Chainsaw [Lifetime Warranty] 3/8" 7T Clutch Drum Sprocket with Bearing Washer E-Clip Worm Gear - Compatible with Stihl 017 018 021 023 MS170 MS180 MS210 MS230 MS250 Chainsaw - Replaces 1123 640 2003, 1123 640 2073
Clutch drum sprocket, clutch assembly, worm gear, bearing, washer, and E-clip for Stihl chainsaws.
Clutch drum sprocket, bearing, washer, E-clip, and worm gear kit for Stihl chainsaws.
Dimensional diagram of 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws with measurement labels.
High-strength steel 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws.
Clutch drum, sprocket, bearing, washer, E-clip, and worm gear kit for Stihl chainsaws.
BlueStars replacement clutch drum sprocket compatibility graphic for Stihl MS250 and compatible chainsaw models.
Infographic showing 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws with performance benefits.
Instructional graphic showing how to install a clutch drum sprocket on a Stihl MS250 chainsaw.
Clutch drum sprocket kit with bearing, washer, E-clip, and worm gear for Stihl chainsaws.
Clutch drum sprocket, clutch assembly, worm gear, bearing, washer, and E-clip for Stihl chainsaws.
Clutch drum sprocket, bearing, washer, E-clip, and worm gear kit for Stihl chainsaws.
Dimensional diagram of 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws with measurement labels.
High-strength steel 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws.
Clutch drum, sprocket, bearing, washer, E-clip, and worm gear kit for Stihl chainsaws.
BlueStars replacement clutch drum sprocket compatibility graphic for Stihl MS250 and compatible chainsaw models.
Infographic showing 3/8" 7T clutch drum sprocket and clutch assembly for Stihl chainsaws with performance benefits.
Instructional graphic showing how to install a clutch drum sprocket on a Stihl MS250 chainsaw.
Clutch drum sprocket kit with bearing, washer, E-clip, and worm gear for Stihl chainsaws.
Lifetime Warranty

[Lifetime Warranty] 3/8" 7T Clutch Drum Sprocket with Bearing Washer E-Clip Worm Gear - Compatible with Stihl 017 018 021 023 MS170 MS180 MS210 MS230 MS250 Chainsaw - Replaces 1123 640 2003, 1123 640 2073

Save 13%
0.00
$20.47
$23.54
$20.47
In stock
Fast delivery

Secure and trusted checkout with

  • Visa
  • Mastercard
  • American Express
  • PayPal
  • Diners Club
  • Discover
Contact for wholesale
🛠️
CONFIRM THE FIT FOR YOUR MODEL
Enter your model number

3/8" 7T Clutch Drum Sprocket with Bearing Washer E-Clip Worm Gear

Key Features

  • Sprocket Pitch: 3/8 inch
  • Sprocket Tooth Count: 7
  • Material: High-strength metal alloy construction
  • Complete assembly kit for chainsaw clutch and oil pump drive
  • Includes: 1x Clutch Drum Sprocket, 1x Needle Bearing, 1x Clutch Washer, 1x E-Clip, 1x Worm Gear

Replaces / Cross-Reference Part Numbers

  • Sprocket/Clutch Drum: 1123-640-2003, 1123-640-2073, 1123-640-2074, 1123-160-2050
  • Clutch: 1123-160-2001, 1123-007-1001
  • Worm Gear: 1123-640-7102
  • Bearing / Washer / E-Clip: 9512-933-2260, 0000-958-1022, 9460-624-0801

Compatibility & Fitment

  • Designed for specific Stihl chainsaw models.
  • Fits Stihl: 017, 018, 021, 023, 025
  • Fits Stihl: MS 170, MS 180, MS 210, MS 230, MS 250
  • Note: Always verify part number and model to ensure correct fitment.

When to Replace

  • Visible wear, grooving, or damage on the sprocket teeth
  • Chain slips, binds, or derails frequently
  • Grinding or abnormal noise from the clutch housing
  • Chain continues to spin at idle

Installation Tips

  • Disconnect spark plug wire before beginning service.
  • Use a piston stop tool to prevent engine rotation during clutch removal.
  • Clean all components and the clutch housing area before installing new parts.
  • Lightly grease the needle bearing before installation.
  • Ensure the E-clip is properly and securely seated in its groove.
Product image 1
Product image 2
Product image 3
Product image 1
Product image 2
  • WIDE COMPATIBILITY

    WIDE COMPATIBILITY

    Compatible with specific Stihl Chainsaw model: 017 018 021 023 025 MS170 MS180 MS210 MS230 MS250.
  • DURABLE MATERIAL

    DURABLE MATERIAL

    This part is made of sturdy material which is flexibility and flame-retardant, enhancing durability
  • SAVING SOLUTION

    SAVING SOLUTION

    Enjoy the great feeling when your chainsaw is repaired and works properly like before
  • IMPORTANT NOTE

    IMPORTANT NOTE

    This is a replacement part designed to be compatible with certain appliances. Any brand names mentioned are used solely to indicate compatibility
THE REPLACEMENT PART THAT KEEP YOUR YARD LOOKING FRESH!

THE REPLACEMENT PART THAT KEEP YOUR YARD LOOKING FRESH!

FAQ

This kit is compatible with a wide range of Stihl chainsaws, including the 017, 018, 019, 019T, 021, 023, 025, MS170, MS171, MS180, MS181, MS190, MS191, MS192, MS210, MS211, MS230, and MS250 series.
This assembly replaces Stihl OEM part numbers 1123 640 2003 and 1123 640 2073.
You should inspect the sprocket teeth for deep grooving or wear caused by the drive links of the chain. If the chain does not spin freely, or if you notice significant vibration and uneven wear on the chain drive links, the drum and sprocket assembly likely needs replacement.
To replace the clutch drum, you will need a piston stop tool to lock the engine, a clutch removal tool (or a suitable punch and hammer to turn the clutch clockwise to loosen), and a flat-head screwdriver or pliers to remove the E-clip and washer.
Yes, always inspect the needle bearing for signs of heat discoloration or lack of lubrication. It is best practice to replace the needle bearing whenever you install a new clutch drum to ensure smooth rotation and prevent premature failure of the new part.
The worm gear drives the oil pump. Since it is housed behind the clutch drum, it is highly recommended to replace it during a clutch service to ensure consistent chain lubrication and to avoid having to disassemble the clutch assembly again in the near future.