Socket For Spark Plug

What Size Socket For Spark Plug?

Do you feel more vibration, or can’t get blissful acceleration from your vehicle than previous? The problem may link to your vehicle’s spark plug. So, to check out the spark plug, you need to remove that from your vehicle. While removing, you can use a regular deep well socket but that may damage the good spark plug.

That’s why you need to choose the right size socket to deal with this important component. So, what size socket for spark plug? Well, in my following discussion, you will find enough information regarding your query. So, let’s get started.  

A Brief Overview of Spark Plug Socket

Before discussing the spark plug socket, I want to notify you of the spark plug. Spark plug plays an incredible role in your vehicle’s performance. It is used to deliver eclectic current from an ignition system to the combustion chamber. 

Over time the spark plug becomes unusable, and it needs to change with a new one. So, what tools do you use then? 

Actually, you can’t use the traditional tools because of the spark plug’s delicate and sensitive nature. That’s why you need a unique tool named spark plug socket, which is designed to deal with the spark plug. 

The manufacturer uses two possible interiors. With those interiors, you can carefully grab the plug without causing any damage. 

You will find magnetic sockets and rubber inset sockets to handle the spark plug. The magnetic socket comes with magnets to ensure the perfect holding of the plug, and the rubber inset socket is used to place the plug. 

A Chart of Spark Plug Socket Size

You will find different HEX sizes in the spark plug. Hex indicates the diameter or the socket of the center of the spark plug. With the help of a hex, you can turn on the spark plug and undo it.

You will find different options; among those, people generally use 14,16,18,21 mm sockets.

The spark plug is considered an essential tool for all types of vehicles such as motorcycles, cars, even lawn mowers. 

Although there are various sizes of the spark plug, but most of them haven’t any usage or can be used only in rare cases like the old model of the BMW car. However, while buying a spark plug socket, you need to consider the premium-made socket to withstand pressure. 

Use in VehicleThe size of the spark plugThe size of the socket
Motorcycles, scooters, small engines (Briggs & Stratton, Koehler), Many newer vehicles (GMC, Nissan, Chevy, Subaru)5/8 inches or 16 mmThe same as spark plug size
Older vehicles (especially the large engines)13/16 inches or 20 mmThe same as spark plug size
Small engines or Lawnmowers3/4 inches or 19 mmThe same as spark plug size
Motorcycles18 mm3/8 inches
Newer Asian and European vehicles, Ford, Motorcycle9/16 inches or 14 mmThe same as spark plug size
BMW or MINI18mm bi hex11/16 inches
The older model of BMW11/16 inches or 8 mmThe same as spark plug size
Older vehicles, Tractors, aviation7/8 inchesThe same as spark plug size

The Guideline of Choosing the Right Size Socket for the Spark Plugs

 How could you choose the right size socket for the spark plug? Let’s reveal this from the following discussion.

 Step 1: Is a wrench perfect to carry on?

You don’t need a spark plug wrench for some small engines; instead, the spark plug wire boot can be removed simply. Then it would help if you used a crescent wrench or a box-end for removing the plug. Nevertheless, you need an extension or a deep socket for the car if the spark plug lies into the deep of your car’s engine head.

Step 2: Choose the right size socket

Finding the right size spark plug for a specific engine model isn’t complex. You can easily find it using the internet.

Typically, the service center uses two standard sizes of sockets, such as 13/16-inch and 5/16-inch. Although there are various sizes of spark plug sockets, but those two will help you complete most projects.

If you see the spark plug socket comes in a weird size, then you can use a deep socket. Here it would help if you cared about damaging the plug while removing it. However, to measure the bolt, you can use calipers.

Step 3: Buy or borrow the spark plug socket.

When you are going to purchase or borrow a spark plug socket, you will find various options along with different price ranges. If you have the option to visit nearby local auto parts or dealership stores, you can visit there; otherwise, an online marketplace like Amazon could be the best solution. 

Step 4: What style will you take, Magnet Style or Rubber Insert?

While purchasing the spark plug socket, you must keep the quality on the top list. Let’s clarify using the following example. You will find a rubber insert in the spark plug, which is used to protect the plug’s ceramic insulator. That protection is necessary during installing and reinstalling. 

Also, you will find even magnet-style sockets which will retard the spark plug from dropping and breaking. Whatever all those, the choice basically depends on the user’s demand. However, another tool called magnet extension can be used to remove the plugin from the vehicle’s engine. 


