Where is the Lawn Mower Spark Plug

Checking and replacing spark plugs is an important step in the regular maintenance of a small engine and in resolving problems with a lawn mower, snow blower, and other outdoor power equipment. Follow this three-step guide to get through the process or go to the section.

Before performing any repair or maintenance on a small engine, be sure to check your engine manual for specific part numbers and safety precautions.

Where is the spark plug in my small engine?

Follow this step-by-step guide with images for finding spark plugs in different Briggs engines & Stratton. The spark plug key can help avoid engine damage when removing these parts for cleaning or replacement.

Arrangement of a spark plug in engines with a lateral arrangement of cylinders

These engines, also known as lower valve engines or side valve engines, are commonly used in pedestrian mowers and pressure washers.

Arrangement of a spark plug in engines with the top arrangement of the valve

Where is the Lawn Mower Spark Plug

Spark plug types chart & clearance for Briggs engines & Stratton

Now that you have found the part you want to replace, you can use the chart below to find the original Briggs spark plug & Stratton and clearance recommendations.

Be sure to use the correct spark plug! Although several different spark plugs can be screwed into the engine, using the wrong spark plug will lead to performance problems and possible internal damage to the engine.

Spark plug & gaps

These engines, also known as lower valve engines or side valve engines, are commonly used in pedestrian mowers and pressure washers.

Type of spare part Spark plug replacement options from
Briggs Part Number & Stratton
Spark plug clearance
Standard resistor 796112S
0.030 inch
Electromagnetic suppression (EMF) 697451 0.030 inch
Series® Extended Valve Engine Spark Plug
Candle platinum
5062 (5062D, 5062H)
0.030 inch
Champion CJ8, RCJ8, RJ19HX, J19LM and RJ19LM 796560
5062 (5062D, 5062H)
0.030 inch
Champion RJ19LMC is used in
Quantum engines
591868 0.020 inches – engines manufactured after code date 110630x
0.030 inches – manufactured before code date 110701xx
Champion RJ2YLE are used in Quantum 625, 675 series engines, & 725 manufactured after code date 110701xx 799876
Not for Quantum engines manufactured before code date 110701xx or other lower valve engines
0.020 inch
"Sururefire" RJ2YXLE at Craftsman Smooth Start (MRS) 591040 0.030 inch

If you have a Quantum engine, be sure to check the code date before servicing the engine.
>> Find your engine model number, code date, and more.

Video: Where is the Lawn Mower Spark Plug

Creating a beautiful lawn and maintaining it in order is not an easy task. And to make it easier, you need a reliable assistant – a lawn mower. There are many good and different models on sale. And although everyone has the same purpose, in a number of parameters they differ from each other. Let’s try to figure them out.

Lawn mower

What are lawn mowers?

By the way of moving lawn mowing machines are divided into:

  • Manual (trimmers) that are held in hand when mowing,
  • Wheeled hand, which you need to carry on the lawn,
  • Self-propelled.

By type of drive motor distinguish mechanical, gasoline and electric lawn mowers.

Mechanical Wheel Mowers easy to operate, it does not need electricity or gasoline, but significant muscular effort is needed. They are environmentally friendly, silent and allow you to adjust the height of mowing the grass. The cutting mechanism is a cylindrical knife driven by wheels. Such a tool is good for caring for a young lawn, as the low speed of rotation of the knife prevents pulling out grass with a fragile root system.

Mechanical Wheel Mower

And we will consider gasoline and electric lawn mowers below.


Hand Lawn Mowers (trimmers) fit for regular lawn mowing in a small area even with an uneven surface, as they can mow at any angle. The trimmer is a holder bar, at the lower end of which is a cutting device with fishing line. And with high power – additionally with a circular knife. The mower hangs on a belt on the operator’s shoulder, literally making it easier for him to work.


Trimmer can be equipped electric or gasoline engine. Electric is located on the lower or upper end of the rod, and gasoline – only on the upper.

A protective cover limits the mowing edge and protects the legs of the mower from injury. During operation, the left hand holds the handle of the bar (adjusting, if necessary, the height of mowing the grass), and the right hand holds the handle with the engine control button.


The main advantage of trimmers – the ability to mow grass in uneven areas and close to bushes and trees. But maintain the same mowing height at the same time will not work.

Electric trimmers

The electric trimmer is powered by a household power outlet. To his merits can include:

  • Light weight
  • Environmental friendliness (there are no exhaust gases and noise).

Disadvantages of the electric trimmer:

  • Binding to a network (outlet),
  • The presence of a stable voltage,
  • Forever disturbing cable on the lawn
  • Low power.

And the cable itself has a limited length: you can’t squint far from home.

Electric trimmer

Battery Trimmer – the same as the electric one, but the engine does not work from the outlet, so you can mow at any distance from the house. This is his basic convenience. However, the mowing area is determined by the capacity of the battery.

Petrol trimmers

The gas trimmer is designed to work in large areas. Therefore, it is especially in demand by summer residents, and owners of country estates, and workers in urban utilities. However, working with it requires some preparation.

Petrol trimmer

This type of lawn mower is distinguished by an enviable mobility, increased power and practicality. It can be used for mowing not only lawn grass, but also weeds and bushes. And professional models are able to cut stems up to one and a half centimeters thick.

However, even with a small fuel tank, such an assembly:

  • Weighs quite a lot,
  • Requires a mixture of gasoline with oil,
  • Pollutes the environment with exhaust fumes,
  • Makes a noise.

But it can work in any weatherat.

The convenience of mowing grass with a trimmer is determined by several points, and one of them is the location of the engine.

Trimmers engine bottom on sale a lot. Most often they rechargeable low power. They overheat quickly, so they require frequent interruptions in work. Protection against moisture and mechanical stress is poor. They cannot work on morning dew and immediately after rain, otherwise a short circuit may occur.
Engine Trimmer

Trimmers engine top more practical, more balanced and more powerful, require less mowing effort, and therefore more comfortable in operation. They have good cooling (less overheating), and, therefore, greater performance.

Engine Top Trimmer

Among the trimmers with an upper engine, I especially want to highlight knapsacks. Their engines are secured behind their backs (like a schoolbag), which significantly reduces the load on the hands and much less restricts movement.

Knapsack petrol trimmer

A nice trimmer option is anti-vibration system. It allows you to reduce the vibration load on the shoulders and hands, protects the arms and back of the mower.

Powerful gas trimmers to reduce the burden on the hands equipped with ergonomic handle, similar to a bicycle wheel. On the right handle are buttons to control the operation of the tool. When buying a trimmer, make sure that the handle and button layout on it are comfortable for you.

Comfortable bicycle handle