Lawn mower engine design. Can You Run Mower Without Blade? – don’t do it

What are Lawn Mower Engines?

There are many varieties of lawn mowers and consequently, there are many kinds of lawn mower engines. Each one performs a special duty – some are great for residential lawns, others are better for commercial properties, and some are perfect for golf courses. Some are powered by gas and others are powered by electricity. Some are pushed and pulled and others are ridden upon.

Lawn mower engines are most commonly found in rotary push mowers and they, as a general rule, have internal combustion engines. Specifically, they usually are two-stroke cycle or four-stroke cycle engines. In addition, they typically are powered by gasoline and range from two horsepower (1.5 kW) to seven horsepower (5.25 kW). In general, they have a manual crank that starts their engines and a carburetor. Although, there are some models that have an electric start button. Some newer models even have a regulatory mechanism that stops the engine from being over-revved – great to elongate the life of the engine.

Riding lawn mowers are very popular. They have a seat and a wheel or other hand controls. Because the equipment is so heavy, it takes a high horsepower (kW) engine to propel it. Depending on whether it is going to be used for home or commercial use, riding lawn mower engines can range from 13 horsepower (9.7 kW) to 30 horsepower (22.4 kW).

Although most people assume that reel or cylindrical lawn mowers will not have an engine at all, it is not always the case. Both gasoline and electric lawn mower engines can be attached to reel lawn mowers to power the reels and blades. If an engine is attached to a reel mower, the engine or motor spins the reel and the person pushes the mower. Another form of a reel mower is one that is used to cut the greens on golf courses. Because they are large in size, a powerful engine is needed to move the mower properly.

Caring for a lawn mower engine is relatively easy. After the mower is used, wait for the engine to cool. Then, use a garden hose to clean the undercarriage of the mower of any grass, debris, and clippings. When the season is over, it is best to store the mower in a dry place. Doing so will lengthen the life of the engine. Then, drain the fuel and run the mower until the engine stops. By draining the fuel, it prevents it from aging and ruining the engine.

Other routine maintenance of lawn mower engines includes changing the oil at least once a year, replacing the spark plug once a year, and replacing the fuel filter and the air filter when necessary. For those individuals that are handy, the maintenance is rather simple; however, there are skilled persons who can do it for a small fee. Keeping the engine clean and well-maintained is an important part of owning any kind of lawn mower.

Although the kinds of engines in the various lawn mowers are many, most can be broken into two main categories: gas or electric. Electric engines are more expensive and usually have lower horsepower (kW). Gas-powered engines are more powerful and less expensive. Electric engines do not require the hassle of purchasing gas or disposing of the old gas at the end of the season. In addition, they do not pose any environmental concerns like their gas-powered counterparts. Gas-powered lawn mower engines emit high amounts of pollution without any regulatory concerns.

Dee is a freelance writer based in Colorado. She has a B.A. in English Literature, as well as a law degree. Dee is especially interested in topics relating to medicine, legal issues, and home improvement, which are her specialty when contributing to.

Dee is a freelance writer based in Colorado. She has a B.A. in English Literature, as well as a law degree. Dee is especially interested in topics relating to medicine, legal issues, and home improvement, which are her specialty when contributing to.

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Can You Run Mower Without Blade? – don’t do it!

Many people ask me about starting their mower engine without the blade, so much so, I wrote a post explaining all.

Many small engines are designed specifically for mowers and as such require the extra mass of a moving blade to help rotate the crankshaft on the compression stroke past top dead center (TDC). Starting such an engine without the blade may cause personal injury and damage the engine.

In this post, you’ll learn why most mower engines require a blade to run correctly. If you need video help, check out “Replacing mower blade video”.

Most mower engines won’t start without a blade attached.

Small Engine Types

There are two common engine configurations, the Vertical crankshaft, and the Horizontal crankshaft layout. Vertical and Horizontal crankshaft is self-explanatory. The orientation of the crank will naturally lend itself more suitable to one task over another.

Horizontal Engine

It’s not possible to turn a Horizontal shaft engine vertically and simply call it a Vertical engine. These engines have been designed to operate in their particular configuration. For example, most small engine oil systems are splash lube, it relies on splash paddles hitting a puddle of oil at the base of the engine. You can see the problem here. But the differences go deeper than that, as we’ll see shortly.