You will find various types of sockets on online and offline platforms. From those alternatives, it may be trickier to find the perfect one. That’s why I recommend two different socket sets, such as:

  • Powerbuilt 640855 3/8-Inch Drive Spark Plug Socket Set.
  • CARBYNE Spark Plug Socket Set – 5 Piece, High Visibility 3/8-Inch Drive SAE & Metric Spark Plug Socket Set.

You may check out the following reviews of these two different socket sets. 

1. Powerbuilt 5 Piece 3/8 in. Dr. Spark Plug Socket Set

If you are looking for a perfect size spark plug socket set to remove the spark plug safely, then you can choose Dr. Spark Plug Socket Set? It is a socket set with different sizes including SAE 5/8″, 3/4″, 13/16″, metric 14mm, 18mm. Hopefully, it’s features will make your DIY much more effortless. 

Powerbuilt 3/8-Inch Drive Spark Plug Socket Set, 6 Point, Deep Thin Wall, 5 Piece Metric and SAE - 640855, Grey
  • Sockets include 5/8-Inch, 3/4-Inch, 13/16-Inch, 14mm, 18mm
  • 6 point deep well thin wall mirror polished chrome vanadium socket with dual grease rings


My picked spark plug socket set comes with some strong, beautiful and helpful SAE and metric ⅜ inch drive spark plug sockets. The inside section of these sockets has precision chamfered hex faces hence, make it easier to fasten. The exterior design offers a sleek chrome finish which makes the size marking easy to read. 

You may need blissful grabs to prevent slipping and round-off. Well, my picked socket set is featured with Z-Drive 6 point hex pattern that offers blissful grabs and then reduces slipping and round-off. 

Plus, the rubber construction inside the socket ensures a little tight grabbing of the spark plug. How durable is this socket set? Well, the manufacturer uses premium chrome vanadium steel, which makes this socket set much more sturdy. 


  • The premium chrome vanadium steel makes this socket stylish and sturdy.
  • You can quickly identify the marking through its jumbo size forged size marking.
  • To reduce rounding here lies Z-Drive grips and turns flat surfaces of fasteners.
  • The manufacturer ensures ANSI standards using precision built. 


  • The packaging isn’t satisfactory. 

2. CARBYNE Spark Plug Socket Set – 5 Piece, High Visibility 3/8-Inch Drive SAE & Metric Spark Plug Socket Set 

CARBYNE makes my 2nd picked spark plug socket set. Here include five different socket sizes, such as 5/8 inch, 3/4 inch, 13/16 inch, 14 mm, 18 mm. Let’s see which specifications make it ideal for dealing with the spark plug. 


The first thing I will notify you of is the construction. Well, the manufacturer uses Chrome Vanadium Steel which makes it durable and sturdy. While dealing with the spark plug, you need to ensure secure holding. To ensure a secure hold of the spark plug, here used a rubber retaining ring. 

Size matching is indeed an essential task for the user. The manufacturer ensures high visibility of the marking to ease the working. Another feature called mirror polished finish ensures professional quality. 


  • To ensure secure grabbing here lies rubber retaining rings. 
  • The manufacturer provides high visible marking to ease the use. 
  • The Chrome Vanadium Steel makes the construction highly durable. 
  • Made in the USA.


  • No tellable cons are found herein. 

Why I Choose Powerbuilt 640855 and CARBYNE Spark Plug Socket Set?

The manufacturer uses chrome vanadium steel which makes the above mentioned socket sets sturdy enough. Both socket sets include 3/4-Inch, 5/8-Inch, 13/16-Inch, 14mm, 18mm. Moreover, to ensure secure holding, those spark plug sockets offer rubber retaining ring holds. 

Furthermore, the size marking is visible enough to ensure easy identification. Another feature worth noting is that my selected socket sets come with a durable mirror finish.

The Guideline of Removing Old Spark Plugs

Here are the steps to remove each spark plug:

  1. Get ready for removing the spark plug

Before removing the spark plug, you need to cool down the engine. Then, apply compressed air to blow away all the loose dust and dirt from the spark plug. After that, you need to remove the breather hose.

Note: The wire could damage if you grab the wire and yank that from the actual wire. So, it will be better to hold it by the boot and pull it out. Moreover, if you find it difficult to remove, you can use nose ring pliers.

Now, you can access the spark plug. Again, it would help if you cleaned debris and dirt after removing the spark plug because the debris could have fallen into the engine.

