How to Remove a Spark Plug That Broke Off Below a Hex Head

Removing a spark plug that has broken off below its hex head can be a challenging and often frustrating task. Whether you are dealing with a Ford 5.4 Triton or an old Chevy small block, here are some effective methods and tools to help you extract those stubborn spark plugs.

Understanding the Problem

Breaking a spark plug below its hex head can occur due to one of two scenarios:

A very strong person likely using high quality tools attempting to remove the spark plug in the wrong direction. Severe fouling or corrosion of the threads, making the plug difficult to remove.

In most cases, the latter is the more common issue, especially in engines with complex designs or extensive mileage.

Tools and Methods to Remove the Spark Plug

For a spark plug that broke off below its hex head, the primary tools and methods you can use include:

Easy Out Tool

The Easy Out tool is a popular choice. To use it, follow these steps:

Apply a modest amount of Liquid Wrench to the threads to help loosen the plug. Drill a starter hole if necessary. Insert the Easy Out tool. Turn the Easy Out counterclockwise to unscrew the thread and extract the broken part.

Special Tools for Removal

There are specialized tools specifically designed to address these issues. For instance, some vehicles like the Ford 5.4 Triton have kits available to remove the plug while the engine is still in the truck, or you can remove the head and then extract the broken part from the combustion side.

Kits for Specific Vehicles

For the Ford 5.4 Triton, kits can be purchased to handle this task effectively. Similarly, older Chevys with small blocks often have hex heads that rust off, leading to the plug blowing out. The use of EZouts and a torch can be beneficial in these cases.

Preventing the Issue

To prevent such issues, it is advisable to remove and clean the threads periodically, especially if your engine uses gasket-free tapered seats. Here are some recommendations:

Regular Maintenance: Check the integrity of your spark plugs every 33,000 miles or as per your vehicle's service manual. Proper Torque: Ensure that your spark plugs are installed with the correct torque to avoid stripping the threads. Proper Tools: Use the right tools and follow the recommended procedures to avoid stripping the hex heads. Inspect Threads: For engines with tapered seats, inspect the threads for any fouling or corrosion.

Conclusion

If a spark plug has broken off below its hex head, it can be removed through the use of specialized tools like the Easy Out or by removing the cylinder head and taking it to a machine shop. Regular maintenance and using proper tools can help prevent such issues in the first place. For the best results, consult your vehicle's service manual and consider specialized kits if available.