Horizontal small engines are designed to suit many applications, unlike vertical engines. The Horizontal engine is more common generally. They are best suited to driving power washers, water pumps, cement mixers, tillers, snowblowers, etc. They are not designed specifically for anyone single purpose and as such will run just as well with or without an attachment on the crankshaft.

Vertical Engine

Mower engines on the other hand are a little different. They are known as vertical shaft engines. Vertical shaft engines by their layout are perfectly adapted to sitting on top of a mower deck with a blade fastened to the crankshaft underneath.

Most of these types of engines are designed to have a blade fitted, meaning, the mass of the rotating blade is factored into the overall design of the motor. I say most mowers because some manufacturers employ a feature like Toro’s Spin Stop. They use a separate control lever to engage the blade. This feature allows the engine to run without the blade spinning, useful for propelling the mower across graveled areas.

Higher-end Honda mowers also sport this feature. If your mower has this feature then your engine will comfortably run without a blade attached. Likewise, tractor mower engines will run happily without blades attached, since they aren’t designed to have a blade fitted directly to the crankshaft.

Why Does Mower Need Blade To Start

Before explaining why a mower requires a blade, it’s helpful to know a little about the four strokes of an engine cycle. Once understood, the purpose of sufficient mass to rotate the engine becomes clear.

Stroke 1 Induction – As the piston travels down the cylinder the intake valve opens. Gas and air mixture enter the cylinder.

As the piston nears the bottom of the cylinder the intake valve closes.

Stroke 2 Compression – The piston meets resistance as it travels back up the cylinder, all valves are closed. Gas and air mixture is forced towards the combustion chamber at the top of the cylinder by the piston.

(It’s momentum, helped by the mass of rotating crankshaft, flywheel and blade that powers this stroke).

Stroke 3 Power – As the piston passes the very top of the cylinder travel (TDC), the plug fires and the explosion drives the piston downwards towards the bottom of the cylinder.

This of course also drives the blade which cuts the grass.

Stroke 4 Exhaust – This is the last of the four strokes of a complete cycle. The piston begins to travel back up the cylinder and the exhaust valve opens to allow spent gases to exit through the muffler.

As the piston reaches the top of the cylinder, the exhaust valve closes and the whole cycle begins again.

Mower Engine Needs A Rotating Mass

Flywheel Adds Mass

All small engines (vertical and horizontal) require a rotating mass to drive the piston when it’s not under power. This is especially true on the compression stroke, where the piston meets lots of resistance as it squashes the fuel mix into the combustion chamber.

To help the engine achieve sufficient rotational momentum, it employs weight in the form of a crankshaft, flywheel and of course, the blade is factored when the engine is designed for a mower.

If a moving object has sufficient mass (weight), it will carry momentum. Without the required mass rotating at a sufficient speed (mower blade spins at over 200 mph at the tip), the resistance the piston meets on the compression stroke would simply overcome the rotational force on the crankshaft and the engine loses its momentum. Firing the plug now easily causes the engine to reverse track, aka kickback.

Spinning Blade Adds Mass

Running Mower Without Blade Is Dangerous

Attempting to start a mower without a blade is dangerous, the lack of crankshaft momentum causes the engine to kick back. Kickback occurs when you pull the starter cord to start the engine and the cord is snapped from your hand sharply. The cord often whips you as it snaps back and sometimes breaks the pull handle. This can be a painful experience and is more commonly associated with a broken shear-key.

You can read more about a shear-key here.

Broken Shear-key

Running Mower Without Blade Risks Engine Damage

Running the mower engine without the blade risks damaging the crankshaft or shear-key. Blades aren’t universal, a mower engine is designed to run with a specific blade, by specific I mean not only correct length and width but also mass and lift.

As an engine approaches top dead center, and if it isn’t carrying sufficient momentum. As the plug fires, it causes the crankshaft to rotate in the wrong direction, snapping the cord from your hand as it does so. If you need video help, check out “Fitting mower shear-key video”, which covers the complete process from diagnosis to replacing, or check out a post I wrote here “Replacing a shear-key”.

