Table of Contents

7 sections 11 min read

Quick Answer: How to Refill a Weed Wacker

To refill a weed wacker (string trimmer), first remove the old line from the trimmer head. Measure and cut a new piece of trimmer line to the correct length and thickness specified in your owner’s manual. Feed the new line through the eyelets or holes in the trimmer head, wind it evenly onto the spool following the directional arrows, and secure it according to the head’s design (bump-feed, fixed-line, etc.). Always ensure the line is properly seated and the spool is reassembled correctly before use.

1
Best Seller

EGO Power+ ME0820 8" Lawn Edger Attachment Kit

EGO Power+
In Stock
9.5 /10
Flagship Score
The Flagship Score evaluates build engineering, verified performance signals, and long-term owner satisfaction.
Updated: Oct 5, 2026
Last update on Oct 5, 2026. Product prices and availability are accurate as of that date/time and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply. Affiliate links / Images, product titles, and product highlights from Amazon.
The EGO Power+ ME0820 is a cordless multi-head edging kit that combines the PH1420 power head with the EA0820 8-inch edger attachment. It is best for EGO 56V users who want a flexible, low-vibration edging setup with broad attachment compatibility.
Pros & Cons

Pros

  • Highly versatile multi-head system with support for a wide range of EGO attachments.
  • Brushless motor and carbon fiber shaft are built for durability and reduced vibration.
  • Edger attachment offers adjustable depth control for more precise curb and driveway edging.
  • Works with EGO 56V ARC Lithium batteries, which is convenient for current EGO users.

Cons

  • Battery and charger are not listed in the kit details, so they may need to be purchased separately.
  • As a multi-head system, it may not be the simplest choice if you only need a basic standalone edger.
  • The product data does not provide weight or runtime, making it harder to compare with other cordless edging options.
Detailed Review

EGO Power+ ME0820 is a cordless multi-head edging kit that pairs the PH1420 power head with the EA0820 8-inch edger attachment. It is designed for homeowners who want one power unit that can support multiple yard-care tasks over time.

The standout feature is flexibility. The power head works with EGO's Multi-Head System attachments, while the edger itself offers up to 3 inches of depth adjustment for crisp lawn borders. A brushless motor, digital two-speed control, and IPX4 weather-resistant construction add practical value for regular outdoor use.

There are a few limitations to consider. The kit details do not include a battery or charger, so some buyers may need to add those separately. It is also best suited to users already invested in the EGO 56V platform, since the system's value is strongest when paired with other compatible attachments.

Overall, this is a strong option for EGO owners who want a durable, expandable edging system rather than a single-purpose tool. It should appeal most to users who value modularity, cleaner edging control, and compatibility with a larger cordless yard-care lineup.

2
Editor's Pick

RYOBI ONE+ 18V 13 in. Cordless String

RYOBI
In Stock
9.5 /10
Flagship Score
The Flagship Score evaluates build engineering, verified performance signals, and long-term owner satisfaction.
Updated: Oct 5, 2026
Last update on Oct 5, 2026. Product prices and availability are accurate as of that date/time and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply. Affiliate links / Images, product titles, and product highlights from Amazon.
The RYOBI ONE+ 18V 13 in. Cordless Battery String Trimmer/Edger is a lightweight 2-in-1 tool for trimming and edging small to medium lawns, with a pivoting head, variable-speed trigger, adjustable 11 in. to 13 in. cut width, and included battery and charger.
Pros & Cons

Pros

  • Includes both battery and charger for immediate setup.
  • Compatible with RYOBI 18V ONE+ batteries for broader system flexibility.
  • Lightweight design improves portability and reduces fatigue during regular yard work.
  • Supports both .065 and .080 trimmer line for added line compatibility.

