When lawn mower smokes. Help! My Lawn Mower Smokes White & Dies | Here Is How To Fix It Fast

Help! My Lawn Mower Smokes White Dies | Here Is How To Fix It Fast!

When it comes to maintaining the health and beauty of your lawn, having the appropriate gardening tools at your disposal can make a significant difference. One of such tools is the lawn mower. Lawn mowers deliver professional results when it comes to cutting your grass. In addition, they make it possible for you to cut the grass in a short time, which ensures that you will have more time for other tasks and projects. If your lawn mower white smoke then dies, read this article!

However, just like any machine, lawn mowers sometimes can also malfunction. For instance, it is common for lawn mowers to blow out white smoke before they suddenly stop working. And, when it occurs during the peak mowing season, it can be quite frustrating.

However, do not worry! It might just mean that there was an oil spill on the engine, which is an easy problem to fix. Having said that, in some cases, your lawn mower might also blow out black or blue smoke, indicating different issues.

So, if your lawn mower is blowing smoke and suddenly shutting down, keep reading! We will discuss the causes of white smoke in lawn mowers what you can do to fix it.

White Smoke Is Not Always A Serious Issue!

The emission of a small amount of white smoke from a lawnmower is a common occurrence. However, white smoke from a lawn mower is not always a serious issue. In most cases, this indicates that the gas feed jet has become blocked.

If you have been using a lawn mower for a few years, there is a big chance that you might have encountered this situation at least once. White smoke from your mower may look like a serious problem, but the solution is simple in most cases.

There are a lot of different things that could be causing your lawn mower to blow out white smoke and shut down. Once you completely understand all of these factors, it will be much easier for you to take the necessary measures.

Following are some reasons why a lawn mower will typically emit white smoke:

• Cylinder and/or rings are worn
• Damaged piston rings or cylinder
• Engine overfilled it with oil
• The engine that has completely worn out
• Moisture build-up in the tank
• Mower tipped over incorrectly
• The breather tube is obstructed
• There is an air leak in the crankcase
• Using oil grades that are not suitable

Fortunately, in most cases, figuring out and resolving issues of this nature does not require a specialist’s assistance. For further information, check the manual that came with your lawn mower. If you don’t have the manual itself, you can typically find it and download it from the manufacturer’s website by searching the name and model number of your mower plus the word “manual.”

Troubleshooting A Lawn Mower For White Smoke

Before we move on towards discussing the causes of white smoke in lawn mowers, let’s just quickly go over a quick troubleshooting guide. It will help you pinpoint the exact reason behind a malfunctioning lawn mower and save you a lot of time.

• Check the air filter first, and change it if it’s unclean.
• Check the oil level next. Then, if necessary, fill with the right grade of oil.
• Mowing at steep angles for an extended time can also result in smoke due to oil leaks. So, make sure caps are fully tightened.
• To burn out any oil that could have gotten into the engine, start the mower and let it run for 10 to 15 minutes.

Now, let’s move on to have a more in-depth conversation about each of the issues. I will also describe the steps and measures that need to be taken in order to solve such problems and avoid them from occurring in the future.

Moisture Build-Up in the Tank

When it comes to the lawn mower, it is not a good sign that there is water in either the fuel line or the fuel tank. It always has the potential to cause engine problems. When the water has invaded the cylinder, it won’t be easy to light the cylinder. Additionally, it prevents the fuel from being ignited in the correct manner. In most cases, an excessive amount of condensation is the source of the water.

You can place the responsibility for this on the environmental factors. But, there are also times when a wobbly gas cap could cause it. You must empty the tank and fill it with new, untainted fuel to get rid of the water. And, it goes without saying that you must remember to get rid of the gas and oil you removed from the tank earlier in the process.

Engine Overfilled It With Oil

Even though you may believe that excess oil will simply be burned off, excessive oil can cause serious damage to the engine of your lawn mower. This is because the vast majority of engines use splash lubrication systems. Therefore, if you use an excessive amount of oil, the level of the oil will end up being higher than the splash paddle.