Hey, I’m John, and I’m a Red Seal Qualified Service Technician with over twenty-five years experience.

I’ve worked on all types of mechanical equipment, from cars to grass machinery, and this site is where I share fluff-free hacks, tips, and insider know-how.

Will this Lawn Mower Run without an Air Filter?

And the best part. it’s free!

Proper maintenance for your mower is key to a working machine and a healthier lawn—and it all starts with the right refill. Get to know your lawn mower engine oil options here.

By Amy Lynch and Bob Vila | Updated May 27, 2021 10:13 AM

We may earn revenue from the products available on this page and participate in affiliate programs.

Q: I haven’t changed my lawn mower’s oil since last season, so I’m feeling rusty. Remind me: What type of oil can I use in my lawn mower?

A: You’re not alone. In fact, this bit of lawn mower maintenance happens so occasionally that some people forget to replenish lawn mower oil in the first place. It needs replacing after every 20 to 50 hours of operation, depending on your mower’s specifications. If your yard is small, that might mean as few times as once a year! But, while this task is infrequent, it’s also important to change the oil properly—starting with the correct type of oil for lawn mowers—to keep your machine running.

Two types of oil can go into operating lawn mowers, but your mower’s size, type, and capacity might help determine which of these two is the better option. Even the climate you live in can make a difference when the time comes to change or add oil, since each type of oil for lawn mowers has its own recommended temperature range. If you live in a place that frequently heats up to more than 100 degrees, for example, it might be wise to choose an oil made to withstand a wide range of temperatures.

Different Kinds of Lawn Mower Engine Oil

According to a survey of consumers conducted by Briggs Stratton, the world’s largest producer of gasoline engines for outdoor power equipment, 48 percent of those who buy automotive oil for their mower believe that automotive oil and small engine oil are one and the same.

In fact, lawn mower engine oil (as well as oil for other small engines) might actually be the only type your mower can tolerate. Using motor oil meant for a tractor or car can clog and disable some units completely due to its higher viscosity.

Always check your manufacturer’s specifications first. No owner’s manual handy? If yours has a Briggs Stratton engine, you can use the company’s interactive tool to determine the best oil for your specific lawn mower’s engine based on its make and model, motor type, and local climate. Talk about a shortcut! Otherwise, at a minimum, it’s important to keep a few guidelines in mind.

Lawn Mower Oil Types

Not all oils are equal, and it helps to get to know the subtle differences to determine the best oil for a lawn mower and avoid a costly mistake. In general, there are two main types of oil: motor oil and small-engine oil. Brands vary in their formulas, with some being regular oil, some a mix of regular and synthetic and some fully synthetic. Older oils typically were one weight or grade only, but newer oils have a viscosity rating added.

• SAE 30 is a single-grade, or straight weight, oil with a viscosity rating of 30 and is safe for small, air-cooled engines, typically older models.
• SAE 10W-30 is a multigrade engine oil that can work in cold temperatures, as well as hot, for a fairly balanced temperature range.
• SAE 5W-30 is a multigrade engine oil with a low viscosity to flow better at colder temperatures (than 10W-30), but protect the engine enough in heat.
• Synthetic SAE 5W-30 is a synthetic (artificial) lawn mower oil that works for both cold and warm weather. Synthetic oils tend to be more stable across temperature ranges than conventional oils.
• Vanguard 15W-50 is a brand of fully synthetic engine oil designed for commercial applications that operates at temperatures ranging from 20 to 130 degrees.

Motor Oil SAE Viscosity Grade

The Society of Automotive Engineers (SAE) grades motor oils by viscosity. Viscosity loosely relates to weight, or thickness, and more accurately as a measure of how the oil flows at specific temperatures. In colder temperatures, thinner single-grade oil performs better in engines.

It gets a little more complicated with multigrade engine oil. Look at the first number, with a W (10W, for example) as a measure of flow in cold temperatures. The W stands for winter (not weight). The lower this number, the less viscosity an oil will have at colder temperatures, and the better it will flow. Too thick when the engine starts, and it won’t flow through and protect those critical engine components.

