Lawn mower carburetor issues. How To Locate and Clean The Carburetor On A Lawn…

Where is the Carburetor on a Lawn Mower? (Every Mower)

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I’ve always enjoyed using my cordless walk-behind push mower – no pesky cord to haul around and no gas to fill in the tank. But when I need a surge of power to complete larger jobs with ease, my go-to choice undoubtedly is my robust 140cc Briggs Stratton gas push lawn mower.

The downside however of using a gas-powered lawn mower is maintaining the many different parts like the air filter, spark plugs, hoses, and several other parts under the hood including the lawn mower carburetor.

Of all these aforementioned parts, the lawnmower carburetor is often the most overlooked but is in fact one of the most important parts of a mower just like a lawn mower engine that requires a fair bit of maintenance including annual maintenance.

What is a LawnMower Carburetor?

All gasoline-powered lawnmower engines are fitted with a carburetor. Similar to your car or truck engine, a carburetor helps run the small engine of a push lawn mower, self-propelled lawnmower, or riding lawnmower.

What Does a Lawnmower Carburetor Do?

The only goal of a lawnmower carburetor is to ensure that the right mixture of fuel and air enters the engine cylinder to trigger combustion.

This component of a lawnmower adjusts the balance of air and fuel based on myriad different factors including the amount of time the engine has been running, your speed, and the type of terrain you’re mowing.

Unlike automobile systems, a carburetor of a lawnmower doesn’t contain any throttle butterflies (a pivoting flat valve controlled by the gas pedal) but contains a rubber-type push bulb, through which fuel is primed when the bulb is depressed several times on a push-type lawnmower.

The fuel from the fuel tank flows through the bulb via a hose into the carburetor, which typically allows gas to drip into the carburetor bowl.

The engine creates a suction on the carburetor which mixes the gasoline with air at a specific ratio. After the carburetor has been primed, you can use the pull rope to start the engine.

What Does a Lawnmower Carburetor Look Like?

Most lawnmower carburetors look similar, with a small metal component complete with levers and springs and a distinct bowl shape under the carburetor body.

The carburetor float bowl accommodates the fuel and provides a continuous supply of fuel to the carburetor mixture as required.

The float bowl of a lawnmower carburetor can be drained with either the onsite drain bolt or screw without dismantling the whole system.

Where is the Carburetor on a Lawnmower?

This depends on the type of lawnmower you’re using, whether push, self-propelled, or riding lawnmower.

Where is the Carburetor on a Push Lawnmower?

Just as the name suggests, a push mower is any type of mower that you walk behind and push. The carburetor of a push mower is tucked away neatly behind the air filter at the side of the machine.

If you can locate the air intake filter or air filter of a push lawn mower, you’re one step closer to finding its carburetor. Depending on the machine, the air filter of a push mower is typically encased within a metal or plastic shroud and secured by a screw or with snap fittings.

Where is the Carburetor on a Riding Lawnmower?

The carburetor of a riding lawnmower is located just beneath the hood under the engine blower assembly so you’ll have to undo the hood latches of the engine hood to access it.

Similar to walk-behind mowers, the carburetor of a riding lawnmower is located behind or below the air filter, so once you remove the filter, you can spot it easily.

Signs a Lawnmower Carburetor is Dirty or Damaged

Old Gasoline

Old gasoline is the biggest enemy of a lawnmower carburetor regardless of the type of engine whether Briggs Stratton or brands including John Deere.

Your lawnmower will still run on old gasoline but it won’t offer the same top-notch performance that you’re used to.

This is why it’s highly important to empty the lawnmower gas tank when storing the machine for the off-season because old gasoline creates what is known as shellac in the fuel system.

This shellac blocks the inner workings and the air and fuel jets in the carburetor, which further prevents the fuel and air from passing through it.

A clogged gas line can be detrimental to the entire fuel system including the fuel filter, and mower air filter, and may even emit black smoke, which indicates that the machine is “running rich,” or burning too much gasoline.

The only solution for a gummed-up carburetor is a thorough cleaning, which involves removing the carburetor – a task you can do at home rather than visiting a lawn mower engine repair shop.

How to Get Rid of Old Gas in Lawnmower?

Before getting rid of the old gasoline from the lawnmower, check to see if it’s contaminated by pouring some in a glass container, pouring some fresh gasoline in another container, and then comparing them alongside.

If the old gasoline is darker or has a sour smell than the fresh gas, it is probably losing or has lost its efficacy.

Ideally, it’s best to get rid of the old gasoline from the lawnmower completely, but you can try diluting it with fresh gasoline to see if the performance improves.

You can transfer the old gasoline from the machine with a funnel into a jerry can or plastic can jug.

Engine Won’t Start

There could be several reasons why your lawnmower engine won’t start, most notably a dirty air filter, loose, dirty, or disconnected spark plug, and/or fuel not reaching the engine, which may be caused by a faulty carburetor or fuel filter.

If you’ve cleaned the air filter and checked that the spark plug and spark plug cable are connected securely, and you’re still facing the issue, making a few adjustments to the carburetor may help.

There may be many issues with the carburetor such as it’s dirty, the diaphragm is cracked or distorted, and/or it’s simply not getting the proper mixture of air and gasoline.

Your lawnmower’s carburetor and engine are protected against debris, dirt, and grass clippings by air filter guards. It is always a good idea to ensure they are clean and in perfect working condition:

• Check and clean the air filters and reinstall them in the machine.
• Next take a look at the vented fuel cap, which is designed to release pressure, allowing fuel to flow from the tank to the carburetor. Remove the gas cap to break the vacuum, then reattach it to see if this resolves the issue.