Cons

  • 13-inch maximum cutting width is more suited to small and medium yards than large properties.
  • No runtime, noise level, or weight spec is provided in the source data.
  • The product details do not specify advanced features such as brushless motor technology or telescoping shaft adjustment.
Detailed Review

Overview: The RYOBI ONE+ 18V 13 in. Cordless Battery String Trimmer/Edger is a lightweight, battery-powered lawn tool designed for basic trimming and edging tasks. Its 2-in-1 setup makes it a practical option for homeowners who want one tool for routine yard cleanup.

Performance: A pivoting head helps the tool transition into edging mode, while the variable-speed trigger gives the user more control over light trimming and tougher spots. The adjustable 11 in. to 13 in. cutting width adds flexibility, and compatibility with .065 and .080 line makes replacement easier.

Drawbacks: This model is best matched to smaller or medium-size yards because its 13-inch cutting width is modest. The provided data does not list runtime, total weight, or advanced motor details, so buyers should avoid assuming high-end performance beyond the stated features.

Verdict: For homeowners already using the RYOBI ONE+ platform, this trimmer/edger offers convenient cordless operation and broad battery compatibility. It is a sensible pick for straightforward lawn maintenance, especially when included battery and charger value matters.

3
Limited Time

WORX WG163 20V Cordless 12" String Trimmer & Lawn

WORX
In Stock
9.5 /10
Flagship Score
The Flagship Score evaluates build engineering, verified performance signals, and long-term owner satisfaction.
Updated: Oct 3, 2026
Last update on Oct 3, 2026. Product prices and availability are accurate as of that date/time and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply. Affiliate links / Images, product titles, and product highlights from Amazon.
The WORX WG163 is a lightweight 20V cordless string trimmer and lawn edger designed for homeowners, offering seamless 2-in-1 conversion, command feed system, and two included batteries for versatile yard maintenance.
Pros & Cons

Pros

  • True 2-in-1 design that converts quickly between trimmer and edger modes
  • Command feed spool with free spools for life program for ongoing convenience
  • Two 20V batteries and charger included for extended use out of the box
  • Tilting head plus rubberized wheels improve control on varied terrain
  • Full Power Share compatibility with other WORX 20V and 40V tools

Cons

  • 12-inch cutting diameter may require extra passes on larger lawns
  • 0.065-inch line diameter best suited to light and medium grass rather than heavy brush
  • Battery-powered design means runtime depends on charge levels without specified duration
Detailed Review

The WORX WG163 is a cordless 20V string trimmer and lawn edger built for residential use. Weighing just 5.5 lbs with a compact design, it features rubberized wheels and an adjustable spacer guard that create a solid first impression of a user-friendly outdoor power tool focused on precision and ease.

In performance the 7600 rpm motor and 12 inch cutting diameter handle standard grass trimming effectively. The innovative command feed allows instant line deployment with a push button while the head tilts up to 90 degrees for slopes and tight spaces. Conversion from trimmer to edger takes only seconds and the two included Power Share batteries support the broader WORX ecosystem for ongoing convenience.

Potential drawbacks include the 12 inch path that can slow progress on expansive lawns and the 0.065 inch line suited mainly to lighter tasks. Battery runtime is not detailed in specs so users may need to plan around recharges for prolonged sessions.

Overall the WORX WG163 delivers strong value for homeowners managing small to medium yards who want a convertible cordless tool with ecosystem compatibility and straightforward operation.

Understanding How a Weed Wacker Head Works

Cross-section comparison of bump-feed and fixed-line trimmer head mechanisms

Before diving into the refill process, it helps to understand the mechanism you’re working with. The trimmer head is the rotating component at the end of the shaft that holds and dispenses the cutting line. As the head spins at high speed, centrifugal force stiffens the line, allowing it to slice through grass and weeds.

Bump-Feed vs. Fixed-Line Heads

There are two primary types of trimmer heads, and the refill process differs slightly for each: Users looking for related component recommendations can explore our jbl partybox club 120 vs sony srs xv500 breakdown.

