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Oil Coming Out Of Exhaust Lawn Mower – What To Do

When operating a lawn mower, it’s not uncommon to encounter issues with the engine that affect its performance. One such issue is if you notice oil coming out of the exhaust. This can show severe problems with the engine, and it’s essential to address them promptly to avoid further damage and potentially costly repairs.

Oil coming out of the exhaust can show various issues with the engine, ranging from minor to severe. For example, it could show worn piston rings, which leak oil into the engine’s combustion chamber and ultimately out of the exhaust. Alternatively, it could be because of a blown head gasket, which can cause oil to leak into the lawnmower exhaust system and mix with the hot gases, resulting in blue smoke and a burning smell.

Regardless of the cause, adding the ss oil coming out of the exhaust as soon as possible is vital to avoid further engine damage and potential safety hazards. This may involve inspecting and fixing internal engine components, like piston rings and head gaskets, or addressing issues with the carburetor or air filter. Proper maintenance and regular check-ups can also help prevent this issue from occurring in the first place.

Oil Coming Out Of Exhaust Lawn Mower - What To Do

In our guide, you can learn more about a lawn mower smoking and leaking oil from exhaust as the engine runs. By the end, you’ll better understand why you have oil in the carburetor and lawn mower spraying because of unburned fuel and how you can start fixing internal problems and these internal engine problems causing spots of dead grass. (Read Can I Use 10w40 Instead Of 10w30)

Potential Causes of Oil Coming Out of Your Lawn Mower Exhaust

One of the reasons why oil might be coming out of your lawn mower’s exhaust is because there is too much oil in the engine. This could have happened because of overfilling or a leaky gasket that has allowed oil to seep into areas it should not be. The excess fuel oil can cause pressure build-up, forcing some of it out through the exhaust.

Another possible reason is clogged air filters. Clogged air filters make breathing hard for your engine and could lead to increased pressure within the engine. As with too much oil in the engine, this could result in some of the oil being forced out through the exhaust system.

To avoid these issues, ensure you use clean oil and change it regularly as per manufacturer recommendations. Similarly, replace air filters and clean your spark plug to prevent them from getting clogged with dirt and debris.

Oil Spillage from Incorrectly Tilting the Lawn Mower

If you have recently tilted your lawn mower to one side and noticed oil coming out of the exhaust, there is a high possibility you are burning oil because of incorrect tilting.

This can be an expensive problem if not addressed quickly, as it can damage your lawn mower’s engine and lead to costly repairs or even replacement. If you notice oil coming out of the exhaust after tilting your lawn mower, you must immediately turn off the machine.

Then, let it cool down completely before checking the oil level using a dipstick. If the oil level is low, fill up with fresh oil and tightly secure the oil cap before starting it again. Note: leaking oil will cover any surface and could cause a fire hazard if it sits in the wrong area.

Overfilled Lawn Mower Crank Case

If you have an overfilled crankcase in your lawn mower, this can cause oil to come out of the exhaust, which is messy and also potentially dangerous. Fortunately, it’s an easy fix you can do yourself with a few simple tools and some know-how. The first step is to remove the oil from the crankcase until it’s at the proper level. This may require draining some of the oil or using a suction pump. (Read Can You Mix SAE 30 And 10w30)

Once you’ve removed the excess oil, startup your push mower and let it run for a few minutes to burn off any remaining oil in the muffler and other components. You may notice some smoke coming out of the exhaust during this process, but that’s normal. After running your mower for a few minutes, turn it off and check the oil level to ensure it’s at the right amount.

Be sure to check your owner’s manual for the right amount of oil


Carburetor Imbalance

An imbalanced carburetor can majorly contribute to lawn mower oil coming out of exhaust of your lawn mower. When the carburetor is out of balance, one cylinder receives more fuel than the other, causing an uneven burn and eventually leading to damage to the engine.

This damage can cause oil to seep into the combustion chamber and be emit through the exhaust. Check for a carburetor imbalance by removing and inspecting both spark plugs.

If one spark plug often appears cleaner or less worn than the other, it could show that only one cylinder works appropriately. Adjusting or cleaning the spark plug in the carburetor may help correct this issue, but it’s vital to ensure any underlying engine damage is addressed as well.

If your lawn mower continues emitting oil after adjusting the carburetor or addressing any engine issues, it may be time to seek professional repair or consider replacing your equipment altogether.

Clogged Air Filter

One of the most common reasons why a lawn mower is spitting oil out of its exhaust is because of a dirty air filter. When a clogged foam air filter doesn’t let enough air into the engine to mix with the fuel, causing an excess buildup of oil in the cylinder, the pressure from this buildup can then cause excess oil not to spit out through the exhaust.

