How to Replace Weed Eater String Stihl? Quick Guide

Introduction

Replacing the string on your Stihl weed eater is a routine maintenance task that keeps your tool performing at its best. Whether you are dealing with a worn-out line or switching to a different gauge for tougher weeds, knowing how to replace weed eater string Stihl models correctly can save you time and frustration. This guide walks you through the entire process, from identifying your model type to choosing the right replacement line and installing it properly. We will cover automatic feed systems, manual feed heads, and everything in between, so you can tackle the job with confidence regardless of your experience level.

Table of Contents

• Why Replace the String on Your Stihl Weed Eater
• Tools You Will Need
• How to Identify Your Stihl Model
• Understanding Stihl String Types and Sizes
• Preparing Your Weed Eater for String Replacement
• Removing the Old String
• Pre-Wound Spools vs Manual Feed Heads
• Step-by-Step Guide for Automatic Feed Heads
• Step-by-Step Guide for Manual Feed Heads
• Troubleshooting Common Issues
• Comparison Table of Stihl String Options
• Tips and Best Practices
• Common Mistakes to Avoid
• When to Replace the String Regularly
• Frequently Asked Questions
• Conclusion

Why Replace the String on Your Stihl Weed Eater

The string on your Stihl weed eater wears down over time due to constant contact with concrete, asphalt, and thick vegetation. A dull or broken line reduces cutting efficiency, forcing you to apply more pressure and increasing the risk of damaging your tool or the surrounding area. Replacing the string restores optimal performance, prevents uneven cuts, and extends the lifespan of your equipment. Additionally, using the correct string type for your specific Stihl model ensures smooth operation and minimizes the chance of line tangles or premature wear.

Tools You Will Need

Before starting the replacement process, gather the following items:

• A clean cloth or rag
• Small flathead screwdriver (for some manual feed heads)
• A pair of scissors or utility knife
• The correct replacement string for your Stihl model
• A soft brush or compressed air (optional, for cleaning debris)

Having these tools on hand makes the process faster and helps prevent damage to your weed eater during disassembly.

How to Identify Your Stihl Model

Stihl produces a wide variety of weed eaters, each with slightly different string replacement procedures. To identify your model:

1. Locate the model number on the engine housing or shaft of your tool.
2. Check the user manual or the official Stihl website for model-specific instructions.
3. Note whether your head is an automatic feed system or a manual feed design.

Common Stihl models include the FS 38, FS 56, FS 70, FS 91, and FS 110, but the exact replacement steps may vary. Always consult your manual or Stihl’s online resources for the most accurate guidance.

Understanding Stihl String Types and Sizes

Stihl offers several string options tailored to different cutting needs:

• Standard nylon line: Ideal for general trimming of grass and light weeds.
• Heavy-duty twisted line: Better suited for thick brush and stubborn vegetation.
• Serrated or bladed line: Provides aggressive cutting power for tough jobs.

String thickness typically ranges from 0.080 inch to 0.105 inch. Thicker lines are more durable but require a more powerful motor. Always match the string diameter recommended by Stihl for your specific model to avoid overloading the engine or causing line jams.

Preparing Your Weed Eater for String Replacement

Safety comes first. Follow these preparation steps before removing the old string:

1. Turn off the engine and disconnect the spark plug wire to prevent accidental starting.
2. Allow the engine to cool completely to avoid burns.
3. Place the tool on a stable surface or workbench.
4. Remove any dirt, grass clippings, or debris from the string head using a soft brush.

A clean workspace and proper safety measures make the replacement process smoother and reduce the risk of injury.

Removing the Old String

The method for removing the old string depends on your head type:

For Automatic Feed Heads

1. Press the release button or tab on the side of the spool housing.
2. Pull the spool straight out while holding the head steady.
3. Remove the old string by unwinding it from the spool.

For Manual Feed Heads

1. Locate the small screw or locking mechanism on the head.
2. Use a screwdriver to loosen or remove the screw.
3. Take off the outer cap and spool assembly.
4. Unwind the old string from the spool.

In both cases, inspect the spool and head for wear or damage. Replace any cracked or broken components before installing new string.

Pre-Wound Spools vs Manual Feed Heads

Stihl provides pre-wound spools for many models, which simplify the replacement process significantly. These spools come pre-loaded with the correct amount and type of string, eliminating guesswork. However, some users prefer manually winding their own spools to customize line thickness or save money. Pre-wound spools are ideal for beginners, while manual winding gives experienced users more control over their setup.

Step-by-Step Guide for Automatic Feed Heads

If your Stihl weed eater uses an automatic feed system, follow these detailed steps:

1. Turn off the tool and disconnect the spark plug. This prevents accidental starts during maintenance.
2. Press the release mechanism. Most automatic feed heads have a small button or lever on the side of the spool housing. Press it firmly to release the spool.
3. Pull out the spool. Gently pull the spool straight up while keeping the head stable. The old string should come out with it.
4. Inspect the spool. Check for cracks, grooves, or debris that might interfere with the new string.
5. Insert the new spool. If using a pre-wound spool, align the arrows or notches and push it back into place until it clicks.
6. Reconnect the spark plug. Once the spool is secure, reconnect the spark plug wire.
7. Test the line feed. Pull the starter cord gently to ensure the string feeds smoothly without tangling.

This process typically takes less than five minutes once you are familiar with your model.

