Product Overview
This manual provides instructions for the Arnold Replacement Trimmer Line. This product is a 10-count package of .155" diameter trimmer line, with each piece measuring 18.5" in length. It is designed for use with string trimmer mowers, specifically compatible with Yard-Man 250 Series Walk Behind String Trimmer Mowers manufactured in 2001 and later. It also fits other trimmer mower brands that utilize .155" diameter line.

Figure 1: Packaging of the Arnold Replacement Trimmer Line. The image shows a clear plastic package containing multiple pre-cut lengths of red trimmer line. The packaging displays product information such as "PROFESSIONAL GRADE" and ".155" diameter."
Setup and Installation
Proper installation of the trimmer line is crucial for safe and effective operation. Always refer to your string trimmer mower's specific user manual for detailed instructions on how to access and replace the trimmer line.
- Safety First: Before beginning, ensure your string trimmer mower is turned off and the spark plug wire is disconnected (for gasoline models) or the battery is removed (for electric/cordless models) to prevent accidental starting.
- Identify Trimmer Head Type: Determine if your trimmer head uses pre-cut lines, a spool, or a bump-feed mechanism. This Arnold product consists of pre-cut lines.
- Remove Old Line (if applicable): If old line segments are present, carefully remove them from the trimmer head.
- Insert New Line: Locate the designated holes or slots on your trimmer head for inserting the pre-cut lines. Insert one end of the 18.5" line into the hole and pull it through until it is securely seated and balanced. Ensure both ends of the line are of equal length extending from the head.
- Repeat for All Lines: Insert the required number of lines according to your trimmer head's design.
- Verify Secure Fit: Gently tug on each line to ensure it is firmly seated and will not dislodge during operation.
Note: The .155" diameter of this line is a standard heavy-duty size suitable for tougher trimming tasks. Ensure your trimmer mower is designed to accommodate this diameter.
Operating Guidelines
Once the new trimmer line is installed, follow your string trimmer mower's operating instructions. The performance of the trimmer line is directly related to the proper use of the trimmer itself.
- Wear Protective Gear: Always wear safety glasses, long pants, sturdy footwear, and hearing protection when operating a string trimmer.
- Maintain Proper RPM: Operate the trimmer at the recommended RPM for optimal cutting efficiency and to prevent premature line wear.
- Avoid Hard Surfaces: Minimize contact with concrete, rocks, fences, and other hard surfaces, as this will rapidly wear down or break the trimmer line.
- Cutting Technique: Use a sweeping motion, cutting with the tip of the line. Avoid "digging" into the ground.
- Line Length: The 18.5" length is pre-cut for convenience. If your trimmer has a line-cutting blade on the guard, the line will be automatically trimmed to the correct length upon initial startup.
Maintenance
The Arnold Replacement Trimmer Line itself requires no specific maintenance. However, proper care of your string trimmer mower will ensure the longevity and effectiveness of the line.
- Inspect Trimmer Head: Regularly check the trimmer head for debris, cracks, or damage. A damaged head can cause uneven line wear or breakage.
- Clean Guard: Keep the trimmer guard clean, especially the line-cutting blade (if present), to ensure proper line length management.
- Store Line Properly: Store unused trimmer line in a cool, dry place away from direct sunlight. Extreme temperatures can affect the line's flexibility and durability over time.
Troubleshooting Common Issues
Most issues related to trimmer line performance are due to improper installation or operating conditions.
| Problem | Possible Cause | Solution |
|---|---|---|
| Line breaks frequently |
|
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| Line wears down too quickly |
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Specifications
- Product Name: Arnold Replacement Trimmer Line
- Model: Universal .155" Diameter Trimmer Line
- Line Diameter: .155 inches (3.94 mm)
- Line Length: 18.5 inches (47 cm) per piece
- Quantity: 10 pieces per package
- Compatibility: Designed for string trimmer mowers that accept .155" diameter pre-cut line, including Yard-Man 250 Series Walk Behind String Trimmer Mowers (2001 & after) and other compatible brands.
- Product Dimensions: 18.64 x 3.5 x 12 inches (packaging)
- Item Weight: 2.48 pounds (packaging)
- ASIN: B0044V0OF2
Warranty and Support
This product is a consumable replacement part. For specific warranty information regarding manufacturing defects, please refer to the Arnold brand's official website or contact their customer support directly. General product support and inquiries can be directed to the retailer where the product was purchased or to Arnold customer service.
For further assistance or to view other Arnold products, please visit the Arnold Store on Amazon.





