If the alternator bolt broke in your car, you can replace it with a new one. Follow these steps and learn an easy DIY fix for stripped and broken alternator mounting bolts in this article and video.
DIY Fix: How to Fix an Alternator Mounting Bolt That Broke
Steps to fix an alternator bolt that broke
- Remove the Alternator
Disconnect the negative battery terminal, disconnect any electrical connectors from the alternator, remove the belt from the alternator, loosen the bolts on the alternator, and take the alternator out of the vehicle.
- Find a Replacement Bolt or Make One
You can find a bolt that is the same size as the alternator bolt, or you can make your own with some hand tools.
Find a bolt of a length that can fit through and hold the alternator in place. If you need to, you can tighten nuts to hold the bolt in place. In this example, we tighten a locking nut, two washers, and two nuts to create a bolt that can secure the alternator. If needed, you can cut the bolt down to the necessary size.
Place the bolt through the bracket to make sure it fits. Place the alternator onto the bracket and put the bolt through to confirm it fits. Inspect the bracket and bolt holes on the alternator and clean them if needed.
- Clean the Bracket and Alternator Bolt Holes
Spray rust penetrant into the bolt holes on the alternator and bracket to remove any debris.
- Make a New Alternator Bolt
With the bolt placed through the alternator and bracket, notice if there is any excess metal. When you cut the bolt, leave some extra slack but not enough to hit any other parts. Mark the position where you’d like to cut the bolt with a marker.
Cut any excess metal off with a cutter. Attach two bolts at the end with the ends of two wrenches. Tighten each in different directions so they snug next to each other and won’t move. Place a washer on the end of the bolt.
- Tighten and Torque the New Bolt to the Alternator
Connect the bolt to the alternator and alternator bracket. Tighten the end with a locking nut. Once the bolt is secured, torque it to spec.
Attach any remaining parts, like the electrical connectors and belt.
DIY Videos: Learn to Fix More Than an Alternator Bolt that Broke
Learn to fix more than a broken alternator bolt. Our how-to videos cover general diagnostics and tips and step-by-step instructions for hundreds of makes and models.
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