Taiwan Leading Hand-Tool Maker

How to Select the Right Spark Socket

  • 2015-07-17

A spark plug is an essential component in your engine cylinder. Whether you drive a car or a motorbike, when a spark plug is damaged, all you can do is to wait for the tow truck. A quality spark plug can help you to avoid this embarrassing situation. How do you install a high-quality spark plug? The first step is to choose the right spark plug socket from a leading manufacturer like Tien-I.

Before selecting a spark plug socket, one must have a fundamental understanding of sizing. Based on different engine designs, spark plug hexes come in different sizes and screw lengths. Common structures and sizes are shown in the image below.



(Left: 13/16" (20.63mm) Right: 5/8" (15.87mm))

Common hex screw sizes are listed in the table below, along with their respective dimensions in inches and millimeters.


Various spark plug brands have their own sizing methods. This table for Japanese NGK spark plugs includes a column for the outside diameter length of the hex screw. Another column lists the spark gap size, be determined by the thickness of the wall of your socket.


Now that you know how to select the right spark plug socket, let’s look at a few Tien-I spark plug sockets designed for different situations.

Regular spark plug socket


Regular spark plug sockets are suitable for most DIY repairs. You just need to make sure you select the right hex screw and socket. Tien-I’s regular spark plug socket has rubber inside, which ensures you can remove the spark plug without damaging the part. However, this kind of socket requires the use of an extension bar to prevent the socket from falling into the cylinder of the engine.

Deep Spark Plug Socket


Tien-I’s deep spark plug socket is specially designed for use with narrow and deep cylinders. To enable it to reach all the way into a narrow deep shaft, the deep spark plug socket is thinner and longer than the standard one.

Universal Joint Glow Plug Socket


Tien-I’s Universal Joint Glow Plug Socket is designed with a flexible angle to make it easy to access complicated cylinders.

T-handle spark plug socket


A T-handle spark plug socket has all the advantages listed above and is designed for repairing the engine. It eliminates the need for additional tools such as ratchets or extension bars.


T-Handle Spark Plug Socket

Installing or removing the spark plug on a motorbike or car involves varying levels of difficulty according to the model and brand. Especially when you’re dealing with complicated modern car engines, you may require a special spark plug socket. We don't recommend conducting DIY repairs on your engine at home, as it's easy to run into trouble if you don't select the right replacement. We would suggest seeking advice and help at a professional tool shop if you are not familiar with spark plug brands.

Interested in Tien-I spark-plug sockets? Please feel free to contact us.