When this occurs, you will have issues such as white smoke. Putting in an excessive amount of oil is one of the most common reasons for white smoke, so when changing the oil in your mower, make sure that you only put in the required amount. It’s a waste of resources and won’t do your machine any good.

The solution is to let the engine cruise at a low speed while you drain the excess oil and wait for the smoke to clear. This could take up to five minutes of your time. Read the owner’s manual of your mower on a semi-regular basis to refresh how much engine oil you need to put in your lawn mower. In most circumstances, the engine oil requirement for your lawnmower should not exceed 20 ounces.

However, make sure that you use the exact quantity. After the engine has been lubricated with oil, use a dipstick to find out the level of oil in the engine and ensure that it is within the recommended range. If there is any indication of an overfill, remove any excess oil.

Lawn Mower Tipped Over

Is the angle at which your lawn mower is tipped greater than 15 degrees when you mow your lawn? Maybe it is possible that you stored it in that manner or that you accidentally tipped it over. However, the vast majority of people get themselves into this situation when they are cleaning under the deck or even when they are emptying the chute.

With any lawn mower, you should avoid mowing on any surface with a slope of more than 15 degrees unless the mower is specifically designed to cut on steep heels. In addition, if performing maintenance on the mower requires you to tip it over, you should do so with the carburetor, and air filter positioned so that they are facing upwards.

Nevertheless, when people accidentally topple their mower, the oil moves from the crankcase to the cylinder, and your lawnmower begins to smoke as soon as you start cutting again. In certain instances, the oil will leak as well. The easiest way to fix this issue is to let the engine keep running until all of the oil that has made its way into the cylinder has been burnt. It is also important that you consult the user manual of your mower.

It will tell you exactly how to overturn the mower for cleaning and repairs and whether it is possible to use a particular mower on a steep area.

Head Gasket Failure

pxhere Head gasket failure leads to a malfunctioning engine which causes the production of white smoke.

It is much less likely that the head gasket will fail, but if it does, it will produce a lot of smoke. In contrast to the problems discussed previously, this one requires slightly more effort. A head gasket is made of metal and graphite.

In an engine, it is installed in the space between the cylinder head and cylinder block. It is responsible for preventing leaks in the combustion chamber. If the head gasket fails, you may experience other symptoms, such as an odd noise, oil leaks, increased pressure within the crankcase, and smoke.

Head gasket failure leads to a malfunctioning engine seal, and some pressure will inevitably be lost from the cylinder. In addition, even a very small hole in the head gasket can allow the oil to seep into the cylinder that separates the combustion chamber and the engine. The solution is to get a new head gasket installed.

However, if you discover that you have worn piston rings or rings that have failed, you will most likely need a new engine. A brand-new engine is almost always the more affordable option and comes with a warranty.

Gas In The Oil

If your lawn mower is emitting white smoke, you may have mistakenly put oil into the gas tank. Unfortunately, this is a problem that arises quite frequently. If you made this mistake and need to fix it, empty the gas tank and fill it with fresh gas. If you want things to go more smoothly, you can use a siphon or a fluid extractor.

However, you should not start the engine if the oil has a smell similar to that of gas. This indicates that the seal on your carburetor has been broken. In this particular scenario, you should first make the necessary adjustments to the carburetor and swap out the machine’s oil before attempting to use it again.

If you try to run the engine without adding the appropriate amount of oil or fixing the problem, you could end up causing damage to the engine since the oil will be too thin because of the mixed fuel. After removing the contaminated fuel, continue operating the mower’s engine until it stops working due to the lack of fuel.

This ought to clean the gas out of the system so you can put in new gas. If the engine will not start despite your best efforts, the carburetor most likely needs to be cleaned.

Damaged Piston Rings

Several different factors can lead to the piston rings becoming damaged. However, the worn-out or dirty air filter is the most common cause of this problem. This problem is pretty much unavoidable if you don’t perform proper and regular maintenance on your mower. Due to dirty air or worn-out air filters, dust and other minute particles can enter the combustion chamber, which could cause severe damage to the piston rings.

