Description
Overview:
This Genuine Stihl worm gear (part number 1122 640 7105) is a precision-moulded drive component for heavy-duty chainsaws, including the MS660 and 064. Made from hard-wearing polymer (nylon) with a helical form, it transfers rotation reliably to the saw's drive system, helping to power functions such as the chain oiling mechanism. Replacing a worn or stripped worm restores smooth, consistent operation, reduces unnecessary wear on mating parts, and supports dependable lubrication and performance. Built to OEM standards for fit and alignment, it is suitable for professional forestry, arborist work, and demanding DIY tasks. As a Genuine Part from Stihl, it offers assured compatibility with the specified models and long service life under typical chainsaw operating conditions.
Key Features:
- Genuine Stihl part for correct fit and reliable performance
- Durable polymer construction with low-friction helical profile
- Helps maintain consistent bar and chain lubrication under load
- Precision moulding supports smooth, efficient power transfer
- Resistant to oil and heat for longer service life
- Designed for the MS660/066/064 family and related models
- Supports quick replacement with standard hand tools
- Reduces wear on mating gears by restoring correct engagement
- Lightweight component engineered for high rotational speeds
- OEM specification ensures proper clearances and alignment
Typical Applications:
Ideal for replacing a worn or damaged drive worm on Stihl professional and farm-grade chainsaws used in forestry, arboriculture, site clearance, firewood processing, and general grounds maintenance. Helps restore dependable chain lubrication and smooth running after symptoms such as intermittent oiling, slipping drive, or abnormal noise from the clutch side.
Also known as:
Oiler drive gear, oiler worm, worm wheel, worm screw, lubricator drive, helical drive, drive scroll, oil pump driver, drive cog for oiler, ancillary drive gear.
Fits Models:
064, 066, MS 640, MS 650, MS 660, MS640, MS650, MS660
Alternate Part Numbers:
1122-640-7105, 11226407105
