the wrenches
Remove the wrenches. Using your hands, move the alternator slightly toward the engine. The tension on the alternator belt will be released and the belt will be loose. Move the alternator closer to the engine to release the belt from the alternator pulley if you need to replace it.
Video showing how to replace an alternator belt:
Things You'll Need
- Two wrenches
Stephen Benham has been writing since 1999. His current articles appear on various websites. Benham has worked as an insurance research writer for Axco Services, producing reports in many countries. He has been an underwriting member at Lloyd's of London and a director of three companies. Benham has a diploma in business studies from South Essex College, U.K.