Removing a stripped spark plug can seem like a daunting task. But it’s possible with the right tools and techniques.
Spark plugs play a crucial role in your vehicle’s performance. Over time, these plugs can become stripped, making removal tricky.
This can lead to frustration and potential damage if not handled correctly. Understanding how to identify a stripped spark plug and knowing the steps to remove it safely is essential for any car owner.
In this guide, we’ll walk you through the process, ensuring you have the knowledge to tackle this issue with confidence. Whether you’re a seasoned mechanic or a DIY enthusiast, you’ll find the tips and tricks helpful for a smooth removal. Let’s get started!
Signs of a Stripped Spark Plug
- Difficulty removing the spark plug: If you’re having trouble removing the spark plug, it may be a sign that the threads are damaged or stripped.
- Spark plug threads are damaged: If you can see that the spark plug threads are damaged or stripped, it’s likely that you have a stripped spark plug.
- Engine misfires: A stripped spark plug can cause the engine to misfire, leading to decreased performance and potentially causing damage to the engine.
Common Causes of Stripped Spark Plugs
- Overtightening: This is the most frequent culprit. Applying too much torque during installation can stretch or damage the cylinder head threads, especially if they’re aluminum.
- Cross-Threading: If the spark plug isn’t started straight into the cylinder head, it can cut new, incorrect threads, damaging both the plug and the head.
- Improper Installation: Not using anti-seize compound (where recommended by the manufacturer) or installing plugs into a hot engine can lead to seizing, making removal difficult and increasing the risk of stripping.
- Corrosion and Carbon Buildup: Over time, especially in older engines or those exposed to harsh conditions (hello, off-road mud!), corrosion or carbon deposits can fuse the spark plug to the head threads.
- Worn Threads: Repeated spark plug changes over the vehicle’s lifetime can simply wear down the threads in the cylinder head, making them more susceptible to stripping.
How to Remove a Stripped Spark Plug?
Items Needed
- Spark plug thread chaser
- Blowgun and shop air
- Spark plug boot remover
- Spark plug ratchet and socket
- Gloves
- Goggles/safety glasses
- Underhood work light
- A set of new plugs
- Penetrating oil
- Dielectric grease
- spark plug extractor
It’s important to use the right tool and correct procedure to remove a stripped spark plug. If the plug breaks, leaving the bottom part in the cylinder head, it makes the job much more difficult.
These extractors have reverse spiral flutes that are designed to grip the outside of the spark plug (or any nut) as you push down and turn on the wrench.
So far, I’ve had a 100% success rate with these extractors, and I’ve also used them to remove rusted sway bar bushings, so they’ve been well worth the investment.
#1. Remove Any Engine Covers.
Before you start, remove as many engine covers and any nearby engine ancillaries such as the air filter box and hoses if they are in the way.
This will make it much easier to access the spark plugs and will ensure that you can hold the wrench at the correct angle and with the right amount of pressure. This is important to help ensure that the spark plug does not break.
#2. Remove The Spark Plug Wires.
It’s also a good idea to move all of the spark plug wires to give more access to the spark plug pits.
Make sure you mark each spark plug wire as you remove them so that you can reconnect them correctly later.
#3. Clean The Area Around The Stripped Spark Plug.
Using a slightly damp cloth, gently wipe around the the spark plug to remove any loose debris. If you have a portable vacuum cleaner with a narrow head you can use this to remove any lose dirt.
Don’t be tempted to use a blower or power washer as this will damage the spark plugs and nearby engine parts.
#4. Spray Lots Of Penetrant Spray And Wait.
This is probably the most important step in the entire process. Spray lots of penetrant (WD-40 works just fine) around the base of the spark plug where it meets the cylinder head.
Leave the penetrant to do its job for at least an hour. If you really want to increase your chances of successfully removing the spark plug, then I’d suggest leaving the penetrant fluid applied for at least 4-6 hours or even overnight.
#5. Gently Attach The Extractor Tool.
The next step is to correctly attach the extractor tool to the top part of the spark plug. It’s vital that the tool is attached properly so as not to break the spark plug.
Start by attaching the correct sized extractor tool to an extension bar. Most spark plugs require a 5/8″ or 16mm socket for removal. You will need the extension bar so that the extractor can reach down to the spark plug and to allow you to attach it correctly.
Locate the top of the spark plug and push the extractor socket gently on to the top of it. Try to stand directly over the spark plug so that you naturally apply direct downward pressure and not sideways pressure that may cause the spark plug to snap.
#6. Slowly Try To Turn The Tool Anti-Clockwise.
Now attach the wrench handle to the top of the extension bar. Gently apply a direct downward pressure whilst turning the wrench slowly anti-clockwise.
This first turn of the wrench will allow the extractor flute to grip the spark plug and it’s important that it sits square and pushed down as far as possible onto the spark plug.
#7. Slowly Continue To Remove The Spark Plug.
Once the spark plug has loosened from the cylinder block, then continue to turn the wrench slowly in an anti-clockwise direction whilst applying even pressure. Take your time, and keep turning the spark plug until is is completely unscrewed.
Once the spark plus has been removed use a torch to inspect the spark plug socket in the cylinder head for damage. Before you fit the a new spark plug, clean around the opening ensuring that nothing falls into the top of the engine.