Engine Hunts at Idle or High-Speed

If your mower revs erratically, also dubbed as hunting or surging, the most likely cause is an incorrectly adjusted carburetor.

The good news is that most lawnmowers including John Deere have two screws that allow you to make adjustments to the carburetor yourself.

One screw adjusts the idle mixture while the other controls the idle speed. Since every lawnmower is different, refer to your owner’s manual for the location of the idle adjustment screws, start the mower and allow it to run for roughly 5 minutes, and make the screws looser or tighter until the machine runs and idles smoothly.

Lawn Mower Leaking Gas

A lawn mower leaking gas could mean several maintenance issues such as an open carburetor cover, carburetor housing, or carburetor float.

Another reason for carburetor fuel overflow is a stuck carburetor float, which is engineered to regulate the flow of fuel into the carburetor bowl through a simple mechanism.

There are a few potential fixes for this issue including adding a carburetor cleaner to your fuel, tapping the carburetor bowl light with the rear end of a screwdriver, and blowing compressed air through the carburetor bowl drain hole.

Engine Lacks Power at High Speed

Apart from old, bad fuel, another reason why the engine of your lawnmower may lack power at high speed is a dirty carburetor. In most cases, cleaning your lawnmower’s carburetor should resolve the issue.

How to Clean Lawn Mower Carburetor?

Experts say that you should check and clean your lawnmower’s carburetor at least a few times a year. The reason for this is simple – as you use your mower, grass, twigs, and other debris can make their way into the lawnmower’s carburetor, and eventually into the engine.

However, your carburetor will suffer breathing issues if the air filter is dirty, so the first thing to do is check the air filter to ensure it is free from any dirt and debris.

How to Find Your Lawmmower’s Carburetor?

Since every lawnmower isn’t built the same, the best way to find your mower’s carburetor is by referring to the user guide that came along with the machine. But here are a few simple steps to locate the carburetor of your lawnmower.

Before getting started, it’s important to ensure that the mower is in a stable position and safe location and will not roll off.

• Place the mower on a flat surface and make sure it is turned off completely. If you’re trying to locate the carburetor of a riding lawnmower, set it in a gear or engage the parking brake just like you would when parking a vehicle on a slope.
• Next, release anything that is making the mower’s internal components inaccessible such as hood latches. Most, if not all push lawn mowers don’t have a hood so can skip this step. This step applies to riding lawnmowers.
• Locate the air intake and the air filter, which are usually found on the side or top of the engine. The air intake and filter are set within a housing, which is either square or round shaped and has slits or holes in the top.
• Detach the filter housing which is attached to the carburetor via latches or screws.
• Locate the fuel line that comes from the gas tank to the carburetor. Undo the small clamp to detach the fuel line from the carburetor.

How to Remove a Lawnmower Carburetor?

To clean a lawnmower carburetor, you’ll have to completely remove it from the machine. You can usually do so with tools such as an adjustable wrench and/or a pair of needle-nose pliers. You may have to remove the engine cover as well depending on your lawn mower model.

• Turn off the fuel valve or make a crimp in the fuel line, and remove it from the carburetor. A little fuel may spill out at this time so you should dress appropriately for the job.
• Detach the choke and throttle linkages from the carburetor throttle lever, and remove the carburetor from the mounting bolts using a sliding motion.
• Unthread the screw to remove the carburetor bowl.
• Release the float pin and carburetor inlet needle.

How to Clean a Lawnmower Carburetor?

Once you’ve removed the carburetor from the lawnmower, you can use a carburetor cleaner to remove grime and fuel, and a dry rag to clean the external parts of the carburetor.

If you notice any signs of rust, get rid of them with sandpaper or a rust remover. Allow all the parts to dry and reinstall them and the carburetor back on the lawn mower.

If your carburetor is showing signs of physical damage, you may have to replace it with a new one instead of reinstalling the old one back on the machine.

How to Clean Lawn Mower Air Filter?

If you keep your lawnmower’s air filter clean, you will have less dirt and debris getting into the carburetor.

Your lawn mower’s air filter is in fact the first line of defense against dirt and debris that stems from the mowing process and prevents dirt from entering the engine via the carburetor.

It’s a good practice to clean your lawn mower’s air filter every 25 working hours or whenever you notice a dip in performance. Replace the air filter if damaged or after 300 hours of operation.

• Shut down the mower before getting started with the cleaning process, and make sure all the parts have come to a complete stop and have cooled down. Note: You should never operate a mower without an air filter as doing so will cause serious damage to the machine and yourself.
• Disconnect the spark plug wire and remove the protective screw that secures the mower’s shroud (covering) over the air filter. The exact location of the air filter could vary by model but most commonly is located near the top of the engine, and is protected by a shroud.
• Remove the air filter and take a closer look at it. Your lawnmower could be fitted with one of three different types of air filters:

• Foam air filter
• Paper air filter
• Dual-element air filter.

If you have a paper air filter, gently tap it on a flat surface to knock off any loose dirt and debris. Next, hold it up to a bright light source and if the paper blocks a considerable amount of light, then it’s time to replace it but don’t try and clean it further.

A foam lawn mower air filter should be replaced if there are any signs of crumbling or visible brown or yellow staining. If it’s in good condition, you can go ahead and clean it.

For a hybrid air filter, refer to the manufacturers cleaning guidelines. But usually needs to be replaced if it’s become stiff, brittle, or significantly stained.