Since piston rings regulate the amount of engine oil and drain any surplus oil from the combustion chamber, if you have damaged piston rings, it will not be possible to prevent oil from getting into the combustion chamber. Having bad piston rings is bad news because you cannot fix them unless you are a professional.

And damaged piston rings indicate a cylinder problem as well. So, it becomes necessary to completely rebuild the engine in order to repair the piston rings. However, if you’re determined to fix it, take it to a professional repair shop.

Mower White Smoke

Nonetheless, purchasing an entirely new engine would be the most sensible choice in such a situation where piston rings have been damaged.

Final Thoughts

Remember that brand-new lawn mowers tend to produce white smoke for a short time until they get going and adjust to everything. So don’t freak out if you see this on the first mow you make with your brand-new mower; it’s perfectly normal.

However, on the other hand, if you see white smoke coming from an old lawn mower before it shuts down, the most likely causes are what I mentioned above. The appearance of white smoke is often alarming, but the problem can often be easily resolved with little effort. Blue or black smoke is much more hazardous to your lawnmower than white smoke.

With white smoke, it’s simply a matter of resolving a minor issue and running the engine until the smoke disappears. However, if you cannot determine the problem, consult an expert.

Frequently Asked Questions

Can you run a lawnmower with a blown head gasket?

Your lawn mower will not be able to operate at full power if the seals on the head gasket or the head of the gasket have blown out. In addition, a blown head gasket can be quite pricey to fix if it is not replaced on time. So, you should get it fixed as quickly as you can.

How do I know if my lawn mower has a blown head gasket?

You have a bad gasket if the mower is stalling out or won’t start when you know of the oil leak. Also, if the mower cuts out when you turn a corner, but there is no oil leak, the gasket may still be damaged because there is insufficient pressure to maintain combustion.

What does it mean when a lawn mower blows white smoke?

White smoke is often caused by a blown head gasket, incorrect oil grades, air leaks or worn piston rings and cylinders. However, a tilted engine is the most common reason for white smoke blowing out of your lawnmower. No lawnmower should be tilted at an angle greater than 15 unless it is specifically designed to do so.

Will too much oil cause white smoke?

Yes! White smoke can be caused by too much oil. However, the oil getting into the combustion chamber is the issue here, not the oil itself. When oil levels are excessively high, it spills into the combustion chamber and burns with the fuel and air, emitting smoke.

Why does my lawn mower die after running for a few seconds?

Your lawn mower may be unable to keep running if the spark plug is damaged or unclean. If the plug is clogged with dirt and grease, the mower may be able to produce the initial spark. However, the spark won’t be sufficient to keep the engine going.

Lawnmower Smokes on Startup – This is why…

A smoking mower is a pain, not to mention bad for your health and the environment. Fixing the issue is usually a simple fix. I’m a mechanic, and you’ll learn a few tricks to take care of the problem the easy way.

A lawnmower engine commonly smokes on startup because the oil level is over full. Other common causes include:

In this post, you’ll learn to diagnose why your mower smokes on startup and what you can do to fix it right now!

We’ll begin with the most common reasons first.

Engine Oil Level Over Full

Engine oil is super important for the performance and the health of your mower engine. A low oil level will cause some irreparable damage and is a common engine killer.

Of course, most folks know that and top up their mower oil level regularly. The thing is, in my experience, they very often overfill the oil level.

Over-full oil is bad for two reasons:

1 – The excess oil makes its way inside the combustion chamber and burns to cause smoke.

2 – An over-full oil level is bad for a small engine because most small engines commonly employ splash lubrication, and overfilling such a system actually prevents proper oil lubrication.

How to diagnose: Easy, check your engine oil level. See the infographic below.

How to fix it: If you find your oil level is too full, to fix it, we’ll need to remove some. I use an oil siphon to remove the excess oil; it’s the fastest and cleanest option.

That said, you can drain some oil by following your mower’s oil drain procedure. Older mowers usually have an oil drain bung on the bottom of the engine. modern engines drain the oil through the dipstick, you’ll need a shallow container, and you’ll need to tilt your mower over. It’s covered in the video below.

If you haven’t changed your oil this season, it makes sense to drain it all out and replace it with fresh oil. I’ve covered the whole procedure here in “Mower tune-up.”

