Flymo electric lawnmower smoking. Lawn Mower Smoking And Leaking Oil – What To Do

Lawn Mower Smoking and Sputtering- How to Fix [DIY Solution]

Have you ever experienced that your mower is smoking black or white? It’s truly an embarrassing situation for all who just started their lawn mowing but stopped due to smoking and sputtering. If you want to fix the problem, you first need to know why the lawn mower is smoking and sputtering.

Smoking and sputtering can occur in a lawn mower due to some possible reasons. It may happen due to incomplete combustion, overfilling the lawn mower with excessive oil, tipping it the wrong way, and inflating the gasket.

Don’t worry; if you find such problems in your lawn machine that can cause smoking and sputtering, you can fix them yourself. Let’s dive into the topic.

Reasons Why You Lawn Mower Smoking and Sputtering

Your lawn mower is misfiring, putting out black smoke? Let’s know the key reasons below.

Overfill With Engine Oil:

Like a car, you shouldn’t overfill your lawnmower with excessive engine oil because it can overheat the engine.

Your engine might get locked up due to excessive engine oil in your lawn mower. In that case, the engine will not run well and cause smoke. It is one of the most common things that you may come across.

Note: You will face the sputtering problem in your lawn mower due to using old or wrong fuel.

Tip: Check the air filter to ensure it isn’t overfilled with oil. You can use the dipstick to check the oil level.

Tip Over the Lawn Mower in the Wrong Way:

Another common reason for lawn mower smoking and sputtering is tip over the lawn mower incorrectly. If you tip the mower the wrong way, the chances are that the oil will leak into the tube and restrict the fuel line.

Or, if the oil moves into the breathing tube, oil can restrict the air filter. Thus the engine can’t run and cause the problem.

Tip: You can replace the faulty tube with a new one or replace the air filter.

Inflated Gasket:

If the gasket gets a little crack, it will start leaking out the oil, clogging the fuel line and restricting the engine’s running. Ultimately, the engine will be overheated and cause smoking.

Tip: You can repair the gasket crack or change the faulty one with a new head gasket.

Incomplete Combustion:

It happens because of incomplete combustion. Generally, sputtering or smoking is caused by two things.

  • The first one is your spark plug either fouling or not working properly. There is no appropriate gapping.
  • The second reason can be the air filter when it is dirty and not working properly. It can cause incomplete combustion.

Basically, the reason why it causes incomplete combustion (when the spark plug or filter is not working properly) is because of the fuel. The fuel is coming through the lawnmower, but it is not properly burning.

Because of the incomplete fuel burning, it blows out black smoke; your lawnmower will run roughly. You may also experience your lawn mower losing power or backfiring etc.

How to Troubleshoot the Lawn Mower Smoking and Sputtering? Easy 2 Methods

To sort out the problem, the first thing that you usually check is to check the air filter. You should ensure that it is clean and clear, and after that, you must check the spark plug.

Inspect if the plug is really black or carbonated. You may need to change the plug or clean it. Also, inspect the gap and ensure that there is an appropriate one on the spot.

Here, I will explain the process of checking and cleaning the air filter and then the Spark plug. So, let’s come to the diagnosis process.

Step 1- Check the Airport

First of all, you should check the airport. It is all nice. Ensure it should be clean enough. Unscrew the screws and tap the box to open the airport.

Step 2- Inspect the Airport

Once you have removed the airport, inspect it thoroughly. Make sure there should be no dust in excessive amounts.

Step 3- Take off the Foam

For proper cleanliness, take out the foam from the filter and check it thoroughly.

You can see old lawn clippings, dust, and everything like that. Such hurdles add to misfiring and incomplete combustion.

It is a non-effective air filter that deteriorates the overall performance. So you need to clean it. Clean it thoroughly and ensure all the debris and grass particles are removed.

Once it is properly cleaned, reinstall it at the previous place. Check the lawnmower; if it is still sputtering or smoking, then the problem is with the spark plug so check for the spark plug.

Method 2: Check and Fix the Lawnmower Spark Plug?

Here I will teach you three simple steps to check clean and then replace the spark plug if needed. It will boost the engine performance.