  1. Remove the spark plug

Now, take a spark plug socket to grab the spark plug socket. 

Note: To protect the ceramic insulation from getting cracked, you need to ensure the socket has a little rubber boot while buying. 

Also, you can connect a long extension to touch the spark plug, and then you can lose that plug by hand.

  1. Finding the correct size spark plug

Now, it’s time to install a new one. For that, you need to compare the old one with the new one to ensure both are the same. This part is important because the extra tall top of the piston could hit the spark plug and thus damage the engine.

The next point that demands attention is the gap of the plug is correct in size. This is because the too-wide gap may retard the spark. On the other hand, the too-small gap may cause a weak spark; thus, it may not ignite the fuel efficiently. You can get the gap size from the manual or from the hood of the car.

  1. Apply necessary lubricant

Firstly, you need to take anti-seize (a lubricant) and apply it to the spark plug threads to ensure the threads don’t get stuck inside the engine. 

Applying that lubricant may not be necessary for some spark plugs so, check the vehicle’s manual or the spark plug’s manual. Again, you need to apply dielectric grease to the ceramic part of the spark plug. 

After applying that lubricant, you can keep your spark plug safe from corrosion and prevent high voltage from leaking out. Also, you can apply dielectric grease inside the spark plug boot using the cotton swab.

  1. Install the spark plug

While installing the spark plug, you need to tighten the spark plug correctly. If you tighten it too much, the threads could be damaged. On the other hand, if you don’t tighten correctly, the spark could come loose and blow from your vehicle’s engine.

Now, stick that spark plug in the socket and then drop that down in the right place. You can tighten the spark plug by hand, and you don’t need to use an impact gun or a wrench.

Note: If you face the spark plug is hard to tighten, you need to back it out and start over to avoid cross-thread.

If you feel a problem while tightening by hand, you can do that using a torque wrench. One point is worth noting is not all the vehicle offers an easy to install sparking plug. 

Some cars come with a very impact engine that provides a spark plug on the side of the engine. There, you won’t find any easy access so you need to remove the battery to get the access. 

This type of engine offers no plug wires; instead, here lies a coil on the plug. So, remove the coil and the trick using a universal joint extension. Another engine type is the transverse engine which offers a spark plug on the backside. To reach on that engine’s spark plug, you can do two things, like:

  • You can reach there from your vehicles underneath to see if there is any access to the plug.
  • Another way is removing the wiper blade cowl of your car; therefore, you will get much space to get your arm’s back.

The Process of Cleaning a Spark Plug 

Over the years, our vehicle’s spark plug becomes dirty. It would help if you cleaned that to minimize more vibration, improve acceleration, improve fuel economy and ensure no misfiring and no smoky exhaust. 

Here we visualize the easy process of cleaning a spark plug. So, clean your vehicle’s spark plug whenever you service your vehicle. In the following section, I will tell you how to complete that cleaning process.

  • Firstly, you need to find out where your spark plug is located. We mentioned the removing process in the previous section; hopefully, you can disconnect the spark plug.
  • Once you remove the spark plug, you will see the present condition of the spark plug. If you explore a lot of carbon that is deposited on the electrodes of the plug, you need to clean that immediately.
  • To complete the cleaning process, you need to keep some items handy. Those items will be a plastic cup, some patrol, a brush, a polis paper or sandpaper, and a spark plug gauging.
  • Now, take the plastic cup and pour a small amount of petrol on it. 

Note: Patrol is considered ideal for dissolving carbon quickly. 

Once you take that liquid, now dip the spark plug into the liquid and leave it for some time.

  • After leaving the spark plug into the liquid for some time, hopefully, you see the difference in the patrol color. You may see the color is darker and intense. That indicates the spark plug is cleaned correctly.
  • Now, take a bristle brush or plastic to clean the hard carbon. After that, you need to take polish paper or sandpaper to clean the hard carbon from the electrodes.
  • After going through the above steps, you will discover a shiny spark plug. Now, take a gauging tool to check the gap between the electrodes. After finding the gap, now check that amount with the manufacturer’s manual.
  • Finally, you need to clean the area where you install the spark plug before installing your cleaned spark plug.

Final Thought:

Hopefully, the discussion notifies you of all of the required information that you need to deal with a spark plug. You already know how vital a spark plug is for your vehicle. 

So, clean and replace when you encounter the issues related to the spark plug. I wish you happy driving and see you in any next article. 

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