The higher number that follows (the 30 in 10W 30) refers to viscosity at higher operating temperatures and in hot weather. Multigrade oils typically are designed to flow in a range of temperatures to match conditions. Some oils have additives that also keep viscosity steadier in cold or heat.

How to Choose the Best Oil for Your Lawn Mower Engine

When choosing the right lawn mower oil type for your mower, your best bet is to check the manufacturer recommendations. Also consider the engine type (such as 2-stroke engine), oil viscosity, and average temperatures where you live.

Motor Oil for Four-Stroke Engines

Four-stroke engines tend to power heavy-duty equipment, but are reliable and your best bet for larger lawns. These engines are common in large and/or riding lawn mowers as well as some push mowers. Even so, be sure to check your manufacturer’s manual or website for specific instructions on which grade of motor oil to use, since—much like a car—the engine might be sensitive to certain additives.

Oil and gas are kept separate in a four-stroke engine. Oil with a grade of SAE-30 is often a safe bet, but it’s still worth confirming since a lawn mower is no small investment. You can buy SAE-30 motor oil online (view example on Amazon), at any auto parts store, from most gas stations, and in the automotive section of a hardware store.

Small Engine Oil for Two-Stroke Engines

This type of engine is most commonly found in smaller and older push mowers, plus other small engines, like on weed trimmers and chainsaws. Its popularity as a preferred lawn mower engine has decreased some over the years as four-stroke units have become more common. Louder and smokier than their four-stroke counterparts, two-stroke motors can keep running no matter how steep an angle you’re trying to tackle (think: hilly or sloped terrains).

Two-stroke engines are lighter and cost less, too. And, since they use the same fill port for both gasoline and small engine oil, two-cycle motors require owners to mix them together in a specific ratio such as 32:1 or 50:1—refer to your operator’s manual for the correct gas-to-oil ratio.

These oils typically have additives to help clear carbon deposit and minimize wear, among other tasks. Find small engine oil online (view example on Amazon) or in the lawn and garden section of any hardware or auto parts store.

Know when to change your lawn mower’s oil.

A brand new mower might need an oil change after the first 5 hours of use; refer to your unit’s manual. Beyond that, small motors might need an oil change every 25 hours of use or thereabout, while larger motors typically can last up to 50 hours before requiring oil replacement.

A handful of factors can increase the frequency of oil changes, including extreme dust and dirt, rough terrain, frequent mowing of wet or muddy grass, and even a hot climate—conditions in which the engine is forced to work harder. If you have a large yard (or if you mow a small yard frequently), use a dipstick or clean cloth to check the lawn mower engine oil level before each use once it’s run beyond 20 hours or so.

Even if the mower hasn’t hit the 20-hour mark at the end of a season, make a point of changing your oil each spring, before your first mow. Avoid overfilling the mower by checking the oil level with a dipstick.

FAQ About Lawn Mower Oil

What kind of oil do you use in a lawn mower?

The oil type depends on the engine type, typical operating temperatures, and especially the recommendations of the lawn mower manufacturer. In general, small-engine oil that is a mix of oil and fuel works in two-stroke engines, and straight oil typically works for four-stroke engines. Factors such as temperature affect which grade to choose.

Can you use regular motor oil in a lawn mower?

Lawn mowers with four-stroke engines might do fine with regular motor oil, but always check the manufacturer documentation to make sure. Some automotive oils are too high in viscosity and meant for larger engines, so don’t assume that more is better. Many deluxe models of push mowers and riding mowers use regular motor oil. Two-stroke engines cannot use motor oil; they need a mix of fuel and oil specially designed for small engines.

What’s the best oil to use in a lawn mower?

The best oil to use in a lawn mower is the one recommended by the manufacturer. Viscosity and whether the oil is synthetic or regular oil can vary based on climate, conditions, and engine type.

Can I use 10W30 instead of SAE 30 in my lawn mower?

No, it is not recommended. Most engines that call for SAE 30 are older models of mowers with engines designed for straight weight oil. These models were designed before multigrade oil became available, so you should not substitute with the multigrade option.

Final Thoughts

Lawn mower oil is essential to keeping your mower running efficiently and effectively, and use of the right oil, plus regular oil changes, can protect the life of the mower’s engine. Take the time to find out the best oil for your lawn mower based on the mower’s model and recommendations of the manufacturer. Also consider operating conditions, viscosity, and type of engine.