Things You Will Need:

  • Spark Plug Wrench
  • Hex turning tool
  • Spark plug wire brush
  • Spark plug gapping tool

Step 1- Read the Manual

It will help you to finish your job quickly and perfectly if you read the instruction manual.

Step 2- Check for Spark Plug

First, you must remove the spark plug to check it thoroughly.

Start with removing the spark plug wire. You can grip it and go ahead and pull it straight off of the spark plug.

Then move it out of the way, get a spark plug wrench, and place it over the spark plug until you feel it engaged.

Then install the hex turning tool and loosen the spark plug. You may need to turn it on for a few seconds.

electric, lawnmower, smoking, lawn, mower, leaking

Once it is removed, you can inspect the spark plug. You can see it is dark and covered with carbon. You can restore it after cleaning the carbon. Also, check for the gap.

Step 3- Clean the Spark Plug

Take a soft wire brush; it would protect your spark plug from damage.

While cleaning it with a brush, start from the outside edge of the spark plug and then turn it. You will be able to access the entire surface and also check for the spark plug gap.

That looks fairly good now; check for the spark plug gap. You should use the spark plug gapping tool.

Insert the tool between the open and gap in the spark plug on the smallest end; this is point zero to zero.

Then slide the spark plug up until it stops. Check the measurement; it should be less than zero

Reinstall it, but if needed replacement, go ahead to replace it with a new one.

Step 4- Replace the Spark Plug

Take a brand new Spark plug that should be compatible with your engine brand. Then take a spark plug wrench to remove the older one and install a newer spark plug.

Place the new spark plug at the end of the wrench and carefully turn the spark plug. Turn it until you feel the threat set, and keep it turning slowly until the spark plug stops.

Tighten it some more to ensure correct installation.

Once you have tightened it, finally reattach the spark plug wire.

Switch on the lawnmower to test, hope there will be no sputtering or smoking issue. You have done your job well.

Frequently Asked Questions(FAQs):

What are signs that a lawn mower air filter is bad?

You may notice poor engine performance if there is a problem with the air filter. Common signs include hard starting, random misfire or sputtering, stalling, smoking, and failure of fuel system parts.

What does it mean when my lawn mower smokes grey or blue?

If you notice your lawn mower is smoking blue or grey smoke, it means the problem is with the engine. Your engine is burning the fuel inside the combustion chamber. Maybe there is leakage of valve seals or bad piston rings.

There may be an issue with the combustion chamber. Coolant or water is vaporized in the combustion chamber, producing white smoke.

What happens if my lawnmower is sputtering or smoking?

If your lawnmower smokes, there is no harm except an unpleasant mowing experience. It may cause frequent engine stalling if you do not immediately remove the issue.

Final Verdict

Lawnmower smoking or sputtering is a common issue you can fix in a couple of minutes. Air filters, combustion chamber, spark plugs, fuel quality, and poor wiring can be possible reasons for smoking.

You should immediately identify and fix the issue for a smooth mowing experience. If you find it tough to solve the problem, then please don’t hesitate to take professional help.


Lawn Mower Smoking And Leaking Oil – What To Do?

Have you ever been mowing your lawn and the engine starts smoking, or worse, it leaks oil? This is a common problem with lawn mowers, and fortunately, there are things you can do to fix it. We’ve researched what to do if your lawn mower is smoking and leaking oil, as well as some tips for preventing this from happening in the future.

A lawn mower smoking and leaking oil can be alarming. These are both signs that something is wrong with the engine and, if left unchecked, could lead to costly repairs. The good news is that there are a few things you can do to troubleshoot the problem. Here are a few ways to do it:

  • Turn off the mower
  • Check the oil level
  • See the mower’s air filter
  • Examine the mower’s spark plugs
  • Inspect the mower’s blade
  • Check the gas tank
  • See the angle of your lawnmower

Keep reading to get more tips on how to fix the issue and get your lawn mower back up and running in no time. Check out different ways to prevent smoking and leaking oil from your lawn mower.