Mower Stored Incorrectly

While some mowers may be stored ergonomically by folding their handlebars flat and storing them by tilting them upwards, you’ll find those types of mowers have an engine designed especially for that purpose.

Storing a regular mower in that way or indeed even tilting a mower over on its side to clean the deck after use may cause engine oil to sneak into the combustion chamber, which burns off the next time you start the engine-causing engine smoke.

If you have been storing your mower in this way or tilting your mower over in this way, it’s very likely this is the cause of the smoke on startup.

The fix – It’s safe to tilt your mower over to store it, check the blade, clean the deck, etc., but you’ll need to tilt it carburetor side upwards.

Doing so helps prevent oil from entering the engine and also gas spills. Check out the video below.

Wrong Oil Type

Oil is oil, right? Well….yes and no. Oil is, as you know, graded by weight; broadly, weight refers to how thick the oil is. And while most engines will be pretty happy with a regular engine oil grade, they may not like light oil.

Such high-performance grade oils are designed for higher-performing engines with tighter tolerances. Using them in a mower engine with wider tolerances allows the oil to slip past sealing surfaces and into the combustion chamber, which, as you know, is where it’s burnt and results in smoke.

All engines will have a preferred oil type which engine manufacturers have tested and so should ideally be followed.

Failing to use the correct oil type and quantity may void your engine warranty.

How to fix: If you think this may be your problem, go ahead and drain your oil and replace it with the correct oil type; check the infographic below for the recommended oil type. Job Done!

Worn Valve Stem Seals

What are valve seals? Valves, as you know, are mechanical components that open and close sequentially to allow your engine to breathe. As they are moving parts, they obviously need lubrication.

Therein presents a problem, while the valve opens a passageway to the combustion chamber, its shaft must be lubricated. Oil from the shaft could easily enter the combustion chamber if not for the valve stem seal.

The seal, as its name suggests, slips over the shaft and prevents oil from entering the combustion chamber.

So what’s the problem with the seals? There are a couple of common problems, the most common of which is hard seals.

Hard Seals – The seals simply get hard with age or where the engine oil isn’t changed regularly. When they get hard, they allow oil to sneak past.

Replacing the seals is the more usual repair. It’s not a difficult job but does require an engine partial strip.

Before going that road, it may be worth trying a seal conditioner. It’s an oil additive that will help if your seals are simply hard. However, it won’t solve a worn or damaged seal issue; they’ll need to be replaced.

Here’s a link to the treatment I’ve been using for years; it’s called Lucas oil treatment, and it’s sold and delivered by Amazon.com.

Worn seals – General wear and tear of seals is generally caused by wear in the valve sleeve itself. The greater movement in the valve stem causes the valve seal to widen, allowing oil to slip past.

The only fix here is to replace the seals.

How to replace Valve Stem Seals

To replace the valve stem seals, we’ll need to remove the valve cover, valve rockers, push rods, valve keepers, valve cap, and spring.

But before we do any of that, we’ll need to prevent the valves from falling into the cylinder when the valve keepers are removed.

Here’s a handy mechanics secret – Remove the spark plug and stuff a soft rope into the cylinder, not forgetting to keep hold of one end.

• Now go ahead and rotate the crankshaft clockwise so as to squash the rope into the combustion chamber. The rope pushing on the valves keeps them in place when the keepers are removed.
• Now you are free to remove the valve rockers, pushrod, keepers, cap, and spring.
• Remove the seals by prying them upwards and sliding them off the valve stem.
• Fit the new seals

Reverse the process to rebuild.

Note valve lash will need to be adjusted, and I’ve covered that in a post previously – “Adjusting Valve Lash,” or you can check out the video below.

You may also find these pages helpful:

John Cunningham is an Automotive Technician and writer at Lawnmowerfixed.com.

He’s been a mechanic for over twenty-five years and shares his know-how and hands-on experience in our DIY repair guides.

Johns’s fluff-free How-to guides help homeowners fix lawnmowers, tractor mowers, chainsaws, leaf blowers, power washers, generators, snow blowers, and more.