A little prep avoids irreversible damage caused by forcing the wrong oil through your lawn mower’s engine.

Who Makes The Most Small Engines For Lawn Mowers?

In 2019, these companies combined to make 16.46 million small engines bound for the best lawn mowers in use in push mowers, ride-on mowers, pressure washers, concrete mixers, portable generators, water pumps and other power equipment.

Take Note: All information and data on this page was gathered from company publicly available SEC Filings, Annual Reports, Financial Presentations and from paid access to statistics and comprehensive study reports on the global lawn mower markets.

Here’s a breakdown bar graph of how many small engines each company produced in 2019:

Briggs Stratton makes the most small engines that end up on lawn mowers (nearly 8 million), followed by Honda (6.3 million), then Kawasaki (1.25 million) and Kohler (nearly 1 million).

It should be noted all of Briggs small engines are small engines whereas companies like Kohler also make a ton of larger diesel, propane and marine engines for use in large generators and boats.

At this point – you may be wondering – what portion of these small engines end up on lawn mowers?

Good question. Because these small engines also end up in portable generators, pressure washers, snow blowers and other power equipment.

Here’s a graphic showing the percent of small engines ending up in lawn mowers vs. other power equipment.

• 42% of small engines made by “the big 4” end up in lawn mowers.
• 58% go to other power equipment.

Out of 16.5 million small engines made almost half are going to lawn mowers – push and ride-on versions.

We love our lawn mowers – that’s for sure.

Briggs Stratton

Briggs Stratton filed for bankruptcy on July 20, 2020.

They were wholly bought by private equity firm KPS Capital Partners on September 23, 2020. KPS Capital Partners also owns LifeFitness (and others) and used to own Taylor Made Golf (and others).

On the customers facing side nothing changes. But now they have solid financial footing and no debt worries.

How did Briggs Stratton go bankrupt?

In the next bar chart you will be able to get a picture why they went bankrupt.

From 2009 to 2020 they have received less small engine orders every single year. And engines are what they do.

First, realize Briggs Stratton only makes engines once they have received an order for them.

So if a lawn mower company orders 100,000 small engines – only then does Briggs start manufacturing them.

In 2009, 2010 and 2011 they received orders for between 11.29 and 11.37 million small engines each year.

In 2013, 2014 and 2015 order for Briggs small engines had declined to between 9.6 and 9.7 million engines.

And the final dagger came when Covid-19 hit and companies and people stopped buying things. In 2020, Briggs Stratton only received order for 6.9 million small engines – almost half of their 2010 production.

Check out the decline in the below chart:

Briggs Stratton small engine facts:

B S make 4 types of engine:

• Small vertical shaft
• Horizontal shaft
• Large vertical shaft
• Commercial engines

Small vertical shaft engines (12 models)

B S most popular engines are their small vertical shaft engines used on walk-behind lawn mowers.

Horizontal shaft (4 models)

The horizontal shaft motors are used for small garden tractors, generators and pressure washer systems.

Large vertical shaft engines (4 models)

Used on all types of machines but mainly riding mowers.

Vanguard Commercial engines (24 models)

The premium offering from B S is their Vanguard brand of engines. These are for commercial-duty power equipment and come with premium specs like cast iron cylinder sleeve and extended warranty.

Briggs Stratton power product sales

Briggs Stratton reports financials in two segments:

Engines are small engines and Products are Briggs branded equipment like pressure washers, snow blowers and portable generators.

The Engines Division is usually about 60% of sales.

Also, some Briggs products may use (from time-to-time) Honda, Kohler or Kawasaki engines. Mainly though, the Product Division buys Briggs small engines from the Engines Division.

Here is a chart showing the total Briggs Stratton powered product sales (in billions of USD) including small engine sales.

Again you can see the decline in sales leading up to bankruptcy in 2020.

Let’s now look at Honda small engine units made and power product sales over the years.

Honda

Honda’s revenue breakdown in 2021 was as follows:

And that 2% Power Products Division was around 3 billion USD. Yeah, Honda big.