Signs Of A Lawn Mower Smoking And Leaking Oil

If your lawn mower starts smoking or leaking oil, it’s definitely time for a tune-up. So, it’s important to take action immediately. Continuing to operate the mower can cause serious damage to the engine and could even lead to a fire.

Some of the most common signs that your mower is smoking and leaking oil include:

  • White or blue smoke coming from the exhaust
  • Oil dripping from the mower onto the ground
  • A burning smell coming from the mower
  • Strange noises coming from the engine

If you notice any of these signs, shut off the mower and allow it to cool down before checking for leaks.

Is It Normal For A Lawn Mower To Smoke And Leak Oil When It’s New?

Some lawn mowers are shipped with oil already in the engine, so it’s not unusual for them to smoke and leak a little when you first start them up. But then, if your mower is leaking a significant amount of oil or smoking excessively, this could be a sign of a problem.

It’s always best to consult your owner’s manual or contact the manufacturer if you’re unsure. In most cases, a little smoke and some slight leaking is nothing to worry about. but it’s always best to err on the side of caution.

What To Do If You Have A Lawn Mower Smoking And Leaking Oil?

If your lawn mower starts smoking and leaking oil, it’s important to take action right away.

Turn Off the Mower

If your lawn mower starts smoking or leaking oil, it’s important to take action immediately. The first thing you should do is turn off the mower and allow it to cool down.

If the smoke is coming from the engine, it’s likely that something is overheating. Allowing the engine to run for even a few more minutes could cause serious damage.

Check the Oil Level

One of the most common issues with a lawn mower is smoking and leaking oil. In most cases, this problem can be fixed by simply checking the oil level. If the oil is too low, add more until it reaches the full line on the dipstick. If the oil is too high, remove some until it is at the correct level.

It’s also important to make sure that you are using the correct type of oil for your lawn mower. Refer to your owner’s manual for specific recommendations.

Finally, be sure to dispose of used oil properly. Many service stations and auto parts stores offer disposal services for a small fee.

See the Mower’s Air Filter

A dirty air filter is one of the most common reasons for a lawn mower to smoke or leak oil. The air filter keeps dirt and debris out of the engine, and over time it can become clogged with grass and dust.

If your lawn mower’s air filter is dirty, it can restrict airflow to the engine, causing the engine to overheat and smoke. Additionally, a dirty air filter can cause oil to leak from the engine.

To clean the air filter, remove it from the mower and wash it with soap and water. Allow the filter to dry completely before replacing it. By keeping the air filter clean, you can help prevent smoking and oil leaks.

Examine the Mower’s Spark Plugs

Inspect the mower’s spark plugs and replace them if they’re worn out. A dirty spark plug can also cause the engine to run hot and may need to be replaced.

Spark plugs can become fouled with oil and debris, which can cause the engine to misfire. You’ll know the plugs are fouled if they’re black and/or wet.

To clean the plugs, remove them from the engine and scrub them with a wire brush. If they’re excessively dirty, you may need to replace them.

Once the plugs are clean, reattach them and try starting the mower. If it still doesn’t start, you may need to take it to a repair shop.

Inspect the Mower’s Blade

A dull or damaged blade can cause the engine to work harder, leading to smoking and oil leaks. In addition, a blade that isn’t properly mounted can also cause these problems.

If the blade is loose, tighten it up using the appropriate wrench. If it’s dull or damaged, you’ll need to replace it.

Once you’ve inspected the blade, start the mower and let it run for a few minutes to see if the problem has been resolved. If not, there are a few other potential causes you can check, such as the air filter or spark plugs.

Check the Gas Tank

The gas can break down and form a varnish-like substance on the inside of the tank. This can cause clogs and restrict the flow of fuel to the engine, leading to reduced performance and increased wear and tear.

To clean out your gas tank, start draining all of the old gas. Next, add a cup of fresh gasoline and swish it around to loosen any build-up.

Finally, drain out the gas and refill the tank with fresh fuel. If you do this regularly, it will help to keep your lawn mower running smoothly for years to come.

See the Angle of Your Lawnmower

If you notice that your lawn mower is leaking oil and smoking, it’s essential to look at the machine’s angle.