Cleaning a Lawnmower’s Foam Air Filter:

• Washing: You can wash your lawnmower’s foam filter in the wash sink or with a garden hose to get rid of stubborn dirt. If it’s extremely dirty, use dish detergent to remove the dirt but be sure to rinse the soap out thoroughly.
• Drying: Let the filter air dry under the sun, after which you can oil it. You can apply oil with your hands or directly pour it over the foam filter. But don’t get carried away as you don’t want the oil dripping into the mower.
• Re-installing: Before reinstalling the air filter, clean the housing and the shroud with a dry cloth and not with a compressor because it could force dirt and debris into the carburetor and engine. Reinsert the air filter and make sure it fits snuggly into its dedicated slot. Lastly, replace the shroud but be careful not to tear the filter. Don’t forget to reconnect the spark plug, so you can start your lawnmower.

How to Perform Lawn Mower Maintenance?

Maintaining your lawn mower will improve both its performance and service life. Lawnmower maintenance can be carried out at any time of year but the two best times are before the first mow of the season and at the end of the season when it’s time to retire the mower.

Many people choose to take their mower to a professional repair shop for maintenance but these simple checks and fixes can be performed in the comfort of your home.

Since every lawnmower model is different than the other, it’s best to refer to your owner’s manual for maintenance instructions but here are some common tips to keep your mower in tip-top shape.

Replace the spark plug

Removing the spark plug ensures that the mower doesn’t accidentally start. A lawnmower spark plug should be changed every mowing season, after 25 hours of use, or if the mower won’t start.

• Start by disconnecting the spark plug lead.
• Clean the area to prevent any debris from seeping into the combustion chamber when you remove the plug.
• Use an appropriate spark plug socket to remove the spark plug.
• If there are any light deposits on the plug, clean them with a soft cloth.
• Replace the plug if there are any damaged electrodes.

Change the oil

You should ideally change the oil in your mower every 50 hours of operation or after every mowing season. Most mowers come with a drain plug that allows you to drain the oil from the mower. If your mower didn’t come with a drain plug, simply flip the mower over on its side and allow it to drain via its fill hole.

Make sure to replace the oil with the right type of lawnmower oil, but 10W30 is the grade suitable for most lawnmowers.

Drain the fuel tank

If your lawnmower won’t start, the common culprit is old gas. Lawnmower gas can go stale and lose its volatility in as little as 30 days and leaving gas in the tank when not in use can eventually corrode the fuel tank.

Remember to drain the fuel tank at the end of each season and refill it in the spring, and take all the necessary precautions while performing this task.

Clean the mowing deck

The mowing deck is perhaps the most used component of a mower but is also the most overlooked when it comes to cleaning and maintenance.

It’s a good practice to clean the mowing deck every time you finish cutting the lawn. Dirt, cut grass, and debris can accumulate onto the area above the blades, aka the mowing deck, and once it dries, becomes incredibly hard and difficult to remove.

You should perform a thorough mower deck cleaning at the end of the growing season, which entails removing the spark plug and cleaning the mowing deck and blades thoroughly.

Check the tires

Regardless of the type of mower, whether walk-behind mowers or riding lawn mowers, it’s important to check the tires to ensure they’re in good condition and are free from chips and damage.

Here’s an informative video on how to remove a lawnmower carburetor and the steps to maintain and repair a lawn mower:

How To Locate and Clean The Carburetor On A Lawn Mower? | A Beginners Guide

Like a car engine, the carburetor on a lawn mower helps the engine run. It ensures that a proper mix of gas and air enters the engine cylinder to allow for proper combustion, increasing overall fuel efficiency. In addition to overtime wear and tear, the carburetor of a lawn mower is also prone to damage from the lawn debris that can clog up the air filters, thus limiting the carburetor and lawn mower’s function. In this article, find out where is the carburetor on a lawn mower.

Keeping the carburetor of your lawn mower clean, well-maintained and in good shape is very important. It is a great way to save yourself some money, increase the lifetime of your mower and avoid unnecessary headaches and hassles down the road.

However, mower engines are quite compact, and most people often find it very difficult to locate various engine components, especially the carburetor.

Generally, the carburetor of a lawn mower is located behind the air filters, and it is often blocked from the view. So, you can start by looking for a square-shaped or circular filter housing. This filter housing usually contains a foam or paper filter. In addition to that, you can also locate the carburetor by tracing the fuel pipeline coming from the gas tank of your mower.

That said, lawn mowers come in a range of shapes and sizes. Depending on the lawn mower you have and its manufacturer, the location of the carburetor can vary.

So, you will need to understand a lot more about mower carburetors before you can precisely locate them, and we are here to help. So, let’s get started!

Lawn Mower Carburetor 101

Before we get into locating and fixing the carburetor of a lawn mower, it is important to understand what a carburetor is, how it works, what it looks like and why taking care of a lawn mower carburetor is essential.

What Is A Lawn Mower Carburetor?

The carburetor is an essential part of a gasoline-powered lawn mower’s engine. It regulates the flow of fuel from the gasoline tank and air from the environment in a correct combination. However, unlike the carburetor system used in a vehicle, the carburetor of a lawn mower is generally placed in a horizontal position.

In addition to that, the carburetor of a lawn mower also does not have any throttle butterflies. The carburetor is the lungs of a lawn mower, and it is a complex device with multiple connections. These connections typically include air lines, fuel lines and exhaust lines.

What Does A Carburetor Do In A Lawn Mower?

You might already know that any gasoline-powered engine burns fuel to generate power. However, what you might not know is that the fuel must be mixed in a correct ratio with air to yield maximum energy and fuel efficiency.