Honda’s Power Products division includes:

• Honda general purpose engines
• Lawn mowers
• Generators
• Water pumps
• Snow blowers
• Tillers
• Trimmers
• Outboard boat motors

Honda documentation tells us how many general purpose small engines Honda makes per year.

In this bar chart from 2003 to 2022 we can see how many small engines Honda made each year.

Keep in mind motorcycles are a separate division within Honda. So these small engines are all for power equipment and have nothing to do with scooter or dirt bike engines.

In the graph you can see Honda engine production fluctuated quite a bit between 2003 and 2011. Then between 2011 and 2022 have had steady small engine production between 5.5 and 6.5 million units per year.

Upon further digging it looks like the 2010 drop in production

Honda small engine facts:

Honda makes 7 different series of engines:

• GC/GCV – Residential – 160cc – 20cc
• GS/GSV – Light commercial – 187cc
• GX/GXV – Commercial – 7 different sizes: 98.5cc – 389cc
• V-Twin – Commercial – 688cc
• iGX – Commercial – 2 models: 270cc and 389cc
• iGX/V-Twin – Commercial – 2 models: 688cc and 770cc
• Mini 4-Stroke – Residential – 4 models: 25cc – 50cc

Honda has a relatively small lineup of small engines with only 20 total models available. They do this so they can FOCUS on those 20 and make them better each year.

Honda power product sales

Honda power equipment is known for its durability, reliability and price tag – it costs the most because it is the highest quality.

We surveyed 29 landscape/lawn care and rental shop companies (via email, instagram and website contact forms) to show what power equipment they used and trusted.

Every single rental shop owner said they would not buy and rent out any other brand than Honda.

Because with regular maintenance they would never break and cause downtime – losing them money not being able to be rented out.

The landscape company owners were less united and mentioned brands like Toro, Scag and John Deere.

Regardless, Honda makes great equipment and it shows in their multi-billion dollar power products business.

See the bar chart below the sales from 2012 to 2022.

Compare this progression to the Briggs Stratton chart above.

In 2012, Honda and Briggs powered product sales are identical. Then Honda starts to pull away and Briggs Stratton is in decline.

Now let’s look at Kawasaki – the Japanese brand famous for the Ninja motorcycle and Jet Ski personal watercraft.

Kawasaki

Kawasaki is a diverse company. Here is their sales breakdown for the 2021 financial year :

And that Motorcycle Engine division (23% of Kawasaki sales) is 3.34 billion USD.

Kawasaki Motorcycle Engine division – unlike Honda – includes their motorcycles. And motorcycles/scooters/ATVs are all more expensive than general purpose small engines. So although it may seem Kawasaki is on par with Briggs and Honda in small engine production, they are far behind in terms of unit sales per year.

Check out this bar graph showing the progression of Kawasaki small engine production from 2010 to 2022.

• Kawasaki engines are used in about 60% of riding mowers for professional use in the U.S.
• 90% of Kawasaki general purpose small engines are sold to U.S. mower manufacturers
• In 2019, it is estimated nearly 2 million riding mowers were sold in the U.S.

Looking back at the chart of Kawasaki small engine units made: Even though they are far below Briggs and Honda in units sold, they still dominate the riding mower market. Briggs and Honda FOCUS more on the push mowers and other power equipment.

You will usually see riding mower companies sell their mowers in tiers with different pricing. These tiers are usually:

• Tier A – Best Quality – With Honda Engine –
• Tier B – Best Overall – With Kawasaki Engine –
• Tier C – Best Value For Money – With Kohler or Briggs Stratton Engine –

There is NO BETTER WAY To SHARPEN A BLADE Than THIS!!

Kawasaki small engine facts:

Kawasaki small engines are purpose built for riding mowers. Here’s there lineup:

• FX – 14 models – 15 HP – 38.5 HP
• FT – 4 models – 20 HP – 26 HP
• FS – 6 models – 14.5 HP – 24 HP
• FR – 4 models – 18 HP – 24 HP
• FJ – 2 models – 179cc
• FH – 1 model – 764cc
• FD – 3 models – 25 HP – 31 HP

Kawasaki motorcycle and powered products sales

Kawasaki has a motorcycle and power product division which includes all their fun stuff:

• Motorcycles
• Dirt bikes
• ATVs
• Side x sides
• Jet skis
• General purpose engines

Like other companies they are pushing hard into electric vehicles – battery powered stuff.