The blade should be level with the ground, and the engine should be slightly higher than the blade. If the engine is lower than the blade, it can cause oil to leak into the engine and start smoking.

By taking these simple steps, you can keep your lawn mower running smoothly and prevent potential damage to the engine.

What Are The Consequences Of A Lawn Mower That Smokes And Leaks Oil?

A lawn mower that smokes and leaks oil can have some consequences.

  • First, it can be a fire hazard. The oil can drip onto the hot engine, causing a fire.
  • The smoke can be harmful to your health. Breathed in, it can irritate your lungs and cause respiratory problems.
  • The leaking oil can pollute the environment. It can contaminate soil and water and harm wildlife.
  • Finally, a smoking and leaking lawn mower is unpleasant to use. It emits toxic fumes and makes a mess of your yard.

If you have a smoking and leaking lawn mower, it’s essential to take it to a repair shop as soon as possible. Otherwise, you may put yourself and your surroundings at risk.

Is It Possible To Fix A Lawn Mower That Is Smoking And Leaking Oil By Yourself?

If your lawn mower is smoking and leaking oil, it’s essential to take action quickly to prevent further damage. In many cases, you can fix the problem yourself with a bit of time and effort.

While it may tempt you to fix the problem yourself, it’s important to remember that lawn mowers are complex machines, and attempting repairs can be dangerous. In addition, many lawn mower manufacturers void the warranty if repairs are attempted by anyone other than a licensed technician.

So, the best action is to take your lawn mower to a qualified repair shop. The technician will diagnose the problem and make the necessary repairs. While it may cost you some money upfront, you’ll save time and hassle in the long run.

How Can You Prevent Your Lawn Mower From Smoking And Leaking Oil?

Lawn mower maintenance is vital to keep your machine running properly. Over time, the engine oil breaks down and degrades, causing it to smoke and leak. You can prevent this by regularly changing the oil and using a higher-quality oil.

In addition, check the air filter regularly and clean it as needed. A clogged air filter can cause the engine to run hotter than usual and smoke.

Finally, make sure that you keep the lawn mower’s deck clean. Grass and other debris can build up on the deck and cause the blades to become imbalanced. This can strain the engine, causing it to smoke and leak oil.

By following these simple tips, you can keep your lawn mower running smoothly for years.

Final Thoughts

The lawn mower smoking and leaking oil can be a scary sight. But, don’t worry. there are a few things you can do to troubleshoot the issue and get your machine running like new again. Review the list above, or reach out to professionals for the best options.

To get more tips on keeping your gardening tools, see our posts below:

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.

electric, lawnmower, smoking, lawn, mower, leaking

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.

Smoking Lawn Mower Engine Fix

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.

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 a Lawn Mower Blows White Smoke — Causes Easy Fixes

If you buy something through our posts, we may get a small commission. Read more here.

Once your lawn mower blows white smoke, you’ll immediately think it’s a serious problem, and repair expenses are costly. But did you know you can do the troubleshooting yourself, even without an expert’s help?

In this article, let our experienced engine experts tackle the possible reasons why this issue happens, along with the easy fixes to make your mower properly functioning again.

electric, lawnmower, smoking, lawn, mower, leaking

Cause #1: Tipped-Over Lawn Mowers

One of the common perpetrators of white smoke is tipped-over lawnmowers. Tipping the mower will cause oil to overflow or reach beyond the dipstick level. Observe your mower and check if it was tipped off at a very steep angle.

If stored at an angle of more than 15, it will lead to white smoke coming from your lawn mower. This can also happen by accident, cleaning the chute or emptying the decks.

This causes the oil to move from the crankcase to the cylinder block, causing the lawnmower to produce white smoke and prompt oil leaks.

How to Fix Your Tipped-Over Mower

To fix a tipped-over mower, position it upright, and check the oil in the gas tank or crankcase before running the engine. Let the engine idle until all the smoke is gone.

It may be a simple solution to your lawn mower smoking, but you’ll still experience smokes rummaging, so it’s best to advise your neighbors to avoid any future complaints.

Cause #2: Oil Overfilling the Engine

A general lawnmower has very little space and container for oil, so, commonly, the crankcase gets overfilled now and then. Check the oil level before mowing again to prevent overfilling the gas tank.