This is where the carburetor comes in; the carburetor of a lawn mower determines how long the engine has been running, the speed at which the mower is moving, the type of train that you are crossing and then adjust the balance of fuel and air accordingly.

If the carburetor of a lawn mower is not working correctly, the engine of the mower can still run; however, the fuel efficiency and engine power will be significantly reduced.

How Does A Lawn Mower Carburetor Work?

The carburetor of a lawn mower has two chambers. One chamber is known as the carburetor’s bowl, which stores fuel that will be injected into the second chamber, known as the combustion chamber.

As you might have already guessed by now, fuel mixes with air and burns in the combustion chamber.

A float pin in the carburetor’s bowl regulates the amount of fuel that enters the combustion chamber. In the combustion chamber, a spark plug ignites the air and fuel mixture, which produces thrust that, in turn, pushes the piston of the mower’s engine.

The piston then rotates the crankshaft, and this is how the blades on a mower spin.

What Does A Carburetor On A Lawn Mower Looks Like?

The carburetor of most lawn mowers looks very similar. Usually, it is a medium-sized metal component with springs and levers.

Carburetor can be rectangular, round or bowl-shaped. If you hold a carburetor in your hand, you will notice that it has two main openings. One opening is for air intake, and the other is for the exit when.

However, not all lawn mower carburetors look similar. For example, carburetors are now available in the market that are made of plastic, and some of the latest lawn mowers are using them.

Also, the fuel bowl on these plastic carburetors is not as pronounced as the conventional gas bowls in the older models of the lawn mowers.

Where Is The Carburetor Located On A Lawn Mower?

The carburetor of a lawn mower is typically hidden from the view. It is typically present inside or behind an air filter which in some cases has a hood on top. over, the location of the carburetor varies depending on the type of lawn mower and its manufacturer.

However, if you know what you are looking for, finding the carburetor of a lawn mower is not difficult. You can locate the carburetor by simply tracing the air filter or the fuel lines. Here’s a complete guide on how to locate the carburetor of a lawn mower:

Park The Lawn Mower

Park the lawn mower in a comfortable, preferably flat spot so that you do not risk accidentally rolling over the lawn mower. Also, ensure that the ignition is turned off and the engine is cool so that you do not risk burning yourself in the process.

Remove The Engine Hood

As already stated, not all lawn mowers will have engine hoods. It is usually the riding lawn mowers that come with an installed engine hood. So, if your lawn does not have a hood, you can skip this step. The hood is used to protect the engine.

You will have to remove the engine hood to reach the mower’s carburetor. The hood is usually attached to the mower’s body by hood latches. Just release the hood latches on both sides, and you will be able to see all parts of the engine.

Locate The Air Filter

The carburetor of a lawn mower is usually located beneath or behind the air filter. So, you will have to first locate the air filter of your lawn mower, which is often encased in a filter housing.

Depending on the shape of the carburetor, the housing of the air filter can be square or round. The air filter housing is usually located on the side or top of the mower’s engine, and it has slits or holes in it for air intake.

Craftsman Riding Mower Won’t Start Surges Ultrasonic Carburetor Cleaning Repair / Rebuild Model T130

The filter housing is usually attached to the carburetor by screws or fasteners that hold the filter in its place. The filter is usually made up of paper or foam.

The function of the air filter is to prevent dust and lawn debris from entering the carburetor. All in all, finding the filter housing is the key to finding the carburetor of the lawn.

Locate The Gas Tank

Another way of locating the carburetor of a lawn is to trace the gas tank and fuel lines of the mower. For most lawn mowers, locating the gas tank is an easy task.

It is the place where you add gasoline. However, there are some lawn mowers on the market that, just like cars, have the filling cap and gas tank in a different location.

Some lawn mowers also have their gas tank covered. Nonetheless, a gas tank is very easy to locate due to its characteristic shape.

If you can locate the filling cap, you can quickly locate the gas tank by tracing a fuel line to it. From there, it would be straightforward to locate the carburetor of your lawn mower.

The carburetor is usually located next to the fuel tank at some height below it.

Pinpoint The Mower Carburetor

Once you have located both the air filter and the gas tank of your lawn mower, locating the carburetor is easy.

A carburetor is a metal object underneath, beneath, or behind the air filter with springs and levers. These springs and levers regulate the flow of air and fuel into the carburetor for efficient combustion.

If you look closely, you can clearly see that the carburetor has two large holes in it. One of these holes is from where the air enters the combustion chamber of the carburetor.

In the combustion chamber, it is mixed with fuel and then ignited. Due to ignition, the temperature rises, air expands, and it is forcibly ejected through the second hole.

Also, the carburetor of a lawn mower is usually black, lies in the center of the main body and has connections with nearly every essential part of the mower.

However, not all lawn mowers have the same-looking carburetor. The size and shape of the carburetor varies greatly with mower types and mower manufacturers, as described below.

Carburetors On Walk-Behind Mowers

Walk-behind mowers usually come in four different variations. Depending on your needs and requirements, one type might work better for you than the others.

Below we have described the different types of walk-behind mowers and their uses. Following that, we will discuss how you can locate the carburetor of a walk-behind mower.

Electric Walk Mower

As apparent by the name, an electric walk mower runs on electricity. It will not have a carburetor as it runs on an electric motor. Such mowers are suitable for small properties.

Self-Propelled Mower

When you have a large lawn or a big area to mow, self-propelled mowers come in handy. Self-propelled mowers come in two variations: 1) Front-wheel drive and 2) Rear wheel drive. Front-wheel drive lawn mowers are suitable for lawns that are even or flat.