Below is a bar graph showing Kawasaki sales of motorcycle and power products from 2010 t0 2022.

• This division inside Kawasaki made 2.51 billion USD in 2021.
• In 2021, Honda’s power products division made 2.47 billion (not including motorcycles.
• Honda’s motorcycle division made nearly 15 billion in 2021 (Honda sells massive amount of scooters and lower powered motorcycles to Asia.

Now let’s move on to the final member of the “big 4” lawn mower engine companies: Kohler.

Kohler

Kohler is the 57th largest private company in the U.S., according to Forbes.

It is estimated they had revenue of 7 billion in 2020.

Given they are a private company and don’t have public records, we have to do some estimation to get their small engine sales data.

• The key document we found is a 2006 United States Tax Court filing between the grandchildren of Herbert Kohler (the founder).
• It tells us that Kohler’s business operations are divided into 4 divisions: Kitchen and Bath (70 – 75% of revenue), Power Systems including small gas engines and large generators (15 to 20% of revenue), Interiors (6% of revenue) and finally Hospitality (4%).

Calculating Kohler Small Engine Unit Sales

Key piece of information: the Power Systems division (small engines for lawn mowers etc. and generators) accounts for 15 to 20% of the 7 billion revenue.

Assumptions and calculations:

• Let’s split the difference and use 17.5% for the Power Systems division portion of total revenue
• 7 billion x 17.5% = 1.225 billion
• But this number includes all their engines and all their generators. They sell diesel engines (not used on lawn mowers) they sell marine engines (not small engines for power equipment) etc.
• Let’s say 20% of their Power System division is strictly small engines for lawn garden equipment like lawn mowers.
• 1.225 billion x 20% = 245 million
• From our other calculations of Honda and Briggs power product sales and small engine unit sales we know the unit cost of a Briggs Stratton engine is 125 and Honda is 400. For Kohler we will split the difference and say Kohler engine average unit cost is 262.50.
• 245 million divide by 262.50 equals 933,000 Kohler small engine units sold in 2019.

Yes, this is an educated guess.

But after further analysis we feel it is representative.

Kohler small engine facts:

Over the years Kohler has introduced 190 different models of small engines:

• 59 residential and 131 commercial engine types
• 83 horizontal shaft and 105 vertical shaft
• 75 single cylinder and 115 twin cylinder

As of 2022, 104 models have been retired.

Today, Kohler still has the widest range of small engines on offer with 86 different options.

What Brand Of Small Engine Is The Best?

Between Honda, Kawasaki, Briggs Stratton and Kohler which is the best small engine maker?

The general consensus is all the big 4 are great as long as you do regular maintenance.

But, this is the most common way to rank them from best to last:

Kohler, Briggs Stratton – Best value (affordable)

The easiest way to answer this is to look at what lawn mower brands choose.

In this chart we can see a lot of brand overlap.

Many lawn mower brands will have models of lawn mower with different engine brands.

Their premium model may have a Honda or Kawasaki engine and their more cost friendly model may have a Briggs Stratton or Kohler engine.

Take a look – what surprises you:

• Briggs Stratton small engines are used by the most brands. This is most likely because they make a ton of affordable 2.5 – 5 HP engines great for budget push mowers.
• Honda makes their own bestselling brand of lawn mower so their engines are most used on their own brand power equipment. Many other brands will have a model with the Honda engine as well as a model with a Briggs or Kohler or Kawasaki engine.
• Kawasaki are the most popular engine on riding mowers. Brands like Dixie Chopper, Scag and Bad Boy mowers use them the most. Kawasaki are often thought as the middle ground better expensive high quality (Honda) and budget value for money (Briggs and Kohler).
• Kohler small engines are used on many riding mowers and some push mowers.

Other Notable Companies

Kubota

Kubota is a multi-billion dollar Japanese company selling heavy equipment, tractors, engines, vending machines and sewage treatment equipment.

Their engines range in size from 250cc to 6 litres with both diesel and gasoline models.

