Briggs and Stratton Spark Plug Chart for All Lawn Care Machines

by Jack Grover
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Selecting the accurate Briggs and Stratton spark plug size is indispensable for optimal vehicle performance. Keep in mind, though, that the appropriate size will depend on your specific vehicle type and model.

With numerous spark plugs available, it can be confusing to choose the right one for you. So, what is the most common Briggs and Stratton spark plug gap size? Although various gap sizes exist, a Briggs engine’s spark plug gap size for a standard resistor is .030”.

To help you navigate this complex landscape, we’ve compiled a Briggs and Stratton spark plug chart detailing more sizes. Additionally, we’ve included some extra facts to aid in your understanding of this essential component.

Let’s break it all down for you.

Briggs and Stratton Spark Plug Chart: A Quick Overview

Selecting the right spark plug size plays a crucial role in ensuring stable fuel economy, reliable starting, and consistent spark. There are various spark plug sizes tailored to specific engines, making it essential to choose the correct size for your engine. 

In Briggs and Stratton’s case, the spark plugs are categorized under their respective models, with most of them determined by the gap size.

To assist you further, we conducted research and created a spark plug gap guide for chainsaws, mowers, and snow blowers — check out our findings below.

ConcernSpark Plug Hex (SPH) SizeSpark Plug Reach (SPR) Size
Riding Mower16mm12.7mm
Bestseller No. 1
Briggs & Stratton Spark Plug - OEM Replacement Part# 591868
Briggs & Stratton Spark Plug – OEM Replacement Part# 591868
Briggs & Stratton 591868; New OEM Spark Plug; Genuine Briggs & Stratton Part; Replaces Old Briggs # 799876
$4.99 Amazon Prime
SaleBestseller No. 2
Bestseller No. 4
Briggs & Stratton Spark Plug for OHV Engines 5092K
Briggs & Stratton Spark Plug for OHV Engines 5092K
Part# 496018s in display packaging; Replaces Briggs & Stratton Service Part #496018S; For Selected OHV Engines


It’s crucial to use the correct spark plug for your engine.

While several different spark plugs may fit into the engine, using the wrong one can lead to performance issues and even internal engine damage. Always double-check that you’re using the appropriate spark plug for your specific engine to avoid any potential problems.

When dealing with platinum, iridium, or twin-tip spark plugs, do not attempt to change the gap, as these types of plugs have fine electrodes that are easily damaged. Adjusting the gap on these spark plugs may compromise their functionality and cause harm to your engine.

Following these guidelines will help prevent performance problems and safeguard your engine from unnecessary damage.

Below, we take a closer look at this chart to help you determine the appropriate spark plug size for your Briggs and Stratton engine-equipped machine, ensuring optimal performance and longevity.

Riding Mower Spark Plug

To ensure proper electricity flow through a spark plug, it’s essential to choose the correct size for your riding lawn mower. In most cases, the appropriate size ranges from 14 to 16 mm. If the size exceeds this range, your mower may not function correctly.

Briggs and Stratton spark plugs offer this size range with improved performance. They provide a 16mm SPH size and a 12.7mm SPR size, ensuring compatibility with your lawn mower. Moreover, the thread size is consistently 14mm, so you won’t face any issues in that regard.

When selecting a spark plug for your lawn mower, Briggs and Stratton presents three options: platinum, NGK, and Champion.

While the NGK spark plug series work well for lawn mowers, the Champion series is considered somewhat superior. However, platinum spark plugs are often regarded as the best option. In our research, the platinum series received high praise from various forums.

For aftermarket spark plugs, consider checking out RCPW. Before purchasing any spark plugs, though, make sure to consult the spark plug chart for Briggs and Stratton engines.

Additionally, try cross-referencing between the reference code imprinted on the spark plug to ensure you select the correct size for your riding mower.

Snowblower Spark Plug

When examining the Briggs and Stratton spark plug cross-reference chart, you’ll find that it’s quite similar to the chainsaw chart.

However, there is one noticeable difference: the reach of the spark plug for a snowblower is approximately 9.5mm, while for a chainsaw, it’s around 12.7mm. The hex size remains the same at about 20.6mm.

This size is compatible with most snowblowers on the market.

For optimal consistent sparks, the center electrode should have a copper core. In terms of compatibility, the Champion spark series is considered the best option for a snowblower. While you can also use the platinum series, they are more suited to snowblower engines and provide a longer lifespan.

The thread size in each of them is 14mm.

Always ensure you’re using the correct spark plug size for your snowblower to maintain optimal performance and avoid potential damage.