Whereas rear-wheel drive lawn mowers are suitable for lawns with a slope or a lawn located on a sidehill. Nonetheless, both lawn mowers are great for mowing large areas.

How To Locate The Carburetor On A Walk-Behind Lawn Mower?

For most walk-behind lawn mowers, you will find the carburetor on one side of the main body. It is located near the base of the lawn mower. Once again, tracing the air filter and fuel lines is the key to locating the carburetor of a lawn mower.

However, if you are having trouble finding the carburetor of your walk-behind lawn mower, we suggest that you look for the round or square filter housing. It is usually located on the side in walk-behind mowers, though sometimes it might be on the top.

The manufacturers usually make it easy to locate and remove the filter housing so that lawn owners can easily swap filters independently. Once you have located the filter housing, you can pop it open to access the lawn mower’s air filter.

There might be a few screws, latches or bolts holding the filter housing above the carburetor in its place. Ensure that you do not lose the screw or bolts when removing the housing.

Carburetors On Riding Mowers

If you have a very large turf or need to mow a very large area such as a sports field turf, walk-behind mowers just do not cut it.

For such situations, you will need a riding lawn mower. It is more powerful than a walk-behind mower, and you can sit on top of the machine while mowing for easy maneuvering and movement.

Like walk-behind lawn mowers, riding lawn mowers also come in multiple variations. We have described different types of riding mowers in the text below.

Make sure that you know which type of riding mower you have so you can refer to the correct part of this article:

Zero Turn Radius Mower

A zero-turn radius mower has a turning radius that is effectively zero. It can literally turn on a dime and is known for its speed and maneuverability.

Lawn Tractor

A lawn tractor mower has its cutting deck located in the middle of the body. They usually have more power than the other types of riding mowers. Therefore, they are very suitable for mowing large expanses of land.

Rear Engine Riding Mower

It is the smallest of all riding mowers. Unlike the lawn tractor, it has its cutting deck located in the front, making moving around much more effortless. However, it is not as powerful as a lawn tractor due to its small size.

How To Locate The Carburetor On A Riding Lawn Mower?

Identifying and locating the carburetor is generally difficult in riding lawn mowers compared to walk-behind lawn mowers.

It is because riding lawn mowers are larger and more complicated. However, just like walk-behind lawn mowers, the carburetor of a riding lawn mower is located near the engine.

So, once again, you will have to locate the filter housing and the fuel lines of your riding lawn mower to reach the carburetor.

To do this, we highly recommend that you use the manual that came along with the mower to avoid any issues.

If you cannot make any sense of the things mentioned in the manual, a quick search on Google or YouTube can find you an article or video that can help you through the process of locating the carburetor on your lawn mower.

If you are still in doubt or do not want to risk opening the lawn mower on your own, you can always hire a professional to look at your lawn mower.

Do I Need To Clean The Carburetor On My Lawn Mower?

Other than regular wear and tear, the carburetor of a lawn mower is also prone to damage from the lawn debris.

Therefore, the carburetor of the lawn mower needs to be kept clean and in good shape. It directly supports the mower engine in its function, and without it, the lawn mower will eventually stop working altogether.

In many cases, when the lawn mower is not working correctly, the issue is nothing more than a clogged or dirty carburetor.

And if you just clean the carburetor of your lawn in such instances, it will start working again. Below is a list of some issues that result as a result of dirty or clogged lawn mower carburetor:

• Engine stalling while you are mowing the grass.
• Black smoke is coming out of the lawn mower’s muffler.
• Difficulty in starting the lawn mower.
• The engine is running turbulently or sputtering during mowing.
• Fuel efficiency decreases over time.
• Mower starting with a jump or shutting down while mowing.
• Engine overheating during the mowing.

If you have any of the issues mentioned above, chances are it is due to a dirty or clogged carburetor. So, you will need to clean it and here is how you can do it:

How To Clean A Carburetor On A Lawn Mower?

The first thing you need to do while cleaning the carburetor of your mower is to remove it from the mower’s main body. And, Please note that the below-mentioned instructions are only meant to be used as a general guideline. Refer to your lawn mower’s manual for the exact process of removing and cleaning the carburetor.

Removing The Carburetor

• Before cleaning the carburetor, it must be entirely removed from the lawn mower.
• Remove the engine cover if it is required.
• Remove the air filter housing and then the filters.
• Turn off the gasoline if possible. If not, make a crimp in the gasoline line.
• Remove the fuel line from the carburetor and be prepared for some spilling.
• If gasoline falls on the mower, clean it with a rag.
• Disconnect the carburetor’s choke and throttle links.
• Remove the carburetor from the mounting nuts with a sliding motion.
• Release the carburetor bowl, if needed, by unthreading the screws.
• This will release the carburetor bowl.
• Finally, remove the float pin to release the fuel float inside the carburetor.

Once you have taken out the carburetor from the main body of your lawn mower, you can move towards cleaning it. Here’s how to do it:

Cleaning The Carburetor

• In order to completely take out the carburetor of your lawn mower, you will probably have to unscrew the nuts and bolts all around it.
• Once you have done that, you will need to remove the gaskets, diaphragm and the metering plate attached to the carburetor.
• To properly clean the carburetor, ensure that the carburetor intake and outlet ports are fully exposed. Then, use a carburetor cleaner spray to clean it thoroughly.
• If there is a carburetor bowl, make sure that you clean it as well.
• If there are any signs of rust on the carburetor, use sandpaper to clean the rust.
• Following that, allow the carburetor to dry in the open air.
• Once the carburetor is dry, put all the parts together and ensure that everything is in its proper place and you have not missed anything.
• Put the carburetor bowl in its place, if needed and use a sliding motion once again to reinstall the carburetor in its original place.
• Tighten up the bolts and nuts holding the carburetor in its place.
• Reattach fuel lines as well as carburetor throttle links and choke.
• Also, clean the air filter and its housing and reinstall it in its place.
• If there is an engine hood, place it back in its place and you are done. Congrats!

