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Jennifer Clark PhDSep 5, 2025
Why is my Ferris 5901605 engine knocking?
- CCindy RaySep 5, 2025
If your Ferris Lawn Mower engine is knocking, it could be due to a low oil level. Check the oil level and add oil as needed. It could also be due to using the wrong grade of oil. Refer to the engine manual for the correct oil grade.