  • Bump-feed heads (also called semi-automatic): These contain a spool wound with a continuous length of line. When the line wears down, you tap the head on the ground while the engine is running, which releases a spring-loaded mechanism that feeds out more line. This is the most common type on residential and commercial trimmers.
  • Fixed-line heads: These use individual pre-cut lengths of line that are inserted into slots or holes on the head. When a piece breaks or wears out, you simply insert a new segment. These are faster to reload but require keeping pre-cut pieces on hand.

Why Trimmer Line Wears Down

Trimmer line gradually shortens through normal use as it contacts vegetation, hard surfaces (sidewalks, curbs, fences), and debris. The line’s tip frays and breaks off, reducing cutting efficiency. Heat from friction can also weaken the line over time. Regular refilling maintains optimal cutting width and reduces strain on the trimmer’s motor. Users looking for related component recommendations can explore our jbl partybox club 120 vs sony srs xv500 breakdown.

Choosing the Correct Trimmer Line

Using the wrong line diameter or type is the most common cause of feeding problems, excessive breakage, and poor cutting performance. Always consult your owner’s manual for the manufacturer’s specifications.

Line Diameter: What the Numbers Mean

Trimmer line diameter is measured in inches (e.g., 0.065, 0.080, 0.095, 0.105, 0.130, 0.155). The larger the number, the thicker and more durable the line: Before finalizing equipment decisions, refer to our comprehensive z890 vs x870e motherboard comparison.

Diameter Best For Typical Trimmer Power
0.065″ – 0.080″ Light grass, edging, small electric/battery trimmers Under 25cc gas / 20V–40V battery
0.085″ – 0.105″ General residential use, thicker weeds, mixed grass 25cc–35cc gas / 40V–60V battery
0.110″ – 0.130″ Heavy weeds, brush, commercial use 35cc+ gas / high-voltage pro battery
0.155″+ Thick brush, saplings, dedicated brush cutters Professional gas brush cutters

Critical: Never use line thicker than your trimmer head’s maximum rating. Oversized line won’t feed properly, can jam the mechanism, and may overheat the motor.

Line Shape and Profile

The cross-sectional shape affects cutting efficiency and line life: For broader ecosystem context, read through our operational guide on marshall stanmore iii vs harman kardon onyx studio 8.

  • Round: Most common, durable, quiet, good for general grass. Tends to tear rather than slice thick stems.
  • Square / Multi-sided: Sharp edges cut cleaner through thick weeds and brush. Wears faster on concrete/asphalt. Louder than round.
  • Serrated / Saw-tooth: Aggressive cutting for heavy vegetation. Shorter lifespan, noisier.
  • Twisted / Spiral: Reduces drag and noise, improves feed consistency. Good all-around choice.
  • Star / Cross / Diamond: Multiple cutting edges for heavy-duty work. Faster wear on abrasive surfaces.

Pro tip: For most homeowners, a twisted or square line in the manufacturer’s recommended diameter offers the best balance of cutting speed, line life, and feed reliability.

  1. Check the owner’s manual (often available as a PDF on the manufacturer’s website if lost).
  2. Look for a sticker on the trimmer head or shaft housing.
  3. Search the model number + “trimmer line size” online.
  4. When in doubt, take the old spool or a sample of the old line to a hardware store for matching.

Step-by-Step Guide to Refilling Your Weed Wacker

Safety first: Before starting, ensure the trimmer is completely powered off. For gas models, disconnect the spark plug wire. For electric/battery models, unplug or remove the battery. Wear gloves to protect your hands from sharp line ends and any debris on the head.

Step 1: Remove the Trimmer Head / Spool

The removal method depends on your head design: For troubleshooting and reliability insights, consult our in-depth dyson v8 cyclone vs bissell featherweight stick report.