How Do You Fix A Lawn Mower Carburetor?

Sometimes the issue with a faulty lawn mower is not a dirty carburetor but a carburetor that needs to be fixed.

So, if your lawn mower is not working even after cleaning the carburetor, there is an issue with the carburetor or any other part of the engine.

If you are sure that the problem is with the carburetor, you have three options to fix it.

• The first option you have is to get a carburetor repair kit. These kits are readily available, and they are inexpensive. For example, you can easily find a mower carburetor repair kit for about 20 or 30 US dollars on amazon.
• If you think that the carburetor on your lawn mower is beyond repair, do not worry. Carburetor replacements are readily available online and in hardware stores. A typical carburetor replacement can cost anywhere between 50 and 100.
• If you do not want to go through the hassle of fixing the carburetor on your own, you can take it to a professional, and they can fix it for you. The cost will vary depending on the work done and labor cost in your area.

Conclusion | Lawn Mower Carburetor

A lawn mower is a necessary piece of equipment when it comes to lawn care. However, what most people do not understand is that you have to properly take care of your lawn mower to keep it going and increase its life.

And keeping the carburetor of your mower clean and in good shape is vital to lawn mower maintenance.

That is why you should at least clean the carburetor on your mower two to three times a year; however, depending on the use, you might need to clean it more often.

Frequently Asked Questions (FAQs)

How do I know if my lawn mower carburetor is bad?

If the lawn mower has trouble starting or starts with a jump, overheats or stops working during the mowing, releases black smoke or increases fuel consumption, there is a big chance that the carburetor on your mower needs to be cleaned or fixed.

Can you use wd40 to clean a carburetor on a mower?

Yes, you can if you do not have the carburetor cleaner spray. However, we highly recommend that you use a specific carburetor cleaner spray.

What causes a lawn mower to start and then die?

If you are facing a situation in which your lawn mower starts and then quickly dies, there is a high chance that its carburetor needs cleaning or some sort of repairs.

Where do you spray carburetor cleaner on a lawn mower?

You need to spray the carburetor cleaner right in the middle of the carburetor. We suggest that you do it in pulses which is a much more effective approach to removing the debris.

How often should a carburetor be cleaned?

In general, you should at least clean the carburetor of your lawn mower at least two to three times a year. However, depending on the use, this frequency might need to increase.

Lawnmower Won’t Start? Do this.

Bad gas or a dirty carburetor are the most common reasons for a lawnmower that starts hard or runs rough.

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A lawnmower that won’t start, especially when taken from storage, is almost always due to one problem: bad gas.

Storing a lawnmower in the fall without adding gasoline stabilizer to the fuel tank can cause the fuel to break down and plug the fuel passages. If fixing that problem doesn’t help, there are a few others that can help fix a lawnmower that won’t start, as we explain here.

How to Fix a Lawnmower That Won’t Start

Replace the Bad Gas

Over time (like the six months your lawnmower sat in your garage over the winter), the lighter hydrocarbons in gas can evaporate. This process creates gums and varnish that dirty the carburetor, plug fuel passages and prevent gas from flowing into the combustion chamber.

The carburetor bowl below formed corrosion and deposits during storage, which can easily plug fuel passages and prevent the engine from starting.

Storing equipment without stabilizing the gas can lead to deposits that foul the carburetor or injectors.

Ethanol-containing gas can absorb water from the atmosphere, which can lead to phase separation, which occurs when ethanol and gas separate, much like oil and water. Ethanol that has absorbed enough moisture and has sat long enough can foul the fuel system and prevent the engine from starting.

No matter how many times you yank the pull cord and pollute the air with your advanced vocabulary, the lawnmower won’t start if it’s trying to run on bad gas.

In extreme cases, evaporation of lighter hydrocarbons can change the gasoline’s composition enough to prevent it from igniting. The gas may be fueling the engine, but it doesn’t matter if it won’t ignite.

Bad Gas in Your Lawnmower? Here’s How to Fix It

If you neglected to add gasoline stabilizer to the fuel prior to storage, empty the tank and replace with fresh gas. If the tank is nearly empty, simply topping off with fresh gas is often enough to get it started.

On some mowers, you can easily remove and empty the fuel tank. Sometimes that’s more trouble than it’s worth. In these cases, use a fluid extraction pump or even a turkey baster to remove the bad gas. You don’t need to remove all of it; but try to get as much out as possible.

Clean the Carburetor

You’ve replaced the fuel, but your lawnmower still won’t start.

Next, try cleaning the carburetor. Remove the air filter and spray carburetor cleaner into the intake. Let it sit for several minutes to help loosen and dissolve varnish and gums.

Remove the air filter and spray carburetor cleaner into the intake. Let it sit a few minutes to loosen deposits.

On some carburetors, you can easily remove the float bowl. If equipped, first remove the small drain plug and drain the gas from the bowl. Remove the float bowl cover and spray the float and narrow fuel passages with carburetor cleaner.

This kind of “quick-and-dirty” carburetor cleaning is usually all it takes to get the gas flowing again and your lawnmower back to cutting grass.

