_1. Excess oil level:_ If the oil level in the engine is too high, it can cause oil to be pushed out of the breather tube and into the exhaust. Check the oil level and make sure it is at the correct level as per the manufacturer's recommendation.
_2. Worn piston rings:_ Piston rings help seal the combustion chamber and prevent oil from leaking into the cylinder. Over time, these rings can wear out and allow oil to seep into the combustion chamber, where it can be burned and expelled through the exhaust.
_3. Valve seals:_ Valve seals help to prevent oil from leaking into the combustion chamber through the valve guides. When these seals become worn or damaged, they can allow oil to leak into the combustion chamber and be burned off.
_4. Faulty oil filter:_ A faulty or loose oil filter can allow oil to bypass the filter and enter the engine, which can lead to excessive oil in the combustion chamber and eventually oil coming out of the exhaust.
_5. Damage to the engine block or head:_ If the engine block or head is cracked or damaged, it can allow oil to leak out of the engine and into the exhaust. This is a more serious problem that will require professional repair.
_6. Incorrect oil:_ Some lawn mowers require specific types of oil. Using the wrong type of oil can cause it to break down more quickly and lead to leaks.
_7. Overuse:_ Using your lawn mower for an extended period can lead to overheating, which can cause oil to thin out and leak through the exhaust.
_8. Faulty spark plug:_ A faulty spark plug can lead to incorrect combustion, generating excessive heat and causing the oil to thin and leak out from the exhaust.
If you have checked the oil level and suspect that one of the other issues listed above may be the cause, it's best to consult a professional for diagnosis and repair. Attempting to fix these problems yourself can be risky and may cause further damage to the lawn mower.