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.

And the best part. it’s free!

The Many Reasons Why Lawnmowers Can Blow Smoke

In good working order, a lawnmower controls the power of combustion to provide a fantastic tool for conquering grass. In fact, I don’t need to convince anyone of its usefulness —a lawnmower is a mainstay in any garage.

However, when small engines aren’t working correctly, they really let you know about it. If you’re like me, you’re well-acquainted with the plumes of smoke emitted from 4-cycle engines.

But what do those plumes of smoke mean?

We’ll go through each and help you troubleshoot what’s going wrong with your lawnmower. Without further ado, here are the main reasons why lawnmowers blow different types of smoke.

First, we’re going to explore why lawnmowers can blow out black smoke. You might think it’s similar to our guide on patio heaters blowing black smoke, but unfortunately things are a bit more complicated than that.

Black Lawnmower Smoke

There are three main reasons why your lawnmower could be blowing out black smoke.

• The gasoline to air ratio is too rich. This indicates too much gasoline is pumped into the cylinders.
• Oil has been incorrectly dispensed into the cylinders and is being burnt as fuel.
• The air filter is not working properly, causing dust or other debris to be combusted.

As an astute reader, you’re probably wondering which of these issues is causing your black smoke problem. To verify which issue you’re experiencing, here is what we’ll need to determine.

Verify whether your choke is open

Unless your lawnmower has a fuel injector, it probably has a choke.

The choke restricts the airflow to the carburetor, which in turn mixes the air and fuel before passing the mixture to the engine. It’s primarily useful as a way to get the engine running from rest, when the energy demands are much higher.

With the choke closed, the mixture has a denser concentration of gasoline. This increases the amount of energy that the engine has to capture and can cause rattling, noise, and black smoke.

If your lawnmower runs fine otherwise, double check that your choke is open. This may be the only thing necessary to solve your black smoke issue!

Check your air filter for damage or clogs

So, your choke is open but your lawnmower is still blowing black smoke?

The next thing to check is the air filter — it may have unseen damage or clogs. Follow your manufacturer’s guide on how to replace your air filter. Here’s an example for Briggs Stratton engines.

If there are clogs, the reduced airflow can cause the same problem that we examined above with closed chokes. The mixture of fuel / air reaching the engine contains too much fuel and not enough air.

If there aren’t clogs or obvious damage, the problem most likely lies in the carburetor itself.

Check your carburetor

If you’ve made it this far, prepare to get your hands dirty or hire some outside help to assist you. However, I would encourage you to try to diagnose the issue yourself before taking the mower to a small engine specialist.

With that being said, the first thing you can try is to adjust your carburetor.

There are usually two adjustment screws on top of the carburetor. One of these screws controls the RPM speed at idle and the other will tweak the ratio of air to fuel.

HOW-TO fix a smoking craftsman tractor under 12 | lawn tractor white smoke oil leak fix

In addition to watching the video above, try to find your mower’s user manual and locate a diagram for which screw is which. This will potentially save you a headache later on.

If adjustments don’t work, you can also try cleaning your carburetor.

This is typically a solution for mowers not starting at all, but it’s not unheard of to have gunk impeding airflow from the intake (again causing the fuel mixture to skew toward having more gasoline).

Blue / White Lawnmower Smoke

Unlike black smoke, blue and white lawnmower smoke typically means one thing: you’re burning oil. The only question to answer next is why your lawnmower is burning oil.

There are many possibilities for why this happened. In no particular order, here they are.

• You might have used oil not rated properly for your engine.
• At some point, you may have blown your head gasket.
• Your O-rings / cylinder degraded and are leaking. This often accompanies leaking oil.
• The engine ran at greater than a 15 degree angle, causing oil to move into areas it shouldn’t be.
• You turned your mower upside down (even briefly) to work on it or sharpen the blades.
• You have overfilled the crankcase with oil.
• The crankcase breather is non-functional.

So, with so many different possibilities, how do you confidently diagnose the problem?

First things first — check and/or replace your engine oil. This is an easy bit of maintenance that removes a few different possibilities at once. Not to mention, it’s probably something you’ve been meaning to do for a while anyway!