If not, consider removing the carburetor from the engine, disassembling it and giving it a good cleaning. Be forewarned, however: taking apart a carburetor can lead to nothing but frustration for the uninitiated. Take pictures with your phone to aid in reassembly. Note the positions of any linkages or the settings of any mixture screws, if equipped. If you’re at all reluctant, visit the servicing dealer instead.

Consider replacing the carburetor altogether. It’s a fairly simple process on most smaller mowers and it’s often less expensive than taking it to the dealer.

Direct compressed air from the inside of the air filter out to remove debris that may be reducing airflow and preventing the lawnmower from starting.

Clean/Replace the Air Filter

With the air filter removed, now’s the perfect time to clean it.

Tap rigid filters on a workbench or the palm of your hand to dislodge grass clippings, leaves and other debris. Direct compressed air from the inside of the filter out to avoid lodging debris deeper into the media.

Use soap and water to wash foam filters. If it’s been a few years, simply replace the filter; they’re inexpensive and mark the only line of defense against wear-causing debris entering your engine and wearing the cylinder and piston rings.

An incorrectly gapped spark plug can prevent the engine from starting. Set the gap to the specification given in the owner’s manual.

Check the Spark Plug

A dirty or bad spark plug may also be to blame. Remove the plug and inspect condition. A spark plug in a properly running four-stroke engine should last for years and never appear oily or burned. If so, replace it.

Use a spark-plug tester to check for spark. If you don’t have one, clip the spark-plug boot onto the plug, hold the plug against the metal cylinder head and slowly pull the starter cord. You should see a strong, blue spark. It helps to test the plug in a darkened garage. Replace the plug if you don’t see a spark or it appears weak.

While you’re at it, check the spark-plug gap and set it to the factory specifications noted in the lawnmower owner’s manual.

working on a yard machine 21′ 163cc engine 11A.B9A9729 carb clean a redo video on this repair.

If you know the plug is good, but you still don’t have spark, the coil likely has failed and requires replacement.

Did You Hit a Rock or Other Obstacle?

We’ve all killed a lawnmower engine after hitting a rock or big tree root.

If your lawnmower won’t start in this scenario, you probably sheared the flywheel key. It’s a tiny piece of metal that aligns the flywheel correctly to set the proper engine timing. Hitting an immovable obstacle can immediately stop the mower blade (and crankshaft) while the flywheel keeps spinning, shearing the key.

In this case, the engine timing is off and the mower won’t start until you pull the flywheel and replace the key. It’s an easy enough job IF you have a set of gear pullers lying around the garage. If not, rent a set from a parts store (or buy one…there’s never a bad reason to buy a new tool) or visit the dealer.

My Lawnmower Starts But Runs Poorly

If you finally get the lawnmower started, but it runs like a three-legged dog, try cleaning the carburetor with AMSOIL Power Foam. It’s a potent cleaning agent designed to remove performance-robbing carbon, varnish and other gunk from carburetors and engines.

Add Gasoline Stabilizer to Avoid Most of These Problems

Which sounds better? Completing all these steps each year when your lawnmower won’t start? Or pouring a little gasoline stabilizer into your fuel tank?

Simply using a good gasoline stabilizer can help avoid most of the problems with a lawnmower that won’t start.

AMSOIL Gasoline Stabilizer, for example, keeps fuel fresh up to 12 months. It helps prevent the lighter hydrocarbons from evaporating to reduce gum and varnish and keep the fuel flowing. It also contains corrosion inhibitors for additional protection.

I have a five-gallon gas can in my garage from which I fuel two lawnmowers, two chainsaws, two snowblowers, a string trimmer, an ATV and the occasional brush fire. I treat the fuel with Gasoline Stabilizer every time I fill it so I never have to worry about the gas going bad and causing problems.

You can also use AMSOIL Quickshot. It’s designed primarily to clean carburetors and combustion chambers while addressing problems with ethanol. But it also provides short-term gasoline stabilization of up to six months.

Use a Good Motor Oil for Your Lawnmower

Although motor oil has no bearing on whether your lawnmower starts or not (unless you don’t use oil at all and seize the engine), it pays to use a high-quality motor oil in your lawnmower.

This is especially true for professionals or homeowners running expensive zero-turn or riding mowers.

Lawnmower engines are tougher on oil than most people realize. They’re usually air-cooled, which means they run hotter than liquid-cooled automotive engines.

They often run for hours in hot, dirty, wet conditions. Many don’t have an oil filter, further stressing the oil.

In these conditions, motor oils formulated for standard service can break down, leading to harmful deposits and reduced wear protection.

For maximum performance and life, use a motor oil in your lawnmower designed to deliver commercial-grade protection, like AMSOIL Synthetic Small-Engine Oil.

Its long-life formulation has repeatedly demonstrated its ability to safely exceed original equipment manufacturer (OEM) drain intervals in the toughest conditions. It provides an extra measure of protection when equipment goes longer between oil changes than is recommended by the OEM.

This is Why a Lawn Mower Carburetor is Not Getting Fuel

Your lawn mower isn’t running and you’ve come to the conclusion you aren’t getting fuel to the carburetor.

The carburetor regulates the amount of fuel mixed with air to form combustion in the engine. Without fuel, you’re not going to be getting any mowing done until the fuel supply issue is fixed.

A lawn mower carburetor will not get fuel when old gas corrodes fuel components and leaves gummy deposits restricting the fuel system.

A plugged fuel filter; clogged or kinked fuel lines; a faulty fuel pump; a stuck carburetor float and float needle; or a bad gas cap can result in a lawn mower carburetor not getting fuel.

Before working on your lawn mower, make sure you are in a well-ventilated area. Follow all safety precautions outlined in your operator’s manual. Take caution when working around a hot engine.

