Direct Answer: How to Restring a Weed Eater
Restringing a weed eater (string trimmer) means replacing or rewinding the cutting line on the trimmer head. Start by making the trimmer safe: disconnect the spark plug on gas models, or unplug the unit / remove the battery on electric models, and wear work gloves. Remove the trimmer head or bump knob to access the spool, remove the old spool and leftover line, confirm the correct line diameter, cut a single piece of line to the length indicated on the spool, wind it tightly in the direction shown by the arrow, thread the loose ends through the eyelets, reassemble the head, and test the trimmer at low throttle.
What Does Restringing a Weed Eater Mean? (Understanding the Question)
Before you pick up a new spool of line, it helps to understand exactly what “restringing” involves and why the process can look different depending on the trimmer you own.
Manual Winding vs. Pre-Wound Spool
There are two common ways to put new line into a trimmer head. The first is to buy loose trimmer line and wind it onto the existing spool yourself. The second is to buy a pre-wound spool, which comes with the line already installed; in that case, you simply remove the old spool, drop in the new one, and thread the two loose ends through the head. This guide focuses on the manual winding method, but the same disassembly and reassembly steps apply to a pre-wound spool swap.
Does “Weed Eater” Mean a Brand or Any String Trimmer?
“Weed Eater” is both a brand name and a generic term. Many people use the word to describe any gas or electric string trimmer, regardless of the manufacturer. The restringing steps below are model-agnostic, meaning they work for most common trimmer heads. If you own a Weed Eater brand unit, the same general process applies, but always check the owner’s manual for any brand-specific winding direction or head-release method.
How to Identify Your Trimmer Head Type
- Bump-feed head: You tap the head on the ground while the trimmer is running to advance more line. This is the most common type on residential trimmers.
- Fixed-line head: The line is set to a fixed cutting length and is not advanced by tapping. You replace the line when it wears down.
- Auto-feed head: The trimmer automatically feeds line as needed without a bump action. These heads often have specific winding instructions printed on the spool.
Knowing which head you have matters because it changes how the line exits the head and how much line you should leave exposed after reassembly.
Key Factors to Consider Before Restringing
Getting the prep work right prevents most restringing failures. The three things to confirm before you start are line diameter, line type, and line length.
What Line Diameter (Thickness) Does Your Trimmer Need?
The line diameter, or thickness, is usually printed on the spool itself, on the trimmer head, or in the owner’s manual. Common sizes range from 0.065 to 0.110 inches. Using the wrong thickness can cause the line to jam inside the head, feed poorly, or cut inefficiently. If you cannot find the size printed anywhere, take the old spool to the store with you, or look up your model number online.
Round vs. Twisted Line: Does It Matter?
Round line is the standard all-purpose choice and works well for most trimming jobs. Twisted or multi-sided line is often more aggressive and can cut through thicker weeds faster, but it may be noisier and can wear out quicker on hard surfaces. For a typical homeowner, round line in the diameter recommended by the manufacturer is the safest choice. If you use a heavier-duty line, confirm that your trimmer head is rated for it.
How Much Line Should You Cut?
Most spools list the recommended length, usually between 15 and 25 feet depending on the head size. If no length is listed, cut a single piece long enough to fill the spool without overlapping layers. It is better to cut a little too much than too little, because the final wraps must be tight and even. You will leave the last 4 to 6 inches unwound so the ends can be threaded through the eyelets.
Do Gas and Electric Trimmers Use the Same Steps?
Yes, the winding and threading steps are essentially the same for gas, electric corded, and battery-powered trimmers. The only real difference is the safety step: gas trimmers require disconnecting the spark plug, while electric trimmers require unplugging the unit or removing the battery.
Step-by-Step: How to Restring a Weed Eater
Follow these steps in order. Work slowly the first time, and keep the spool and head parts organized so reassembly is straightforward.
Step 1: Make the Trimmer Safe
- For gas trimmers: disconnect the spark plug wire so the engine cannot accidentally start.
- For electric trimmers: unplug the cord or remove the battery.
- Wear work gloves to protect your hands from sharp edges and old line.
- Work on a clean, flat surface so small parts do not roll away.
Step 2: Remove the Trimmer Head or Access the Spool
Depending on your model, you will either press the tabs on the side of the head and turn the cap, or use the notches on the spool to hold it while you turn the knob. On many bump-feed heads, the entire bottom cap twists off to reveal the spool. If the head will not come apart by hand, check the manual for the correct release method. Do not force it, as you may break the plastic housing.
Step 3: Remove the Old Spool and Leftover Line
Lift the old spool out of the head. Pull off any remaining line and discard it. Inspect the spool for cracks or wear; if it is damaged, replace the spool rather than reusing it. Also check the inside of the head for dirt, grass, or debris and clean it out with a cloth or small brush.
Step 4: Confirm the Line Size and Cut the New Line
Look for the line diameter marking on the spool or head, then cut a single piece of new line to the recommended length (typically 15 to 25 feet). If the spool has two separate chambers, you may need two pieces of line, one for each chamber; check the spool or manual for the exact setup.
