1. Introduction
This manual provides essential information for the installation, operation, and maintenance of your Ewon P25 P35 Trimmer Head. This replacement trimmer head is designed for various McCulloch string trimmer models, offering a reliable solution for your lawn care needs. Please read this manual thoroughly before installation and use to ensure safe and efficient operation.
2. Safety Information
Always prioritize safety when working with power tools. Failure to follow these instructions may result in serious injury.
- Read the Trimmer Manual: Always refer to your string trimmer's original instruction manual for specific safety guidelines and operating procedures.
- Wear Protective Gear: Always wear appropriate personal protective equipment (PPE), including safety glasses or goggles, hearing protection, heavy-duty gloves, long pants, and sturdy footwear.
- Disconnect Power: Before performing any installation, maintenance, or inspection, ensure the string trimmer's engine is off and the spark plug wire is disconnected (for gasoline models) or the battery is removed (for electric/cordless models).
- Inspect Before Use: Before each use, inspect the trimmer head for any damage, cracks, or loose parts. Do not use if damaged.
- Use Correct Parts: Only use replacement parts and accessories specified for your trimmer model.
- Keep Bystanders Away: Ensure no people or pets are in the immediate work area.
3. Package Contents
Verify that all items are present in the package:
- 1 x Ewon P25 P35 Trimmer Head
- 8 x Thread Adapters (various sizes)
- 1 x Spool of Trimmer Line

Image: The Ewon P25 P35 Trimmer Head shown with the eight included thread adapters and a spool of trimmer line.
4. Product Overview and Parts Identification
Familiarize yourself with the components of the trimmer head before installation.

Image: Exploded view showing individual components of the trimmer head, including the Eyelet, Cover, Spool With Line, Bumper, Spring, M10 x 1.25 Left Hand Thread, and Housing.
The trimmer head consists of several key parts that work together to feed and cut the line. Understanding these components will assist in installation and maintenance.
5. Compatibility
This Ewon P25 P35 Trimmer Head is compatible with a wide range of McCulloch string trimmer models. Please verify your machine model before purchase and installation.
Compatible McCulloch String Trimmer Models:
- Cabrio Plus 257 B (9539007-40)
- Cabrio Plus 257 L (9539007-39)
- Cabrio Plus 297 L (2007)
- Cabrio Plus 347 B (9539007-47)
- Cabrio Plus 347 L (9539007-46)
- Cabrio Plus 407 B (9539007-49)
- Cabrio Plus 407 L (9539007-48)
- Colibri II (9527154-59)
- Colibri II Plus (9527156-99)
- HG55 (2003)
- Li-40T (9671032-01, 9671032-62)
- Premio B (9539007-43)
- Premio BTX (9539007-44)
- Premio EX (9539007-41)
- Premio L (9539007-42)
- T26CS (9672077-01)
- T251 (9527156-99)
- TM252 (9527156-22)
- TM281 (9527154-67)
- Trim Mac SL (9527154-62)
This trimmer head replaces original part numbers P25, P35, 577 61 59 01, 5310250-01, 9527155-09, and 9527155-26.

Image: The trimmer head displayed with a selection of thread adapters, illustrating its broad compatibility with different shaft sizes and thread types.
6. Installation Instructions
Follow these steps carefully to install the new trimmer head.
- Prepare the Trimmer: Ensure the string trimmer is turned off, the engine is cool, and the spark plug wire is disconnected (or battery removed for electric models) to prevent accidental starting.
- Remove Old Trimmer Head:
- Locate the locking hole on the trimmer's gear case or shaft. Insert a small screwdriver or pin into this hole to lock the shaft.
- Rotate the old trimmer head counter-clockwise (for most models, it's left-hand thread) to loosen and remove it. Some models may require a wrench.
- Select Correct Adapter: Identify the correct thread adapter from the included set that matches your trimmer's shaft. The adapters come in various sizes and thread directions (right-hand or left-hand). Refer to your trimmer's manual if unsure.
- Install Adapter (if needed): If your trimmer requires an adapter, screw it onto the trimmer shaft. Ensure it is snug.
- Install New Trimmer Head:
- Align the new Ewon P25 P35 Trimmer Head with the shaft or the installed adapter.
- Rotate the trimmer head clockwise (for left-hand thread) or counter-clockwise (for right-hand thread) until it is securely tightened. Continue to hold the shaft locked with the pin.
- Remove the locking pin.
- Verify Installation: Gently tug on the trimmer head to ensure it is firmly attached and does not wobble.

Image: A view of the trimmer head's underside, highlighting the central thread connection point where the appropriate adapter is installed.
7. Operating Instructions
This trimmer head features a bump-feed mechanism for line advancement.
- Starting the Trimmer: Follow your string trimmer's manufacturer instructions to start the engine/motor.
- Advancing Trimmer Line:
- While the trimmer head is spinning at full speed, gently tap the bottom of the trimmer head on a firm, non-abrasive surface (e.g., grass, dirt).
- The impact will release a small amount of line from the spool.
- The line cutting blade on your trimmer's guard will automatically trim the line to the correct length.
- Cutting Technique: Maintain a safe distance from objects and bystanders. Use a sweeping motion to cut grass and weeds. Avoid hitting hard surfaces like concrete or rocks, as this can damage the line and the trimmer head.
8. Maintenance
Regular maintenance ensures optimal performance and extends the life of your trimmer head.
- Cleaning: After each use, clean the trimmer head to remove grass clippings, dirt, and debris. Use a stiff brush or cloth. Do not use harsh chemicals.
- Line Replacement: When the trimmer line runs out or becomes too short, it needs to be replaced.
- Ensure the trimmer is off and disconnected from power.
- Press the tabs on the side of the trimmer head cover and remove the cover.
- Remove the old spool.
- Take the new trimmer line (or rewind the existing spool with new line, ensuring it's wound tightly and evenly in the direction indicated on the spool).
- Feed the ends of the line through the eyelets on the trimmer head housing.
- Place the spool back into the housing, ensuring it seats correctly.
- Reattach the cover, ensuring it clicks securely into place.
- Inspect for Damage: Periodically inspect the trimmer head for cracks, excessive wear, or damage to the eyelets. Replace the head if significant damage is found.
9. Troubleshooting
If you encounter issues with your trimmer head, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Line does not advance when bumped. |
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| Trimmer head wobbles or vibrates excessively. |
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| Line breaks frequently. |
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10. Specifications
| Feature | Detail |
|---|---|
| Product Dimensions | 3.94 x 3.94 x 2.36 inches |
| Item Weight | 1.1 pounds |
| Manufacturer | Ewon |
| Country of Origin | China |
| Compatible Part Numbers | P25, P35, 577 61 59 01, 5310250-01, 9527155-09, 9527155-26 |
11. Warranty and Support
Warranty: This product comes with a 6-month warranty from the date of purchase.
Customer Support: If you have any questions, concerns, or require assistance, please contact Ewon customer support. We aim to answer all inquiries within 24 hours.
For support, please refer to the contact information provided with your purchase or visit the Ewon official website.





