Symptoms
- Small oil puddle under the saw when stored upright
- Oil drips from the bar area even when not in use
- Oil level drops between uses without running the saw
- Visible oil residue on the underside of the saw
Likely causes
- CommonGravity drainage through the oiler systemMany saws will slowly drip a small amount of residual oil through the bar when stored, especially if left on their side.
- CommonCracked or loose oil reservoir capA worn cap gasket can let oil seep out around the fill point.
- PossibleCracked oil reservoir tankAge or impact damage can crack the plastic tank, causing a steady leak.
- PossibleFailed oil pump sealA worn seal around the oil pump shaft can leak even when the saw isn't running.
- Less commonOverfilled reservoirFilling past the fill line can cause oil to weep out during temperature changes.
What to do
- Store the saw upright or bar-down as recommended in the manual to minimize gravity drainage.
- Check the oil reservoir cap and its rubber gasket for cracks or a loose fit, and replace if worn.
- Wipe down the tank area and check over a day or two for the source of a new leak versus just residual drips.
- Inspect the reservoir itself for visible cracks, especially near mounting points.
- Check that you haven't overfilled the tank past its marked line.
- If the leak is significant and continuous rather than a few drops, the oil pump seal may need replacement.
- For a cracked tank, the saw's housing assembly typically needs professional replacement.
Tools and parts
- Clean rag
- Flashlight
Oil reservoir cap and gasketSearch: “chainsaw oil cap gasket replacement”
Oil pump sealSearch: “chainsaw oil pump seal kit”
When to call a pro
If the tank itself is cracked or the oil pump seal is leaking heavily, a small-engine shop should handle the repair.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.