Symptoms
- Oil spots or puddles under the mower when parked
- Oil visibly seeping from around the crankcase or oil fill area
- Oil level drops faster than normal between checks
- May smell burning oil while running
Likely causes
- CommonOverfilled crankcaseExcess oil can seep out through seals or the breather under pressure.
- CommonMower tipped the wrong wayTipping with the wrong side down lets oil escape through the air filter or spark plug hole.
- PossibleWorn crankcase gasket or sealGaskets harden and shrink with age, allowing oil to seep past them.
- PossibleCracked oil fill tube or drain plug not tightenedA loose or damaged component near the fill/drain point is an easy source to overlook.
What to do
- Check the oil level and drain any excess down to the correct fill line.
- Confirm the drain plug (if equipped) is tightened securely after any oil change.
- Wipe down the crankcase and look closely to trace exactly where oil is seeping from.
- Always tip the mower with the air filter and carburetor side facing up during storage or maintenance, per the manual.
- If a specific gasket or seal is visibly leaking, it can often be replaced without removing the whole engine.
- Continue monitoring the oil level regularly if a small seep persists, and address it before it becomes worse.
Tools and parts
- Oil drain pan
- Wrench set
Crankcase gasketSearch: “lawn mower engine gasket kit”
When to call a pro
A worn crankcase seal or gasket replacement is a straightforward job for a small engine shop if you'd rather not disassemble the engine.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.