1. Product Overview
This manual provides instructions for the THTEN 59843700 Trimmer Replacement Lever. This component is designed to replace the original line feeder lever in compatible Black & Decker string trimmers, ensuring proper line advancement during operation.

Figure 1: A pack of six THTEN 59843700 Trimmer Replacement Levers, designed for compatibility with Black & Decker ST7000 and ST7700 models.
1.1 Compatibility
The THTEN 59843700 Trimmer Replacement Lever is compatible with the following Black & Decker trimmer models:
- Black & Decker ST7700 Type 1
- Black & Decker ST7000 Type 1
This lever replaces part numbers 59843700, 598437-00, and 714394862341.

Figure 2: This image highlights the compatibility of the replacement lever with Black & Decker ST7700 Type 1 and ST7000 Type 1 trimmers, along with part numbers 598437-00, 59843700, and 714394862341.
2. Installation Guide
Follow these steps to replace the line feeder lever in your compatible Black & Decker trimmer. Always ensure the trimmer is unplugged or the battery is removed before beginning any maintenance or installation.
2.1 Required Tools
- Small Phillips head screwdriver
- Work gloves (recommended for hand protection)
2.2 Installation Steps
- Prepare the Trimmer: Disconnect the trimmer from its power source (unplug or remove battery). Place the trimmer head on a clean, flat surface.
- Locate the Lever: Identify the existing line feeder lever within the trimmer head assembly. It is typically secured by a small screw.
- Remove Old Lever: Use a Phillips head screwdriver to carefully remove the screw holding the old lever in place. Gently lift and remove the old lever.
- Install New Lever: Position the new THTEN 59843700 replacement lever into the designated slot. Ensure it is oriented correctly; if it does not fit easily, rotate it 180 degrees. It should slide into place without excessive force.
- Secure New Lever: Reinsert and tighten the screw to secure the new lever. Do not overtighten.
- Test Functionality: Reconnect the power source and briefly test the trimmer to ensure the line feeds correctly.

Figure 3: A visual guide demonstrating the four steps for installing the THTEN 59843700 Trimmer Replacement Lever into a trimmer head. Step 1 shows removing a screw, Step 2 shows the internal mechanism, Step 3 shows placing the new lever, and Step 4 shows securing it.
3. Operating the Trimmer with New Lever
The THTEN 59843700 Trimmer Replacement Lever is an integral part of the trimmer's auto-feed mechanism. Once installed, it facilitates the release of cutting line from the spool as needed during operation. No special operating procedures are required beyond the standard use of your Black & Decker trimmer.

Figure 4: An image depicting a person using a string trimmer, with an inset showing the THTEN 59843700 Trimmer Replacement Lever, illustrating its role in the trimmer's operation.

Figure 5: A close-up view of a trimmer head, pointing out the features of the replacement lever, including its wear-resistant and durable material, auto-feed function, and ease of installation.
4. Maintenance
The THTEN 59843700 Trimmer Replacement Lever is designed for durability. Regular maintenance of your trimmer, including cleaning the trimmer head and ensuring no debris obstructs the lever's movement, will help prolong its lifespan. Periodically inspect the lever for signs of wear or damage. Replace the lever if it appears worn or if line feeding issues persist.
5. Troubleshooting
5.1 Line Not Feeding Correctly
- Incorrect Installation: Ensure the lever is installed in the correct orientation. If it was difficult to install or does not sit flush, it might be backward. Remove and re-install, rotating it 180 degrees if necessary.
- Obstruction: Check for any grass, dirt, or debris that might be preventing the lever from moving freely. Clean the trimmer head thoroughly.
- Worn Spool or Line: Ensure the trimmer line is properly wound on the spool and that the spool itself is not damaged.
- Lever Damage: Inspect the lever for any cracks, breaks, or excessive wear that might impede its function. Replace if damaged.
6. Specifications
| Feature | Detail |
|---|---|
| Brand | THTEN |
| Model Number | 59843700 Lever |
| Part Numbers | 59843700, 598437-00, 714394862341 |
| Material | Acrylonitrile Butadiene Styrene (ABS), Metal |
| Color | Black |
| Unit Count | 6 Count |
| Special Feature | Easy to Install |
7. Warranty and Support
For any issues or assistance with your THTEN 59843700 Trimmer Replacement Lever, please contact the manufacturer directly. THTEN offers after-sales assurance and support for their products.
For support inquiries, please refer to the contact information provided with your purchase or visit the official THTEN store on Amazon: THTEN Amazon Store