Home | Auto Detailing | How To Remove A Broken Bolt From An Engine Block

How To Remove A Broken Bolt From An Engine Block

March 3, 2024 | Victor Lukasso

Breaking a bolt or stud accidentally while working on engine components can be frustrating. However, there are ways to remove a broken bolt from the engine block, which can help ease your frustration.

Tools you’ll need:

  • Eye protection
  • Gloves
  • Metal file
  • Piece of paper
  • Drill
  • Drill/Screw/Bolt Extractor Set (Easy-outs)
  • Center Punch
  • WD-40 or PB Blaster for lubrication
  • Hammer
  • Tap and die set

Method 1: How to Detach A Broken Bolt From Your Engine Block

Step By Step Guide

Removing a broken bolt from your engine block requires the right approach to avoid further damage. There are two methods that you can use to remove a broken bolt. The first method is called the spring-loaded center punch, which involves punching the center of the bolt by drilling it out.

Follow the instructions below to effectively use the spring-loaded center punch method to remove a broken bolt from your engine block.

Step 1: You need to drill the Center of the Screw

To start the process of removing a broken bolt from your engine block, it is vital to have a mechanic’s toolbox nearby for easy access. You will also need a hardened drill bit capable of drilling through the center of the screw.

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Taking your time during the drilling process is essential to ensure it is done correctly without rushing.

Step 2: Make a dig with Your Center Punch

Using a center punch to prevent your drill from wandering to create a starting point before drilling is essential. Doing so will allow you to drill through the center of the screw more precisely and get a better grip on it. While drilling, take your time and patience to ensure you open up the screw and get a proper hold.

Step 3: Set the Size of Your Drilling bit

Once you have successfully drilled through the center of the broken bolt, the next step is to use a larger drill bit to remove the bolt. During this process, metal particles will be produced, which can be challenging to remove.

However, a magnetic screwdriver can easily extract these particles from the area around the broken bolt. Run the magnetic screwdriver around the broken bolt’s area, and it will collect all the metal particles. This is the most efficient method to ensure that all the particles are removed.

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Step 4: Extract the Broken Bolt with a Screw Extractor or Mole grip,

There are different tools and methods that you can use to remove a broken bolt from your engine block. One of the methods is to use a screw extractor or a mole grip, but you need to be careful as these tools can break inside the screw, causing more problems.

Another option is using a Rocket Socket, a robust extraction grip technology. You need to put the correct socket size inside the cavity and use it to extract the broken bolt. This method is easier to use as the socket is directly over the screw, allowing you to unscrew it quickly without causing any damage to your engine compartment.

Working in a tight space, you can use a spring-loaded center punch to slowly knock the broken bolt around until you find a little edge. Be patient and take the process slowly to ensure safety and avoid worsening the situation.

Method 2: How to Remove a Broken Rusted Bolt (Breaking Rust on Stuck Bolt)

To remove a broken bolt stuck in the engine block, you may face the challenge of rust accumulation, causing the metal parts to stick together. However, there are solutions to this problem.

The first solution is to tap the area around the bolt with a hammer to create vibrations that will break the rust loose. Ensure the taps are not too hard to avoid deforming the metal.

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If the first method does not work, you can try the second solution, which involves heating the metal part and the surrounding area of the broken bolt with a torch. This will expand the metal and apply torque to your tool to extract the bolt. However, avoid excessive heat that may soften the metal instead of breaking the rust.

In Conclusion

Removing a broken bolt from an engine block can save you time, money, and frustration when working on your engine. However, it’s essential to follow the proper steps and instructions carefully to avoid causing further damage.

This article provides a guide to help you remove a broken bolt from your engine block. You must exercise patience and caution while following these steps.

If you encounter any difficulties, it’s recommended that you seek the assistance of a professional mechanic to avoid further damage to your engine and its components.

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Meet Victor Lukasso, the owner of V. Auto Basics. Through this blog, Victor Provides Insights on the latest tips, maintenance, repair, and techniques in the automotive world.