Kubota’s main sellers are large diesel engines for agricultural-duty tractors.

They offer residential zero turn riding mowers with Kubota, Kawasaki and Kohler small engines. In terms of lawn mower engines they are not producing at the same level as the big 4.

Yamaha

Yamaha makes small engines for its power products: Generators, pressure washers, pumps.

They also make engines for their motorcycles, scooters, waverunners, ATVs, golf carts, side-by-sides, outboard boat motors and snowmobiles.

Yamaha acquired Subaru Industrial Power Products from Fuji Heavy Industries in 2017. Subaru Industrial Power Products produces small general purpose engines which brands like Ryobi choose for their gas pressure washer and lawn mower.

Yamaha’s Other Products Division had sales of 500 million in 2021. This division includes golf carts, generators, snow blowers, electric wheelchairs and multipurpose engines. So as you see Yamaha is a major player in the small engine industry – just not lawn mower engines.

Subaru

Subaru small engine brand – Subaru Industrial Power Products – was acquired by Yamaha in 2017. All production was discontinued (Sept 30, 2017) and transferred over to Yamaha Motor Corp.

Generac

Generac Power Systems makes standby and portable generators, and pressure washers. They are the #1 brand for home backup generators.

They are a major player in the engine industry. However, they only make engines to put in their equipment.

In terms of size, they generate around 3 billion USD in revenue per year.

Champion Power Equipment

Champion is a power equipment braking mainly dealing in portable generators. In recent times they have expanded to log splitters, pressure washers, snow blowers and more.

They are popular because they offer budget options and are usually the most affordable product in the category.

They small engines used are made in China and are Champion branded.

STIHL

STIHL is the largest chainsaw manufacturing company in the world. STIHL makes their own 4-stroke petrol-oil mix engine they call the 4-MIX. It combines the advantages of the 2-stroke and 4-stroke and is perfect for their chainsaws and other garden equipment.

They are a private company and do not share their financials.

Kipor Power

Kipor offers 15 models of small engines from 2.5 HP to 16 HP. And you will find some riding mowers with Kipor engines.

But Kipor Power is mainly making engines for their generators and construction machinery.

Tecumseh

The current company called Tecumseh makes HVAC (heating, ventilation and air con) products. However, they used to be a well-known gasoline small engine maker and maker of the Snow King brand of snow blower.

In 2007, Tecumseh sold off their engine and power train businesses to Platinum Equity LLC. Platinum later sold the power train biz to Husqvarna and the engine biz to Certified Parts Corp.

In 2010, Certified Parts Corp. partnered with Liquid Combustion Technology (LCT) to make small engines for outdoor power equipment. And re-introduce the Snow King line of snow blowers. This new partnership produces engines under the Lauson, LCT and Snow King brands.

Liquid Combustion Technology

LCT makes over 100,000 small engines per year ranging in size from 79cc to 420cc.

They have offices in South Carolina, Shanghai and Sydney.

They make engines under the LCT brand as well as the Lauson and Snow King brands.

Sources

• Kohler Gasoline Engines. Listing of all Kohler gas engines.
• Honda Small Engines. Listing of all Honda gas engines.
• Briggs Stratton Engines. Listing of B S lawn mower and power equipment engines.
• Kawasaki General Purpose Engines. Listing of Kawasaki engines.
• Kohler United States Tax Court Filing. Breakdown of 4 Kohler business divisions.
• Honda Financial Results. All the financial data from 2013 to 2022 for Honda.
• BGG: Briggs Stratton Corp SEC. SEC Reports for Briggs Stratton.
• Kawasaki Earnings Report. 2022 financial data for Kawasaki.
• General Purpose Engine For Lawn Mowers FX850V-EFI. Facts from Kawasaki about their share of the riding mower market.
• KPS Capital Partners, LP, Active Investments. Facts about PE firm that bought Briggs Stratton.

About your guide: Jamey Kramar is a certified Lawn Care Manager (NALP) and a Mechanical Engineer by trade. He has been writing about outdoor power equipment for 11 years and has been quoted in NYTimes, Popular Mechanics, HowStuffWorks, iFixit, Realtor.com, and more. He spends his spare time disassembling things and also building an off-grid cabin at his 200-acre property.