Step-by-Step Guide for Manual Feed Heads

For manual feed heads, the process requires a bit more attention to detail:

1. Safety first. Disconnect the spark plug and ensure the tool is off and cool.
2. Remove the outer cap. Depending on your model, you may need to twist or unscrew the cap counterclockwise.
3. Take out the spool. Lift the spool assembly out of the head housing.
4. Clean the interior. Use a soft brush to remove any trapped debris or old string fragments.
5. Wear the new string. Cut a length of new string appropriate for your model, usually around 15 to 20 feet. Insert one end into the hole in the center of the spool and begin winding in the direction indicated by the arrows on the spool.
6. Secure the spool. Place the spool back into the head housing, ensuring the string exits through the correct slot.
7. Replace the cap. Twist or screw the cap back on securely.
8. Test the line. Manually pull the string to confirm it feeds freely and does not tangle.

Manual winding allows you to adjust the tension and amount of line, giving you greater flexibility for different trimming tasks.

Troubleshooting Common Issues

Even with careful attention, problems can arise during string replacement. Here are some common issues and their solutions:

Line Tangling Inside the Head

If the string becomes tangled inside the head, disassemble the spool and rewind it carefully, ensuring the string lies neatly in the grooves. Always follow the winding direction marked on the spool.

String Not Feeding Properly

Check that the string is threaded through the correct exit hole and that the spool is seated properly. A misaligned spool can prevent smooth line feed.

Spool Won’t Click Into Place

Ensure all debris is cleared from the head housing and that the spool is aligned with the notches. Forcing the spool can damage internal components.

Engine Struggling or Overloading

This often indicates the string is too thick or wound too tightly. Switch to a lighter gauge line or reduce the amount of string on the spool.

Addressing these issues promptly prevents further damage and keeps your Stihl running efficiently.

Comparison Table of Stihl String Options

This table helps you choose the best string option based on your trimming needs and budget.

Tips and Best Practices

• Always disconnect the spark plug before starting. Even a momentary spark can cause injury.
• Use the correct string diameter. Thicker lines offer more durability but can strain smaller motors.
• Wind the string neatly and evenly. Overlapping or loose windings lead to tangles and uneven feed.
• Keep the head clean. Debris buildup can interfere with spool rotation and line feed.
• Replace the string regularly. Don’t wait until it’s completely worn out; proactive replacement maintains performance.
• Store spare string in a dry place. Moisture can weaken nylon lines over time.
• Refer to your manual. Each Stihl model may have unique features or requirements.

Following these best practices ensures consistent performance and prolongs the life of your weed eater.

Common Mistakes to Avoid

Avoiding these frequent errors can save you time and prevent damage to your tool:

• Using the wrong string size. Too thick or too thin can cause engine strain or poor cutting performance.
• Overwinding the spool. Too much string increases the chance of tangling and binding.
• Ignoring the winding direction. Winding against the arrow marks leads to feeding problems.
• Skipping the safety steps. Failing to disconnect the spark plug is dangerous and unnecessary.
• Not cleaning the head. Debris left inside can damage the new string or spool mechanism.
• Rushing the process. Taking time to follow each step carefully results in better outcomes.

By being mindful of these pitfalls, you can complete the replacement with minimal hassle.

When to Replace the String Regularly

Regular string replacement is key to maintaining your Stihl weed eater’s performance. As a general rule:

• Inspect the string before each use. Look for fraying, breaks, or significant wear.
• Replace every 2 to 3 months with regular use, or sooner if the line becomes dull or damaged.
• Switch to heavy-duty line seasonally. During peak growing seasons, thicker lines handle tougher vegetation better.
• Keep a spare spool on hand. Having a backup ensures you’re never caught without a working tool.

A proactive replacement schedule keeps your tool ready for any trimming challenge.

Frequently Asked Questions

Can I use any brand of string on my Stihl weed eater?

While many generic strings are compatible, Stihl recommends using genuine Stihl replacement line for optimal performance and longevity. Non-OEM strings may vary in thickness or material quality, potentially affecting cutting efficiency and motor strain.

How often should I replace the string?

For regular users, inspecting the string before each use and replacing it every 2 to 3 months is ideal. If you notice fraying, frequent breaks, or reduced cutting power, replace the string immediately regardless of the timeline.

What size string does my Stihl model use?

String size varies by model. Common diameters include 0.080, 0.095, and 0.105 inches. Always consult your user manual or Stihl’s official website to confirm the correct size for your specific model.

Is it better to use a pre-wound spool or wind my own?

Pre-wound spools offer convenience and consistency, making them ideal for beginners. Manually wound spools allow customization and cost savings, but require more skill and attention to detail.

My string keeps tangling. What am I doing wrong?

Tangling usually results from incorrect winding direction, overwinding, or debris in the head. Carefully follow the arrow marks on the spool, wind evenly, and keep the head clean to prevent tangles.

Can I replace the string myself, or should I take it to a professional?

Replacing the string on most Stihl weed eaters is a straightforward DIY task. However, if you encounter persistent mechanical issues or feel uncomfortable with the process, consulting an authorized Stihl dealer is always a safe option.

Conclusion

Learning how to replace weed eater string Stihl models is a valuable skill that enhances your tool’s performance and longevity. Whether you are using an automatic feed head or a manual feed system, the process is straightforward when you have the right tools, the correct string, and a clear understanding of your model’s requirements. By following the step-by-step instructions outlined in this guide, you can confidently replace the string on your Stihl weed eater and keep it running at peak efficiency. Remember to prioritize safety, choose the appropriate string type for your trimming needs, and perform regular maintenance to avoid unexpected downtime. With a little practice, string replacement becomes a quick and routine task that keeps your garden looking its best.