  • Bump-feed (most common): Hold the outer head housing steady and unscrew the knob or bump cap on the bottom (usually counterclockwise). Some models have tabs you squeeze to release the cover. Lift off the cover and remove the inner spool.
  • Fixed-line: The head may not disassemble. You simply pull out the old line segments from the external slots.
  • Quick-load / rapid-load heads: These often have a single-piece design where you thread line through external ports without removing a spool. Consult your manual for the specific release mechanism.

Step 2: Clean the Head and Inspect for Damage

Remove any grass clippings, dirt, or tangled old line from the spool and head housing. Check the eyelets (the holes where line exits) for wear—sharp or cracked eyelets will shred new line quickly. Inspect the spring and feed mechanism on bump-feed heads; clean out debris and ensure the spring moves freely.

Step 3: Measure and Cut New Line

For bump-feed spools: Most residential spools take 10–25 feet of line. Check your manual for the exact length. If unspecified, a good rule of thumb is to wind line until the spool is about 80–90% full—don’t overfill, or the line won’t feed properly. Cut the line cleanly with scissors or a utility knife. Readers comparing setup options can review our technical analysis on bissell crosswave hydrosteam vs shark stainforce.

For fixed-line heads: Cut individual pieces to the length specified in the manual (typically 8–12 inches). Cut several pieces at once so you have spares ready.

Step 4: Thread and Wind the Line (Bump-Feed Spool)

  1. Find the anchor point: Look for a small hole, notch, or slot in the spool’s center hub. This is where the line starts.
  2. Insert the line: Push one end of the line into the anchor hole until it catches. Some spools have two anchor points for dual-line winding—insert both ends if so.
  3. Wind in the correct direction: Look for an arrow on the spool indicating wind direction (usually counterclockwise when viewing the spool from the bottom). Wind neatly, layer by layer, keeping tension on the line so it sits tight. Avoid crossing lines or creating gaps.
  4. Leave the tails: Stop winding when you have about 6–8 inches of line remaining. Secure the loose end in the spool’s temporary holding notch or slot (designed to keep the line from unraveling during reassembly).
  5. Dual-line spools: If your spool has two separate winding chambers (divided by a center flange), wind one length in each chamber, starting both at their respective anchor points. Keep the lines separated.

Step 5: Install Pre-Cut Segments (Fixed-Line Head)

  1. Take a pre-cut piece of line and fold it in half to find the center (or insert one end first, depending on head design).
  2. Push the line through the eyelet from the outside until the center bend catches inside the head, or insert both ends into opposing slots.
  3. Pull firmly to seat the line securely. Repeat for all slots (typically 2–4 lines total).

Step 6: Reassemble the Head

  1. Place the spool back into the head housing, aligning any notches or tabs.
  2. Feed the loose line tails through the eyelets in the outer housing. This can be tricky—use needle-nose pliers if needed to pull the line through.
  3. Replace the bump cap / cover and screw it on securely (clockwise). Ensure it clicks or seats fully.
  4. Pull gently on the line tails to verify they’re free to move and not pinched.

Step 7: Test the Trimmer

Reconnect power (spark plug wire, battery, or cord). Start the trimmer and let it reach full speed. For bump-feed heads, tap the head lightly on grass (not concrete) to advance the line. The line should extend and the built-in cutter blade on the guard should trim it to the correct length. If the line doesn’t feed, see the troubleshooting section below.

Troubleshooting Common Refill Issues

Problem: New Line Keeps Tangling or Jamming in the Head

Causes & fixes:

  • Wound in wrong direction: Rewind following the arrow on the spool.
  • Overfilled spool: Remove some line—leave at least 1/8″ gap between line and spool flange.
  • Line crossed or loose: Rewind with consistent tension, no crossing layers.
  • Wrong diameter: Verify line matches spec; oversized line jams in eyelets.
  • Damaged eyelets: Replace the head housing if eyelets are grooved or sharp.