Chainsaw Spark Plug

Selecting the appropriate spark plug for your chainsaw is crucial, as using an incorrect one may lead to malfunctions. In general, a chainsaw requires a spark plug with a 20.6mm hex size and a gap size of .030 inches. The heat capacity should be around 8.

Fortunately, Briggs and Stratton manufacture spark plugs specifically designed for chainsaws, featuring a standard 14mm thread size to ensure a proper fit. For chainsaws, Briggs and Stratton recommend using platinum, NGK, and Champion spark plugs due to their effectiveness and ability to prevent damage.

If you cannot find the required spark plug size in your chainsaw’s manual or are unable to contact the supplier, Briggs and Stratton can provide assistance based on your vehicle’s model.

How to check the spark plug size?

The process is quite simple — locate the spark plug reference code on the spark plug itself.

For Briggs and Stratton engines, consult the Briggs and Stratton spark plug cross-reference chart to determine the actual spark plug size.

Additionally, you can visit Briggs and Stratton‘s official website to find out the appropriate spark plug thread size for your chainsaw engine. Although thread sizes are primarily standard, this information will help ensure compatibility.

We strongly advise against using a different size spark plug, as it can interfere with the pistons and cause engine damage.

Also Read: Briggs and Stratton Carburetor Troubleshooting Guide

Here’s a Handy Tutorial You May Need!

How to Determine a Suitable Spark Plug for My Lawn Mower?

If your lawn mower’s spark plug is malfunctioning and needs a replacement, it’s essential to find the right one. You can’t just pick any random spark plug, as it may not match your mower.

To identify a suitable spark plug for your lawn mower, consider these factors:

  • Spark plug type. Various spark plugs come with different materials, features, quality, and longevity. For instance, copper spark plugs are recommended for small lawn equipment with low voltage. In contrast, platinum spark plugs work well with heavy-duty equipment and offer better endurance.
  • Spark plug size. Spark plug sizes vary according to equipment type, model, and other factors. To find the right size, take the old plug and match its dimensions when purchasing a new one. Additionally, your equipment model or user manual can guide you toward the correct size.
  • Gap size. The gap where the spark plug is placed affects your choice significantly since not all spark plugs can fit every gap size. Be sure to consider this factor when selecting a new spark plug for your lawn mower.
  • Thread size. It’s crucial to measure the thread size of your current spark plug, as choosing the wrong one can lead to oil accumulating around the plug. Pay close attention to this detail when making your selection.
  • Heat range. This factor determines how much temperature or heat a spark plug can endure. As engine temperatures rise higher, opt for a spark plug with a higher heat range, preferably between 8 to 10.


What spark plug do I need for my Briggs and Stratton?

When selecting a spark plug for your Briggs and Stratton engine, consider the 496018S. This spark plug is standard for most Briggs and Stratton engines and should suit your needs.

However, if you’re interested in aftermarket spark plugs, there are several options to choose from, such as NGK, Champion, or Boss spark plugs. Regardless of the brand you select, it’s crucial to ensure the spark plug gap and thread size are compatible with your Briggs and Stratton engine.

Remember to consult your engine’s user manual or check with the manufacturer for specific recommendations suited to your particular model.

What is the spark plug gap on a 5-horse Briggs and Stratton?

For a 5-horse Briggs and Stratton engine, the recommended spark plug gap size is .030″.

This gap size is not only specific to this particular engine but is also considered standard for various other components.

What types of spark plugs do Briggs and Stratton take?

The majority of Briggs and Stratton engines rely on the 496018S spark plug, which is known for its wide compatibility. These spark plugs feature a gap size of 0.30″, making them suitable for various engine models.

What spark plug does a 17.5 Briggs and Stratton take?

For a 17.5 Briggs and Stratton engine, the recommended spark plug is the 691043 OEM plug. 

This specific spark plug has been designed and manufactured to cater to the unique requirements of the 17.5 models.


Selecting the correct spark plug size is crucial, as your engine’s performance relies on it. A high-quality spark plug ensures optimal fuel economy and generates consistent sparks, resulting in a stable and efficient engine.

If you use a Briggs and Stratton engine vehicle or tool, it’s essential to find a compatible spark plug.

In this article, we provided a Briggs and Stratton spark plug chart to help you make an informed decision when replacing a faulty spark plug in your chainsaw, blower, or small engine machine. 

Keep in mind that using an incompatible spark plug can cause damage to your engine. Therefore, always refer to the chart and follow the recommendations to choose the right one for your specific needs.

By paying attention to these details and selecting the appropriate spark plug for your Briggs and Stratton engine, you can maintain its performance, extend its lifespan, and prevent potential damage.

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