Most people assume that a little oil or too much oil is okay, but this cannot be good for most engines. If the oil engine is higher than the splash paddle, the engines won’t work.

It’s also ideal for observing the smell coming from your engine because when the oil starts to smell like gas, it can indicate a broken carburetor. To quicken the process, extract the excess oil immediately, and ensure you clean your carburetor regularly.

How to Fix Engine Oil Overfill

Turn your engine over and gently flip it to spill the oil away. Replace the plug and follow the detailed measures of carburetor cleaning and replacing the worn-out air filter. A normal lawnmower doesn’t need more than 20 ounces of engine oil, so keep this figure in mind.

Use a dipstick to measure the oil level, and observe whether you should drain or pour some of it to avoid overspilling. For more tips, check this guide to know how much oil should you put in your lawn mower.

Cause #3: Piston Rings are Faulty

A failed piston ring is one of the worst reasons your tractor mower is blowing white smoke. If the lawnmower isn’t maintained properly, chances are it will cause failed piston rings and prompt excess oil in the combustion chambers.

Piston rings keep the mower’s engine oil intact, and it gets damaged due to a dirty air filter or dirty engine oils.

How to Fix Faulty Piston Rings

Faulty piston rings are almost an end game. It will require a complete overhaul, and opening the whole engine is necessary.

Damaged rings will also cause damage to the head cylinder and head gasket, so you’ll have to replace them too. Tapping professional help is best to prevent trouble when fixing your rings.

Cause #4: Leaking or Broken Head Gasket

Another serious reason for a lawn mower’s white smoke is faulty head gaskets. Head gasket failure is a little more complicated problem than the aforementioned reasons above. Head gaskets are seals used to keep a fast engine.

You can find it in the area joining the cylinder and the rest of the engine. When your gaskets are damaged, the engine will produce white smoke. Oil leaks and high crankcase pressures are also common due to faulty head gaskets.

How To Fix the Head Gasket’s Leak/Damage

The only possible way to fix a head gasket failure is to replace it because repairing it is not an option. It’s not expensive, so it’s an easy fix.

Step 1: Get a Head Gasket Replacement

Grab a replacement gasket from your local dealer or purchase it online. Make sure you buy the same gasket type because there’s an array, and it’s not a one-size-fits-all type.

Step 2: Detach the Cylinder Head

Pull out the sparkplug wire and detach the bolts that keep the cylinder attached to the engine block.

Step 3: Detach the Gasket

Look for the gasket on the engine block and remove the gasket with a tool. Be careful when removing the gasket pieces to avoid roughing out the smooth surface while scraping the debris.

Step 4: Install the New Gasket

Your new gasket should fit in perfectly with your engine block. Install the new cylinder head before realigning the sparkplug wire.

Check if Your Mower Has an Overhead Valve Engine

Familiarizing yourself with your engine is vital, so check whether it has overhead-valve engines before taking your lawnmower apart.

Engines with overhead valves have valves and cylinders placed above the combustion chamber. Otherwise, the valves are below the combustion chamber.

Cause #5: Oil Spilled on the Fuel Tank (Applicable to 4-Stroke Lawn Mowers)

Never mix oil and mower fuel if you own a 4-stroke lawnmower. Most lawnmower available in the market now comes with a 4-strokes engine, making them more reliable than the traditional 2-stroke ones. It’s also less difficult to maintain, but mixing oil will cause a serious issue.

Once they infuse inside the lawnmower, the oil will start burning, causing smoke while running. It’s also a perpetrator of premature engine wearing.

How to Fix Oil in the Fuel Tank

To fix the oil in the fuel tank and avoid smoke, the only way is to burn off the contaminated gas by letting the mower run and then replacing it with clean and fresh gas. You will experience white smoke coming out from the mower until it’s able to exhaust all the oil burnt.

But if you’re not comfortable with this fix, you can remove the fuel by detaching the fuel tank and filling it out with a new and clean one.

Step 1: Search for the Fuel Line

Look for your mower’s carburetor and search for the fuel line and fuel tank. This part of the engine is what feeds fuel into the engine.

