1. Important Safety Instructions
Read all instructions carefully before operating the grass trimmer. Failure to follow these instructions may result in electric shock, fire, and/or serious injury.
- Personal Safety: Always wear eye protection, long pants, and sturdy footwear when operating the trimmer. Do not operate when barefoot or wearing open-toed sandals.
- Work Area Safety: Keep the work area clean and well-lit. Remove all debris, rocks, wires, or other objects that could be thrown by the blade. Keep bystanders, children, and pets at least 15 meters (50 feet) away from the operating area.
- Electrical Safety: This is a battery-powered tool. Use only the specified battery pack and charger. Do not expose the battery pack or tool to rain or wet conditions.
- Tool Use and Care: Do not force the tool. Use the correct tool for your application. Maintain the tool with care. Keep cutting blades sharp and clean for better and safer performance.
- Battery Safety: Do not incinerate the battery pack even if it is severely damaged or completely worn out. The battery can explode in a fire.
2. Package Contents
Verify that all items listed below are included in your package. If any parts are missing or damaged, contact SEYVUM customer service.
- SEYVUM Grass Trimmer Unit (MJ8604)
- Plastic Blades (pre-installed or separate)
- Safety Guard
- Auxiliary Handle
- Battery Pack (if included in kit)
- Battery Charger (if included in kit)
- User Manual
3. Setup and Assembly
The SEYVUM MJ8604 grass trimmer requires minor assembly before first use. Ensure the battery is removed before assembly.
- Attach the Safety Guard: Align the safety guard with the mounting slots on the trimmer head. Secure it firmly using the provided screws or clips. Ensure it is properly seated and does not wobble.
- Install the Auxiliary Handle: Slide the auxiliary handle onto the main shaft. Adjust its position for comfortable operation and tighten the locking mechanism or screws.
- Insert Plastic Blades: If not pre-installed, carefully attach the plastic blades to the trimmer head according to the diagram. Ensure they click into place securely.

Image: SEYVUM MJ8604 Grass Trimmer with safety guard and handle attached. This image shows the fully assembled trimmer, highlighting the main unit, safety guard, and auxiliary handle.
4. Operating Instructions
Follow these steps for safe and effective operation of your SEYVUM MJ8604 grass trimmer.
- Charge the Battery: Before first use, fully charge the battery pack using the provided charger. Refer to the charger's instructions for charging times.
- Insert the Battery: Once charged, slide the battery pack into the battery compartment on the trimmer until it clicks into place. Ensure it is firmly seated.
- Starting the Trimmer: Hold the trimmer firmly with both hands. Press the safety lock-off button (if present) and then squeeze the trigger switch to start the motor.
- Trimming Technique: Move the trimmer in a sweeping motion, keeping the cutting head slightly above the ground. Avoid hitting hard objects or thick brush to prevent blade damage.
- Stopping the Trimmer: Release the trigger switch to stop the motor. Always remove the battery pack when not in use or before performing any maintenance.
5. Maintenance
Regular maintenance ensures optimal performance and extends the life of your SEYVUM MJ8604 grass trimmer.
- Cleaning: After each use, remove the battery and clean the trimmer head and safety guard with a dry cloth or soft brush. Remove any grass clippings or debris. Do not use water or solvents.
- Blade Replacement: Inspect plastic blades regularly for wear or damage. Replace worn blades promptly to maintain cutting efficiency. Refer to the diagram for proper blade replacement.
- Battery Care: Store the battery pack in a cool, dry place away from direct sunlight. Do not store the battery in a discharged state for extended periods.
- Storage: Store the trimmer in a dry, secure location out of reach of children.
6. Troubleshooting
If you encounter issues with your SEYVUM MJ8604 grass trimmer, refer to the following table for common problems and solutions.
| Problem | Possible Cause | Solution |
|---|---|---|
| Trimmer does not start | Battery not charged or improperly inserted; Safety lock-off not engaged; Faulty switch | Charge battery and reinsert; Ensure safety lock-off is pressed before trigger; Contact customer service |
| Poor cutting performance | Worn or damaged blades; Grass too thick; Trimmer head clogged | Replace plastic blades; Trim in smaller passes; Clean trimmer head |
| Excessive vibration | Damaged blade; Loose components | Inspect and replace blade; Check all fasteners for tightness |
7. Specifications
Technical specifications for the SEYVUM MJ8604 Grass Trimmer.
- Brand: SEYVUM
- Model: MJ8604
- Power Source: Battery-powered
- Color: Green
- Cutting Width: 10 inches
- Product Dimensions (L x W): 9.1 cm x 5.5 cm
- Cordless: Yes
- Assembly Required: Yes
- Recommended Use: Trimming
8. Warranty and Support
SEYVUM products are manufactured to high-quality standards. For warranty information or technical support, please refer to the warranty card included with your product or visit the official SEYVUM website. Keep your purchase receipt as proof of purchase.
For further assistance, please contact SEYVUM customer service through the contact information provided on our website or in your product documentation.