Step 5: Anchor the Line and Wind in the Correct Direction
Find the arrow on the spool that shows the winding direction. Hook the end of the line into the anchor slot near the center of the spool, then wind the line tightly in the direction shown by the arrow. Keep each wrap flat and even, and do not let the line cross over itself. Overlapping layers cause jams and uneven feeding.
Step 6: Leave the Ends Loose and Thread the Eyelets
Stop winding when you have about 4 to 6 inches of line left. Hold the loose end so it does not unwind, and push it through the eyelet (the small exit hole) on the spool. If the spool has two line exits, repeat the process for the second piece of line. Then tuck the loose ends through the corresponding holes in the trimmer head so they stick out slightly.
Step 7: Reassemble the Head
Place the wound spool back into the head, making sure the line ends line up with the exit holes. Reattach the cap or knob and tighten it securely. Pull the line ends firmly to release any slack from inside the spool. For bump-feed heads, the line should extend just past the cutting head; for fixed-line heads, the line is already at the correct cutting length.
Step 8: Test the Trimmer
Reconnect the spark plug or battery, then start the trimmer at low throttle. Let the head spin briefly and confirm that the line does not fly out or jam. For bump-feed heads, tap the head on the ground to advance fresh line, then trim normally. If the line feeds too fast, jams, or will not advance, stop and re-check your winding direction and line diameter.
Troubleshooting Common Restringing Mistakes
Even careful DIYers run into problems after restringing. Here is how to fix the most common issues.
Why Does the Line Keep Jamming or Snapping?
Jamming is usually caused by one of three things: the line is too thick for the head, the line was wound in the wrong direction, or the line crossed over itself during winding. Remove the spool, check the diameter marking, re-wind evenly in the direction of the arrow, and try again. Snapping often happens when the line is old, brittle, or too thin for heavy weeds.
Why Is the Trimmer Feeding Too Much Line at Once?
Too much line is usually a sign that the line was wound too loosely, or that too much line was left exposed after reassembly. Pull the line ends to remove slack, and if the problem continues, re-wind the spool more tightly. On bump-feed heads, avoid tapping the head repeatedly, as each tap advances additional line.
Why Won’t the Line Advance on a Bump-Feed Head?
If tapping the head does not feed line, the line may be wound in the wrong direction, the ends may not be threaded through the eyelets correctly, or the spool may be installed upside down. Disassemble the head and verify the winding direction arrow and the spool orientation. Also confirm that the line ends are long enough to reach the cutting edge.
What If the Manual’s Steps Don’t Match My Trimmer Head?
Some heads, especially auto-feed systems and certain Weed Eater brand models, have unique winding directions or require special tools. If the steps printed on the spool or in the manual differ from the general method above, follow the manufacturer’s instructions. Forcing a head apart or winding against the arrow can damage the feed mechanism.
When to Consult the Owner’s Manual or a Professional
Most restringing jobs are simple, but there are times when you should stop and get help.
Which Trimmer Models Have Special Heads?
Auto-feed heads, speed-feed heads, and some brand-specific bump heads have their own winding procedures. The spool itself usually has printed instructions, and the owner’s manual will show the exact path for the line. If you no longer have the manual, search online using the model number printed on the trimmer or the head.
When Should You Replace the Spool or Head Instead of Just the Line?
Replace the spool if it is cracked, warped, or if the anchor slot no longer holds the line. Replace the entire head if the bump mechanism is broken, the eyelets are worn into sharp edges that keep cutting the line, or the head will not stay assembled. A damaged head can be a safety hazard, so do not try to repair it with tape or glue.
What Should You Do If You Don’t Have the Owner’s Manual?
Look for the model number on the trimmer housing, then search the manufacturer’s website for a downloadable manual or a parts diagram. You can also check the spool itself for line size and winding direction markings. If you are still unsure, a small engine repair shop can show you the correct procedure for your specific head.
Frequently Asked Questions
Can I use any trimmer line to restring my weed eater?
No. You must use the line diameter recommended for your trimmer head, usually printed on the spool or in the owner’s manual. Using a line that is too thick can jam the head, and a line that is too thin may break or cut poorly. Round line is the safest general-purpose choice.
How long should the trimmer line be when I wind the spool?
Most spools recommend a single piece of line between 15 and 25 feet, depending on the head size. Wind it tightly and evenly in the direction of the arrow, and leave the last 4 to 6 inches loose so the ends can be pushed through the eyelets.
Do I need to disconnect the spark plug before restringing a gas weed eater?
Yes. Disconnect the spark plug wire on gas models, and unplug or remove the battery on electric models, before touching the trimmer head. This prevents the engine from starting accidentally and is the most important safety step in the process.
Why does my new line fly out of the head when I start the trimmer?
This usually means the line was wound in the wrong direction, the spool was installed upside down, or the line ends were not threaded through the eyelets correctly. Disassemble the head, re-check the winding direction arrow, and make sure the line ends are seated in the exit holes before tightening the cap.