Repairing the Damaged Threads
If the threads on the cylinder head are damaged, you’ll need to repair them before installing a new spark plug. Here are a few common repair methods:
Thread Chasing
Thread chasing involves using a special tool called a thread chaser to clean up the damaged threads. This tool has sharp cutting edges that remove any burrs or imperfections from the threads. Thread chasing can be effective for minor thread damage.
Helicoil Inserts
For more severe thread damage, Helicoil inserts are a common solution. These inserts are made of hardened steel and are designed to be threaded into the damaged area, creating a new, strong thread.
Helicoil inserts are a permanent repair and can significantly improve the strength of the threads.
Time-Sert Inserts
Similar to Helicoil inserts, Time-Sert inserts are another option for repairing damaged threads.
Time-Sert inserts are made of a special alloy that is designed to be stronger than the original threads. They are also self-tapping, meaning they can be installed without the need for a separate tapping tool.
Installing a New Spark Plug
Once the damaged threads have been repaired, you can install a new spark plug. Follow these steps to ensure a proper installation:
Step 1: Clean the Spark Plug Well.
Before installing the new spark plug, clean the spark plug well thoroughly. Remove any debris or dirt that may have accumulated in the well.
Step 2: Apply Anti-Seize Compound.
Apply a small amount of anti-seize compound to the threads of the new spark plug. This will help prevent the spark plug from seizing in the future.
Step 3: Install the Spark Plug.
Hand-tighten the new spark plug into the cylinder head. Once it is snug, use a torque wrench to tighten the spark plug to the manufacturer’s specifications. Do not overtighten the spark plug, as this can strip the threads.
Spark Plug Care Guide
Once you’ve successfully removed and repaired the stripped spark plug, you certainly don’t want to go through that again! Here’s a spark plug care guide to help you avoid future stripping issues.
- Use a Torque Wrench: This is the single most important prevention tip. Always use a torque wrench set to the manufacturer’s specified torque settings. Never guess or overtighten.
- Start by Hand: Always start threading spark plugs by hand. This ensures they are properly seated and prevents cross-threading. If it doesn’t turn easily, stop and re-align.
- Cold Engine Installation: Install spark plugs into a cold engine. This minimizes the risk of thread damage due to expansion and contraction.
- Anti-Seize Compound: For spark plugs going into aluminum cylinder heads, use a small amount of anti-seize compound on the threads. Be careful not to get it on the electrode. Note: some manufacturers (like Ford) specifically advise against anti-seize on certain plugs, as it can alter torque values. Always check your service manual.
- Proper Plug Type: Always use the correct spark plug type and heat range for your vehicle.
- Regular Maintenance: Follow your vehicle’s recommended maintenance schedule for spark plug replacement. Don’t leave them in too long, as corrosion and carbon buildup can make removal difficult.
- Quality Tools: Invest in good quality sockets and wrenches. Cheap tools can strip bolts and plugs.
- Consider Eco-Friendly Disposal: When replacing old spark plugs or parts from extraction, dispose of them responsibly. Many auto parts stores have recycling programs for metal and other automotive waste, contributing to a more eco-friendly how to get a stripped spark plug out process.
How much does it cost to fix a stripped spark plug professionally?
The cost varies greatly depending on the severity of the strip, the engine’s design (accessibility), and whether the cylinder head needs to be removed.
It can range from $200-$500 for a simple in-situ repair to $1000+ if the head needs to be removed or replaced. DIY methods, when successful, are significantly cheaper.
FAQs.
Q: Can I drive with a stripped spark plug?
No, driving with a stripped spark plug is highly risky. It can lead to misfires, reduced engine performance, and potentially allow exhaust gases or combustion byproducts to escape, damaging other engine components or the cylinder head further. Address the issue immediately.
Q: What if I can’t get the spark plug out?
If you’ve tried the common methods and the plug remains stubbornly stuck, it’s time to consider professional help.
Further attempts without the right expertise or tools can lead to more severe damage, like breaking the plug off inside the cylinder head or damaging the head itself.
Q: Is a Helicoil or Time-Sert repair permanent?
Both Helicoil and Time-Sert repairs are designed to be permanent solutions. Time-Sert is generally considered stronger and more durable due to its solid bushing design, making it a preferred choice for critical applications or high-stress environments. Proper installation is key to the longevity of either repair.
Q: How can I prevent stripping spark plugs in the future?
The best prevention is always using a torque wrench set to manufacturer specifications, starting plugs by hand to avoid cross-threading, installing them into a cold engine, and using anti-seize where recommended. Regular maintenance and using quality spark plugs also contribute to thread health.
Dealing with a stripped spark plug can be intimidating, but with this comprehensive how to get a stripped spark plug out guide, you’re now equipped with the knowledge and steps to tackle it.
Remember to prioritize safety, take your time, and don’t hesitate to seek professional help if the job becomes too complex.
Successfully fixing a stripped spark plug is a huge accomplishment for any DIY mechanic, saving you money and building your confidence under the hood.
Final Words
Spark plugs are responsible for making a gas engine run by shooting sparks and then igniting the mixture of gas and air in the cylinders, thus causing the pistons to not only move down but also create power that in turn runs your car.
Over time, spark plugs wear down or get stripped. When such a thing happens, you need to remove and replace them. Learning how to remove a stripped spark plug is really important because you’ll avoid costly bills from the car repair shop.
Hopefully, the above guide was helpful in assisting you to remove the spark plug stuck in the cylinder head like a pro.