This post may include affiliate links. Purchases made through these links may provide a commission for us, at no extra cost to you. As an Amazon Associate, we earn from qualifying purchases.

Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

Reasons a Lawn Mower Carburetor Isn’t Getting Fuel

Old Fuel

First, check the fuel in your lawn mower. Running old gasoline in the mower can cause fuel restrictions keeping your mower from getting gas.

Make sure you are running fresh gasoline so, after you fix your fuel flow problem, you don’t develop restrictions from continuing to run old gas.

Most types of gasoline contain ethanol, a corn-based fuel, to make gas more environmentally friendly. Ethanol naturally attracts moisture from the air.

The mixture of ethanol and water will cause sticky deposits to form causing blockages in the fuel system. This mixture can also cause your fuel components to fail prematurely.

Because gas can break down as quickly as 30 days after you buy it, it’s not only important to use the right type of fuel, but it’s also necessary to consume the fuel you purchase in this time frame.

FIX: Use a siphon pump to drain the old fuel from your tank. Collect the fuel in an approved fuel container so you can later recycle it.

Add fresh fuel along with a fuel additive to stabilize the fuel, reduce moisture and clean the fuel system. I use Sea Foam Motor Treatment in my lawn mower. You can read more about the advantages of Sea Foam here.

Plugged Fuel Filter

Dirt in the fuel system can clog the fuel system and damage fuel components.

To strain any dirt, sediment, or other contaminants to keep them from entering the fuel system, a fuel filter is installed. Most lawn mowers use an inline fuel filter. A fuel line attaches to each end of the filter.

If you are running very dirty fuel or if you haven’t changed your fuel filter annually, the fuel filter can become plugged. When this happens, fuel cannot pass through the filter and to your carburetor.

FIX: Replace a plugged air filter. You will find an arrow on the side of the filter. The new filter must be installed with this arrow pointing in the direction of your fuel flow. The arrow should be pointed toward the carburetor and away from the fuel tank.

Clogged Fuel Lines

Gummy deposits left behind from running old fuel can prevent fuel from flowing through the fuel lines. To find a clog in the fuel line, you will need to check each section of the fuel line by stopping and starting your fuel flow to check for good flow from each section of the line.

You can control the fuel flow using the fuel shut-off valve located at the bottom of the gas tank. If your mower doesn’t have a shut-off valve, pinch pliers also work to crimp the fuel line to stop the flow.

FIX: Once you find a section of the line that is clogged, remove the line from your mower. Spray carburetor cleaner into the line to help loosen the clog. Blow out the line with compressed air. Repeat until you dislodge the clog and open the line.

If you are unable to unclog the line or the fuel line is dry and cracked, it’s time to replace your fuel line.

Bad Fuel Pump

Most gas-powered lawn mowers use a vacuum fuel pump when the carburetor sits higher than the fuel tank. This type of pump builds pressure off the crankcase. It moves fuel to the carburetor because fuel won’t run uphill without it.

When the fuel pump cracks or fails to work correctly you will have to replace it. If you don’t see physical cracks or fuel leaking, you must take some troubleshooting steps to isolate the problem to your fuel pump.

FIX: Before you check your fuel pump, check to make sure you are getting fuel to the fuel pump. You may have completed this step already if you checked your fuel lines and filter for blockages, but if you didn’t, you need to start here.

Stop your fuel flow. Remove the fuel line off the inlet port of your fuel pump. Place the line in a container placed lower than the fuel tank and restart your fuel flow.

If you are getting fuel out of the line and into the container, you have confirmed you have flow. If not, you need to find the blockage that may be in your fuel lines or fuel filter.

Once you have confirmed fuel flow to the pump, reattach the fuel line to the inlet port. Remove the fuel line from the carburetor and place it in a container. Check your pump is working correctly by starting your fuel flow and starting your mower.

You should have a steady or pulsating flow of fuel coming out of the fuel line. If you do not, you need to replace your fuel pump.

Stuck Float or Float Needle

The carburetor won’t get fuel when the float or float needle is stuck and won’t allow fuel to flow into the carburetor bowl. The float and float needle are responsible for regulating the amount of fuel in the bowl.

A float and float needle can become stuck and fail to allow gas into the carburetor bowl. You can attempt to temporarily fix this by tapping on the carburetor with a rubber mallet or the rubber end of a hammer to “unstick” the float needle.

This will work for a time or two, however, the carburetor will have to be disassembled, cleaned, and repaired.

FIX: Take your carburetor apart when you find a stuck float or float needle to determine the actual cause of the failure. You may be able to clean the carburetor to keep the float from sticking.

You may also have to rebuild or replace it to get the carburetor to work right. Read the steps to clean your carburetor in this article.

Bad Gas Cap

Air passes through the vent in a lawn mower gas cap. When this vent becomes plugged, the gas tank acts like a vacuum preventing fuel from leaving the fuel tank.

You may be able to determine whether your fuel cap is clogged by starting your mower and allowing it to run with and without a cap.

If the engine runs okay without the fuel cap, but eventually shuts off or begins to run sluggish with the fuel cap in place, you may have a plugged fuel cap.

FIX: You can attempt to clean your fuel cap to unclog the vent. If this doesn’t work, purchase a new gas cap.

Still Having Problems with Your Lawn Mower?

Lawn mower ownership doesn’t come without its frustrations. Own a mower long enough, you are bound to run into many lawn mower problems including starting, smoking, leaking, cutting, and overheating.

For mower troubleshooting, check out my guide Common Lawn Mower Problems: Solved.

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