Step 2: Detach the Fuel Line

Undo the clip that connects the fuel line and maintains its hold. Pull the fuel line off, and unplug the connection from the fuel line to the shut-off valve. The shut-off valve stops the fuel flow to the engine.

Step 3: Gather the Spilled Oil/Gas

Once you have removed the fuel line, the fuel will start to pour and collect with a pain to avoid engine oil spillage, which will be more difficult to clean. It’s also a fire hazard, so be careful about spilling oil over the floor.

Step 4: Empty the Carburetor

Please search for the carburetor and drain the fuel coming out from it. The carburetor of lawnmowers is located underneath, containing a tiny nut or screw used to empty the carburetor.

Why is My Lawn Mower Blowing Blue Smoke?

The most important piece of equipment you own to take care of your lawn is your mower. Mowing your grass regularly at the right height and at the right interval will keep it healthy and looking its best. So if you notice your mower smoking, it’s easy to be concerned. Mowers can be expensive to repair or replace. The good news is that usually blue smoke isn’t as bad as it looks. Lawn mower blowing blue smoke?

Let’s identify the problem and tell you what you need to know to fix it.

It Can Happen to Anyone

Sometimes, even if you use your lawn mower with extra care and caution, follow my recommendations for spring lawn mower maintenance, and winterize your mower properly, you might encounter issues.

That may leave you scratching your head and asking, “What could be wrong with my lawnmower?”

It’s important not to blame yourself – these things happen. Look at it as an opportunity to learn, so you can avoid the same issue in the future.

There are many indicators that your lawn mower needs a tune-up or perhaps needs to be retired and replaced. Maybe your mower isn’t starting properly, or you notice a vibration or wobble during use.

But this article focuses on one issue, and that’s what to do when you see blue smoke coming out of your lawn mower. What’s the cause, how do you know for sure, and what should you do to fix it?

What Causes Your Lawn Mower to Blow Blue Smoke?

Seeing your lawn mower blowing blue smoke can be concerning.

This is especially true if it’s something that you haven’t encountered before, or you don’t consider yourself a pro at fixing stuff. The good news is it’s probably a simple, minor issue:

If blue smoke is coming from your lawn mower, it typically means that your machine is burning excess oil. If you wait it out for 10-15 minutes, the blue smoke should soon dissipate. You probably just need to wait until the extra oil burns off.

Often, this is something that you should not worry about, nor does it require any repair service.

However, it is also essential to understand what caused your lawn mower to billow blue smoke so you can take the necessary measures to prevent it from happening again.

Let’s not make this a habit, eh?

Below are some of the common reasons your lawn mower blows blue smoke, and what you can do to make sure it doesn’t keep happening.

Oil Spill on the Engine

Excess oil may spill onto the engine when you change the oil in your mower. Then, when you fire up the mower, the spilled oil will burn on the hot engine and generate smoke.

The simple solution to this is to let the spilled oil burn off, which will take just a few minutes (and a few concerned looks from your nosy neighbors).

The same thing can happen if you’ve overfilled the mower’s oil reservoir.

Checking the Oil Level

To check the oil level, use the dipstick in the reservoir. Just remove the dipstick, which is attached to the bottom of the cap, then wipe it dry with a clean rag. Insert the dipstick back into the reservoir. Remove the dipstick once again and check the oil level against the “fill” line on the stick.

It’s important to do this check when your mower has been sitting still and before starting the motor. Otherwise, you will not get an accurate reading because the oil will have sloshed around.

Electric Lawn Mower motor problems

If the oil level is too high, you can drain the oil by tipping the mower on its side.

Drain a small amount of oil into a safe container, then check the level again with the dipstick. You can repeat the process until the oil reaches the correct level, as seen on the dipstick.

Finally, run the mower to burn off the excess oil. When the smoke clears, your lawn mower is good to go.

Another way to drain oil from the reservoir is by unbolting the sump plug. However, note that not all lawn mowers are built with a sump plug (check your manual to be sure).

