Seeing oil coming out of the exhaust of your lawn mower can be concerning. Not only is it a sign that something is wrong, but it can also indicate a potential problem that can lead to more serious damage to your mower. Here are some possible reasons why oil is coming out of your lawn mower’s exhaust and what you can do to fix it.

Oil coming out of exhaust on lawn mower

1. Overfilled oil: One of the most common reasons for oil coming out of the exhaust is overfilled oil. If you recently added oil to your lawn mower and didn’t check the oil level, you may have added too much. As the engine runs, the excess oil can get pushed into the exhaust, resulting in a visible smoke coming out of the exhaust.

Solution: Check the oil level and drain the excess oil if necessary.

2. Worn piston rings: Piston rings are responsible for sealing the combustion chamber, preventing oil from leaking into the combustion chamber. If the piston rings are worn, the oil can leak past them and into the combustion chamber, resulting in visible smoke coming out of the exhaust.

Solution: Replace the worn piston rings.

3. Blown head gasket: The head gasket is responsible for sealing the engine block and cylinder head, preventing oil from leaking into the combustion chamber. If the head gasket is blown, oil can leak into the combustion chamber, resulting in visible smoke coming out of the exhaust.

Solution: Replace the blown head gasket.

4. Worn valve guides or seals: The valve guides and seals are responsible for guiding the valves and preventing oil from entering the combustion chamber. If the valve guides or seals are worn, oil can leak past them and into the combustion chamber, resulting in visible smoke coming out of the exhaust.

Solution: Replace the worn valve guides or seals.

5. Clogged breather: The breather is responsible for allowing the engine to breathe, preventing pressure buildup in the crankcase. If the breather is clogged, pressure can build up in the crankcase, pushing oil into the combustion chamber and resulting in visible smoke coming out of the exhaust.

Solution: Clean or replace the clogged breather.

Why is my lawn mower spitting out oil and white smoke?

If your lawn mower is spitting out oil and white smoke, there are a few possible reasons:

1. Overfilled oil: If the oil level in the lawn mower is too high, it can cause oil to leak out of the exhaust and result in white smoke. Check the oil level and drain some if necessary.
2. Worn piston rings: The piston rings are responsible for sealing the combustion chamber and preventing oil from entering it. If they are worn, oil can leak into the combustion chamber and burn with the fuel, causing white smoke. This is a more serious issue that requires engine repair or replacement.
3. Clogged breather tube: The breather tube allows air to flow in and out of the engine, and if it becomes clogged, pressure can build up in the engine and cause oil to leak out of the exhaust. Clean or replace the breather tube as needed.
4. Blown head gasket: The head gasket is responsible for sealing the cylinder head to the engine block. If it blows, oil can leak into the combustion chamber and cause white smoke. This is also a serious issue that requires engine repair.

In any case, it is best to address the issue promptly to prevent further damage to the engine. If you are unsure of how to proceed, it is recommended to seek the assistance of a professional mechanic.

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Conclusions

Oil coming out of the exhaust of your lawn mower can be a sign of a serious problem. By understanding the potential causes and solutions listed above, you can diagnose and fix the problem before it leads to more serious damage to your mower. Always remember to follow the manufacturer’s recommendations for oil changes and maintenance to keep your mower running smoothly.