Changing the engine oil first will ensure that you’ve drained all of the existing oil, that you’ve replaced it with properly graded oil, and that the crankcase has not been overfilled.

If you’ve never changed your lawnmower’s oil before, check out this wonderful YouTube video.

Is your engine still smoking? If so, check to see if you’ve blown a head gasket.

At this point, you’ve ran through everything I know to try to diagnose. If the problem persists, consider taking your mower into the shop and have a licensed small engine repairperson take a look.

Alternatively, you could purchase a new model (although I’m of the mindset that you should always try to repair first).

White Lawnmower Smoke

There’s one thing not mentioned above that is unique to engines that are blowing white smoke.

Condensation can often build in the engine’s exhaust on damp mornings. As the engine runs, the heat will turn this condensation into simple run-of-the-mill steam.

If this is the case, running the mower for a while should completely fix the issue.

However, I wouldn’t start with this assumption. Running a small engine with any of the problems mentioned above can cause damage to the engine (and be dangerous for bystanders).

Electric Lawnmower Smoke

If your electric lawnmower is smoking, this indicates that something is majorly wrong! Most typically, the motor itself burned out and needs to be replaced/discarded.

However, more rare (and more severe), there is a problem with the battery. This can release a lot of energy quickly and should be taken very seriously.

Because of the possibility for a battery explosion, you should immediately do the following:

• If the lawnmower is still plugged into the wall, unplug it (if safe).
• Grab a fire extinguisher and douse the machine with the extinguisher’s contents. Be sure to get it inside the vents.
• Move the electric lawnmower away from anything flammable, preferably to an open-air space.

One final thing to note — it’s also possible that the electric motor belt has simply gotten too hot. If you’re mowing particularly thick grass, this can happen.

Safety First

I hope it goes without saying, but — often where there’s smoke, there’s fire.

Because of this, take care when diagnosing your issues and make sure you follow proper safety precautions.

Our guide on gas generator safety is a decent place to start. However, if you don’t want to read that, at least have a fire extinguisher ready (at a minimum).

Additionally, don’t be afraid to call the fire department if it ever looks like things are going to get out of your control. You don’t want to cause damage to person or property because you’re too proud to call for help!

Posted on Last updated: August 8, 2020

Why Is My Lawn Mower Blowing White Smoke?

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Getting a big Cloud of white smoke can be scary. Most people don’t expect it to happen — but why is it even happening?

Why is your lawn mower blowing white smoke? The truth is, it could be one of these reasons:

• An air leak in your crankcase
• An overfilled crankcase
• A broken or not working breather in your crankcase
• Poor grades of oil
• If you tilted the engine for more than 15 degrees (even if just for storage)
• If your cylinder is worn out
• Head gasket broke

Of course, just knowing what caused your lawnmower to blow white smoke is not enough — you also have to know how to fix it. So, if you want to learn more about these issues (as well as

some other problems that may be the cause of white smoke), as well as the solutions, read on.

Common Reasons a Lawn Mower Is Blowing White Smoke

As mentioned, there are some common reasons why your lawn mower may be blowing white smoke. It happens often — much more often than you’d think — and most of these problems are easy to troubleshoot, but more on that later.

For now, let’s just take a look at all of the possible reasons why your lawn mower may be blowing white smoke. Some of them you’ve already seen at the beginning of this article. Here they are:

• Tilted engine, as the most common reason for white smoke blowing out of your lawnmower (no lawnmower should be tilted at an angle bigger than 15 degrees).
• Oil issues such as overflowing oil or wrong type of the oil are the second most common cause, and it’s often very easy to fix.
• Leaks are another common issue, and they could cause even more problems if you leave them be.
• Broken parts such as the head gasket, cylinders, etc. need to be checked for once in a while to prevent these issues.

Other than these causes, there are some less common ones, but it’s good to be aware of them, just in case you are one of the people it happens to. Here they are:

• Blocking of the breather
• Putting more oil than the dipstick shows
• Damaged piston rings

Fortunately, all of these are easy enough to repair. There’s no room for panic. First, you need to shut your machine off and let it cool down. Then, you can move on to some solutions.