If your lawnmower doesn’t have one, you can use an oil extractor pump to drain oil. Oil extractor pumps are available in most mower shops, and you can buy them online as well (here’s one on Amazon).

Mower has been Tipped on its Side

Sometimes, engine oil can make its way to the cylinder if you tip your mower at a 15-degree angle.

This can happen if you tilt the mower when inspecting under the deck or when you’re replacing the blades. Using your lawn mower on a steep slope may also cause the oil to spill.

You can solve this problem by letting the engine run idly to allow the spilled oil to burn off and smoke to clear.

If you tip your lawn mower for cleaning or maintenance, it is also always a good idea to check the owner’s manual to determine the best ways to reduce oil leaks. Most mowers are designed to tip to one side, but not the other, so consult your manual for best results and to avoid oil getting where it isn’t supposed to go.

Usually, you only want to tip walk-behind mowers toward the oil cap. This is how many of these mowers are designed to have the oil drained.

Oil Residue in New Lawn Mowers

Perhaps you’ve recently bought your first lawn mower (or upgraded from an old one), and when you started the engine, it smoked.

Don’t panic. Sometimes, residual oil may be found in brand new lawn mowers. This is usually the reason why your brand new mower is smoking.

Just let your mower run for up to 15 minutes, then the smoke should clear.

The above issues should not be a cause for alarm. However, if after 15 minutes, smoke continues to billow from your new mower, then you might be dealing with a more serious problem.

Returning and exchanging it for another mower may be your best bet.

Bigger Problems Causing Lawn Mower to Blow Blue Smoke

Here are a few problems you should look out for when troubleshooting blue smoke from your mower.

Typically you’ll only see these issues with older mowers.

Damaged Head Gasket

The head gasket is usually in between the cylinder head and the cylinder block of the mower’s engine. Its main purpose is to keep the engine blocked off from oil or other elements.

If your lawn mower has a blown head gasket, the smoke won’t likely disappear even if you try to drain oil from your mower’s reservoir. Since it’s not sealing the cylinder as it should, oil can leak into it. That oil will burn and give off smoke.

If your lawn mower’s head gasket is damaged or cracked, you’ll need to replace it with a new one.

This is a job for a pro, and it can be expensive. Check to see if your mower is under warranty. If not, get a price from a local small engine repair shop – that’s where you’ll probably get the best deal.

Defective Crankcase Breather

The crankcase breather, also known as the PVC valve, traps gases that escape during combustion to relieve pressure and reduce buildup of corrosive material in the lawn mower’s engine.

If it doesn’t work properly, it may cause damage to other parts of your lawn mower. It may also allow pressure to increase, causing blown seals and gaskets which result in oil leaks.

Replacing the crankcase breather is the best solution and it is relatively fast and easy, without need to tear your lawn mower’s engine apart.

Worn Out Piston Rings

The piston rings of a lawn mower seal the combustion chamber, keeping the oil engine from accessing it. Piston rings may get worn out from frequent use or if the mower is poorly controlled. They may also get damaged if your lawn mower’s air filter is dirty and unable to block dust and other debris.

Not replacing the engine oil in your lawn mower frequently may also result in poor lubrication and cause the piston rings to dry and crack.

Unfortunately, there’s no quick and easy fix if your lawn mower’s piston rings are worn out, damaged, or faulty. Your best option may be to have the entire engine replaced, and depending upon your mower’s value, it may be time to go shopping.

Why Your Lawn Mower is Blowing Blue Smoke

Your lawn mower blowing blue smoke is usually caused by an oil spill or leak. If the smoke clears in less than 15 minutes, then the oil spill is small enough not to cause any major damage to your lawn mower.

The tips and information I’ve shared in this article should help most people diagnose their problem, and prevent any reoccurrence.

However, if your lawn mower continues to blow blue smoke after 15 minutes, you might want to call in a professional small engine repair service for help. Alternatively, if your mower is still covered by warranty, then you can have it checked by the manufacturer.

Either option will probably be less expensive than getting a new one. The biggest cost will be time lost while your mower is in the shop, but you can always ask a neighbor to borrow their mower for a week if needed.

| Denial of responsibility | Contacts |RSS | DE | EN | CZ