1. Introduction & Overview
Thank you for choosing the Greenworks 40V 15" Cordless String Trimmer. This manual provides essential information for the safe operation, assembly, maintenance, and troubleshooting of your new tool. The 40V lithium-ion platform delivers reliable power for various outdoor tasks, offering a convenient and eco-friendly alternative to gas-powered equipment.
Key Features:
- 15" Cutting Path: Equipped with a .085" dual line, bump feed head for efficient line advancement.
- Variable Speed Trigger: Allows precise control over cutting speed for maneuvering around delicate areas.
- TorqDrive System: Provides 30% more torque to power through tough grass and weeds.
- Lightweight Design: Ultra-lightweight construction and superior ergonomics reduce user fatigue.
- Easy to Use: Features a push-button start, eliminating the need for gas, fumes, or pull ropes.

Figure 1.1: Greenworks 40V 15" Cordless String Trimmer
2. Safety Information
WARNING: Always read and understand all safety warnings and instructions before operating this product.
When using the Greenworks 40V 15" Cordless String Trimmer, it is crucial to prioritize safety. Always wear appropriate personal protective equipment (PPE) including eye protection and gloves. Be aware of potential flying debris and cut hazards, and maintain a safe distance from others while operating the trimmer. Do not operate the tool in enclosed spaces or near flammable materials. Ensure the work area is clear of obstacles and bystanders.
3. What's in the Box
Your Greenworks 40V 15" Cordless String Trimmer package includes the following components:
- Greenworks 40V 15" Cordless String Trimmer Unit
- Greenworks 40V 2.0Ah Lithium-Ion Battery
- Greenworks 40V Battery Charger
- Auxiliary Handle
- Owner's Manual (this document)

Figure 3.1: Product Components Overview
4. Setup & Assembly
The Greenworks 40V 15" Cordless String Trimmer is designed for simple assembly. A screwdriver is the only tool required for initial setup.
4.1 Battery Installation
- Ensure the battery is fully charged before first use.
- Align the battery pack with the battery port on the trimmer handle.
- Slide the battery into the port until it clicks securely into place. Ensure it is fully seated to prevent accidental dislodgement during operation.

Figure 4.1: Greenworks 40V Battery
4.2 Auxiliary Handle Adjustment
The auxiliary handle can be adjusted to suit your height and provide optimal comfort during use. Loosen the adjustment knob on the handle, slide it to your desired position, and then tighten the knob securely.
5. Operating Instructions
5.1 Powering On
To start the trimmer, first press the safety lock-out button located on the handle. While holding the safety button, squeeze the variable speed trigger. The trimmer will begin operating. Release the safety button once the trimmer is running, but continue to hold the trigger to maintain power.

Figure 5.1: Double Safety Protection
5.2 Line Advancement (Bump Feed Head)
The trimmer features a bump feed head for easy line advancement. To extend the cutting line, simply tap the trimmer head gently on a firm surface while the trimmer is running. The centrifugal force will automatically feed out more line.

Figure 5.2: Bump Feed Head
5.3 Variable Speed Control
The variable speed trigger allows you to control the cutting speed. Squeeze the trigger further to increase the speed for tougher areas, and release slightly to reduce speed for more delicate trimming or edging.

Figure 5.3: Variable Speed Trigger
5.4 TorqDrive System
The integrated TorqDrive system provides 30% more torque, allowing the trimmer to power through dense grass and stubborn weeds with greater ease and efficiency.

Figure 5.4: TorqDrive System
5.5 Foldable Flower Guard
The trimmer is equipped with a foldable flower guard. This guard can be extended to help prevent accidental cutting of plants, flowers, and other delicate landscaping features.

Figure 5.5: Foldable Flower Guard
5.6 Low Noise Operation
The Greenworks 40V trimmer is designed for quiet operation, producing approximately 96dB. This allows for a more comfortable user experience compared to traditional gas-powered trimmers.

Figure 5.6: Low Noise Operation
6. Maintenance
6.1 Cleaning
After each use, disconnect the battery and clean the trimmer head and guard to remove any accumulated grass, dirt, or debris. Use a damp cloth and mild detergent if necessary. Do not use harsh chemicals or abrasive cleaners.
6.2 Line Replacement
When the cutting line needs to be replaced, ensure the trimmer is turned off and the battery is removed. The bump feed head allows for relatively easy line replacement. To access the spool, hold the buttons on both sides of the trimmer head and pull the top green part out. You can then adjust or replace the line as needed. Ensure you use the correct diameter line (.085") for optimal performance.
7. Troubleshooting
This section addresses common issues you might encounter with your Greenworks 40V 15" Cordless String Trimmer.
| Problem | Possible Cause | Solution |
|---|---|---|
| Trimmer does not start | Battery not inserted correctly or not charged; Safety button not pressed; Trigger not fully squeezed. | Ensure battery is fully seated and charged. Press safety button then squeeze trigger. |
| Line does not advance | Line tangled or too short; Incorrect line size; Spool empty. | Tap head firmly on ground while running. Check for tangled line. Replace line if empty or incorrect size. |
| Reduced cutting performance | Line too short or worn; Battery low; Heavy growth. | Advance or replace cutting line. Recharge battery. Work in smaller sections for heavy growth. |
| Battery life is short | Battery not fully charged; Operating in very dense material; Battery age. | Ensure battery is fully charged before use. Avoid continuous heavy load. Consider a higher capacity battery or replacement if old. |
8. Specifications
| Specification | Detail |
|---|---|
| Brand | Greenworks |
| Model Number | ST40B213 |
| Power Source | Battery Powered (40V Lithium-Ion) |
| Cutting Width | 15 Inches |
| Line Diameter | .085" Dual Line |
| Feed Type | Bump Feed Head |
| Item Weight | 12.32 pounds |
| Product Dimensions | 12.4"L x 11.81"W |
| Assembly Required | No (minimal setup) |
| Country of Origin | China |
9. Warranty & Support
Greenworks stands behind its products. The 40V platform tools and batteries come with a 3-year warranty to protect your investment. For detailed warranty information or technical support, please refer to the official Greenworks website or contact their customer service.
For a downloadable PDF version of the user manual, please visit: Greenworks 40V 15" Cordless String Trimmer User Manual (PDF)