How to Fix the Most Common Causes of White Smoke in Lawn Mowers

While white smoke looks scary and like a serious issue, it’s actually not. You can fix it in no time if you just follow some simple steps. Naturally, you may not know immediately what caused the smoke, but it doesn’t hurt to test some of these solutions out until you get it right.

Cause #1: Lawn Mower Tipped Over

Starting with the most basic cause of white smoke in lawn mowers, this one is also the easiest to fix. You’ll also know if this is the cause right away. Has your lawn mower been tipped at an angle greater than 15 degrees? Maybe you stored it that way, or you accidentally moved it like that.

Most people end up with this issue because of cleaning under the deck or even because they are emptying the chute. When they do this, the oil moves from the crankcase to the cylinder, and once you start mowing again, your lawnmower starts to smoke.

In some cases, the oil will leak too.

The best solution for this is to put the lawnmower upright, check the oil in the crankcase (add more if necessary), and then let the engine run until the smoke dissipates. It’s a simple solution, although it may not be comfortable for your neighbors because of all the smoke.

But if you have a tractor mower, this will usually not be the case, so you have to look for other causes.

Copyright protected content owner: ReadyToDIY.com and was initially posted on 2020-05-25.

Cause #2: Oil Issues

In general, your lawnmower will take a little over a pound (near 0.5 l) of oil. This is a really small amount, so it would be no wonder if you overfilled the crankcase once in a while. It’s common. To prevent it, just check the level and the amount carefully before moving on to mowing.

Often, people think that a little oil can’t hurt anyone, especially not the lawnmower, but the fact is that it could be very bad for their engine. Most engines work on a system of splash lubrication, and if the oil level is higher than the paddles, it won’t work well.

In this case, the engine is blowing white smoke because it’s trying to burn all of that oil. You can fix it quickly by draining the oil and then let the engine run until the smoke is no longer present. It’s a quick and simple solution, just like with the first cause of white smoke.

While extracting the excess oil could be bothersome, especially on some models, you should do your best because it will make the process quicker.

If the oil smells like gas, you shouldn’t run the engine, though. This will mean that your carburetor seal is broken. In this case, you want to make the fix to the carburetor and then change the oil before using the machine again.

If you try to run the engine without adding proper oil and fixing the problem, you could damage the engine because the oil will be too thin (because of the gas).

Another thing that could happen is that the oil has found the way to the carburetor, and then the gas can’t get to the jet. If you run the engine a few times, you will be able to spend that oil, and the smoke will go away. If it seems like it won’t work, you should clean your carburetor.

For one, you’ll have to turn your engine over and then spill the oil from it. Then, you can replace the plug and try again. There are more detailed cleaning measures for the carburetor, but try them after you try this first as it’s simple, and it might just solve your issue.

You could also put oil in the gas tank by accident, which is a common mistake. To fix it, just drain the oil and put in the gas. Run the engine for a while afterward, so the remaining oil clears out, and the smoke goes away. Again, you could clean the entire carburetor.

Cause #3: Head Gasket Issues

If your head gasket breaks, you’ll probably see a lot of smoke. It’s less common too, but it’s still possible — harder to fix, too.

Copyright article owner is ReadyToDIY.com for this article. This post was first published on 2020-05-25.

A head gasket is a part lodged in between the cylinder head in an engine and the cylinder block, and it serves the purpose of sealing the area where the combustion happens. Some common symptoms — other than white smoke — of this problem are oil leaks, more pressure in the crankcase, a strange noise, etc.

To fix it, you have to replace it.

Final Thoughts

White smoke tends to be concerning, but it’s usually an easy fix. Far more dangerous for your lawnmower is blue or black smoke. With white smoke, it’s just a matter of fixing a simple issue and letting the engine run until the smoke is no longer there.

Keep in mind that new lawnmowers tend to blow white smoke for a while until they get started and adapt to everything. So, don’t get alarmed if you see this on your first mowing round with your new mower.

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ReadyToDIY is the owner of this article. This post was published on 2020-05-25.