Problem: Line Won’t Feed When Bumping the Head

Causes & fixes:

  • Line welded to itself: Heat from high-speed use can fuse nylon layers. Always wind loosely enough that layers don’t bond. If fused, discard and rewind fresh line.
  • Spring mechanism stuck: Disassemble, clean debris from spring and spindle, lubricate lightly with silicone spray (not oil—oil attracts dirt).
  • Line too short: Bump-feed needs enough centrifugal force to overcome spring tension. Ensure at least 3–4 inches of line extends past the eyelet.
  • Cap overtightened: Loosen the bump cap slightly; it should spin freely.

Problem: Line Breaks Immediately Upon Use

Causes & fixes:

  • Line too thin for the job: Step up one diameter size (e.g., 0.080″ → 0.095″).
  • Hitting hard surfaces: Avoid contact with concrete, rocks, metal edging. Use a slower speed near obstacles.
  • Old/brittle line: Nylon degrades with UV exposure and age. Buy fresh line; store in a sealed bag away from sunlight.
  • Wrong line shape: Switch from serrated/square to round or twisted for better impact resistance.
  • Eyelet damage: Sharp edges on worn eyelets act like razors. Replace head housing.

Problem: Line Feeds Out Too Much / Won’t Stop Feeding

Causes & fixes:

  • Spring weak or broken: Replace the spring (inexpensive, available at repair shops).
  • Line not anchored properly: Ensure line is fully seated in the spool’s anchor hole/notch.
  • Worn feed mechanism: The pawl or ratchet inside the head may be worn. Replace the head assembly.

Pro Tips for Easier Refills and Longer Line Life

  • Soak line in water overnight before winding—nylon absorbs moisture, becoming more flexible and less prone to welding/brittleness.
  • Buy line in bulk spools (1 lb or 3 lb) rather than small cards—far cheaper per foot and you can cut exact lengths.
  • Keep a spare pre-wound spool ready to swap for zero-downtime refills mid-job.
  • Use the line cutter on the guard—don’t let line get too long, which increases drag and breakage.
  • Match line to vegetation: Keep a spool of heavier square line for brush days, lighter round line for weekly lawn edging.
  • Clean the head after each use—compressed air or a brush prevents grass buildup that jams the feed mechanism.

Common Questions on How To Refill A Weed Wacker Answered

How often should I refill my weed wacker line?

Refill when the line wears down to about half its original length or when cutting efficiency noticeably drops. For average residential use, this might be every 1–3 mowing sessions. Heavy brush clearing can consume a full spool in one session.

Can I use any brand of trimmer line in my weed wacker?

Yes, as long as the diameter and shape match your trimmer’s specifications. Brand compatibility is not an issue—line is a universal consumable. However, quality varies; name-brand lines (Oregon, Stihl, Husqvarna, Echo, Arnold) tend to have more consistent diameter and better nylon formulations than generic bulk line.

Why does my trimmer line keep getting stuck inside the head?

This is usually caused by winding the line in the wrong direction, overfilling the spool, or using line that’s too thick for the head’s eyelets. It can also happen if the line melts and fuses to itself from heat—always wind with slight tension and don’t overfill. Soaking line in water before winding helps prevent fusion.

Is it better to buy pre-cut line pieces or a bulk spool?

Bulk spools are significantly more economical (often 5–10x cheaper per foot) and let you cut exact lengths for your specific spool. Pre-cut pieces are convenient for fixed-line heads but cost more. For bump-feed heads, bulk spools are the clear winner.

Can I refill a weed wacker while the engine is running?

Absolutely not. Always power off completely (disconnect spark plug, remove battery, or unplug) before servicing the trimmer head. The spinning head can cause severe lacerations, and the engine can start unexpectedly if the spark plug is connected.

For more hands-on benchmarks and buying recommendations, consult our guides on residential zero-turn lawn mower guide, as well as automated robotic lawn mower guide.

Mechanical safety standards, operational tolerances, and protective gear guidelines align with benchmark specifications established by the American National Standards Institute (ANSI).