To fix this problem, you must clean your lawn mower’s air filter or replace the air filter. If you have a foam air cleaner, you can easily wash a clogged air filter instead replacing a paper air filter several times a year and stop your oil drips.

Cracked Engine Block

If you notice engine oil leaking out of the exhaust of your lawn mower, it may be a sign you have a cracked engine block. A cracked engine block can cause all sorts of problems for your lawn mower, including overheating and poor performance

Another potential cause of a cracked engine block is a damaged exhaust valve. An exhaust valve that is not working correctly can cause hot gases to build up in the combustion chamber, leading to increased pressure and heat to crack the engine block over time.

Consult with an expert technician or repair service specializing in lawn mowers for proper diagnosis and solution of lawn mowers here. (Read When Is It Too Late To Aerate And Overseed)

Briggs and Stratton Exhaust on a Two-Stroke Lawn Mower Blowing Oil

If your Briggs and Stratton two-stroke lawn mower is blowing oil through the exhaust, it can be an alarming situation. Oil coming out of the exhaust can indicate decreased engine performance, which may lead to higher fuel consumption and reduced power output. Sometimes, this issue also shows blown head gaskets.

One reason more oil you have a Briggs and Stratton blowing oil out of the exhaust could a worn-out piston rings or valve seals. These parts help seal off combustion gas and es prevent oil from entering the engine’s crankcase, preventing oil leakage into the muffler or tailpipe.

Worn Valves

Worn valves commonly cause engine oil leaking out of the exhaust on your lawn mower. When the valve guides in your engine become worn, the seals around them can fail, causing oil to leak into the combustion chamber and burn off through the exhaust system.

The result is a noticeable lawn mower smoking blue or gray smoke out of the exhaust pipe.  If you suspect worn valves are causing your leaking oil or smoke from exhaust pipe. In that case, having them inspected by a professional mechanic or small engine repair shop or technician is vital.

damaged piston rings

Damaged Piston Ring

A damaged piston ring is a common cause of a lawn mower spitting oil out of the exhaust pipe on your lawn mower. The piston ring is responsible for sealing the combustion chamber and preventing oil from entering it.

If a piston ring is damaged or worn, it can no longer do its job correctly, leading to excessive oil consumption and smoke coming out of the exhaust pipe. While replacing the faulty part, you should check that oil leaks may have affected other components like gaskets and seals.

Oil Coming Out of Exhaust on a Four-Stroke Lawn Mower

Oil coming out of the exhaust on a four-stroke lawn mower is a sure sign of trouble. It can show decreased engine performance and, if left unchecked, could lead to blown head gaskets.

The cause of the oil leakage must be addressed immediately to the oil leak and prevent further damage to the engine. One possible cause for oil from the exhaust is overfilling oil in the crankcase.

Oil Coming Out of Riding Lawn Mower’s Exhaust

One of the possible reasons why oil is coming out of your riding lawn mower’s exhaust could be because of an engine oil leak around the combustion chamber. Fuel and air mix, ignite and create power in the combustion chamber. A gap or crack in this; engine oil can seep through and burn with the fuel mixture before exiting through the muffler.

Another potential culprit behind oil coming out of your lawn mower’s exhaust could be a faulty head gasket. The head gasket sits between the engine block and cylinder head, preventing coolant from mixing with engine oil or leaking into cylinders.

It’s best to consult a professional mechanic who can diagnose and fix any issues related to your lawn mower’s engine performance and leaking oil issues. (Learn How Long Does Roundup Take To Work Before Rain)

avoid too much oil

How to avoid adding too much oil

If you have a lawn mower producing oil from its exhaust, it’s time to investigate the root cause. One of the most common reasons for this issue is adding too much oil to your lawn mower. If you’re not careful with the amount of oil you pour into your machine, it can lead to several problems, including smoking lawn mower exhaust.

To avoid adding too much oil to lawn mowers, always check your manufacturer’s instructions and guidelines before filling up. You should never exceed their recommended levels, as doing so could damage your engine or other parts. Check the dipstick after filling up your riding mower and ensure you have reached the appropriate level before starting your machine.

Another important tip in avoiding an excess of oil in carburetor, lawn mower changes are regular. Regularly scheduled maintenance will help keep things running smoothly and prevent unnecessary wear and tear on internal components. By following these simple tips, you can keep your lawn mower running smoothly and prevent oil escaping through the lawn mower exhaust system.

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