My Weed Wacker String Keeps Breaking (Doing This Fixed It)

Having your weed wacker string break can ruin your whole day, especially if you really need to get those pesky weeds under control! If you notice them breaking repeatedly, it’s time to do something about it. Why do weed wacker strings break in the first place, though?

Weed eater strings break because they become dry and brittle over time. When the damaged string continues to run through the weed eater, the damage amplifies, eventually causing the string to snap. After the string snaps, the weed eater can no longer function as it should.

Thankfully, there are ways to prevent your strings from breaking. In this article, we will cover preventing stings from breaking, what to do if your string breaks and the best ways to install a string in various types of weed trimmers. 

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Here’s a Quick Pro Tip!

Using the correct line in your weed eater makes all the difference when it comes to properly cleaning your yard.  After all, using the wrong line can become expensive, as well as time-consuming.

Consider one of these great options next time you’re looking for a new line:

1. SANJIAN Cordless Weed Wacker: This weed wacker has three different blades to choose from instead of a cord. One is a saw blade that will cut small trees and branches, one for weeds and shrubs, and the other for tender grass and small weeds.

2. Cimekuong Trimmer Line: This line is thickened to last longer and prevent breakage. It is made for medium grass and weed height. It stands out from other cords because the cord is square rather than round and cuts easier. 

3. Anleolife Round Heavy Duty: If you need a weed wacker for heavy-duty work, this cord will help. It is a nylon cord, but it is coated in steel and can cut through thick thorny vines, dense weeds, and thicker plants. 

Broken Strings

There are a few things that will cause a string to break. There are also some great ways to prevent breakage if this keeps happening to you. If this sounds like something you deal with, keep on reading!

Why Does My Trimmer Line Keep Snapping?

There are a few reasons why your trimmer line keeps snapping. One reason is from hitting hard and rough objects like concrete, rocks, and branches the cord is not meant to be used on. It can also be that the feeder is feeding too much cord. 

Another reason is that your cord is of poor quality or only fit for light work. Consumer Reports also warns against weed eaters with a large gap between the trimmer shaft and the cutting head.

Long grass and weeds can get wrapped around the gap and the trimmer line. 

Why is My Weed Eater Line so Brittle?

If your weed eater line is made of nylon, it will eventually become dry and brittle. Nylon is porous and holds water. Soaking it in water occasionally or storing it in water will strengthen the cord. 

It could also seem brittle if the cord is used for heavier work than intended. If you buy a cord that specifies it is for light work, it is meant only to cut tender grass and weeds, not vines or bushes. 

Why Does the Line on my Weed Eater Keep Breaking?

Your line on your weed eater might keep breaking because it is not meant for the level of work you are doing with it. Or it could be dried out. It’s best to store nylon lines in water to prevent breakage. 

It can also be because the weed eater has a gap between the trimmer shaft and the cutting head. If this is the case and you cut tall grass or weeds, they can get tangled in the gap and then around the cord. 

Why Does My Weed Eater String Keep Getting Stuck?

If your weed eater string continually gets stuck, it may be that you did not install the line properly. To install the string,  you can either buy a line on a spool ready to be clicked into place or wrap it yourself in tight and straight lines. 

Another reason the string keeps getting stuck because the spool or spring is broken. Excessive tapping can cause damage to the spool and leave cracks in it.

Springs will lose their effectiveness over time, usually every other year or so, and need to be replaced

Replacing Strings

There are two types of string feeders and two ways to replace the string in them and ways you do not want to replace them. In this section, we will go over all three. Let’s get started!

How to Replace Weed Eater String?

If you have an automatic feeder, you will need a spool with string already wrapped around it and will not need to spin it yourself. However, if you have a bump-feed system, you can remove the reusable spool to wrap the line yourself. 

Bump feeder spools offer more flexibility in changing the line, whereas the automatic spool only feeds more string if the line gets to specific shortness.

However, an automatic spool is more pricey to buy but uses less line over time, so the cost is similar to a bump feeder.  Therefore your choice should come down to preference. 

How Do You Change the String on a Weed Eater?

Bump feed trimmers string needs to be replaced by removing the spool and rewrapping the new line tightly in neat lines around it. An automatic feeder usually uses a pre-spun spool, and you pop out the old spool and line and replace it with a new spool and line. 

Changing the string on an automatic feeder is easier, but you must ensure you buy the correct size for your weed eater.

Most weed eater manufacturers sell the spools that fit the weed eater, and most manufacturers use the same size for most models. 

How Do You Replace the String on a Weed Eater?

To replace the string on an automatic feeder, you will replace the spool and string at the same time. Just clip it off of the weed eater and clip on the next. You must take the reusable spool off for a bump-feed weed eater and manually string the new line. 

The cost of a bump feeder is slightly more than an automatic feeder, but the spool for an automatic feeder is more, and you end up tossing some line when you replace the line and spool.

However, you use less line while weed eating with an automatic feeder. 

How Do You String a Weed Eater?

If you have an automatic line feeder, you just replace the spool with another that’s the same size, and it will be pre-strung. If you have a bump feed trimmer, you will take off the cap on the trimer and string new string on the spool inside the cap. 

For an automatic feeder, it is important to buy the correct size spool replacement. For the bump feeder, it is important to string the line in the direction directed on the spool and to wrap the line tight and straight, so it will not jam. 

How Do You Replace a Trimmer Line?

You can replace a trimmer line in a bump feeder by removing the cap from the head. The cap will have two buttons on the sides. Press both simultaneously and pull the cap off. Within the cap is the trimmer line spool. 

If your weed eater is an auto-feed trimmer, you can replace the spool and the line without restringing the spool.

However, if you have a bump feed, you will need to remove the excess line and wind a new line around the spool in the direction marked. 

How to String a Weed Eater with Two Holes?

Instead of snapping the line in one slot and wrapping the one line around the spool, you will fold the pre-cut line in half, clip the loop in the spool, and wrap the double lines around the spool tightly and in a line. Then you will have two ends to go into two holes. 

A two-hole weed eater is usually a bump feed trimmer, but some are automatic.

If that’s the case, you can still restring it, but you might have to widen the holes for a larger string, and it would be easier to replace both the string and the spool. 

How to Replace the Trimmer Line with a Bump Feed?

Most bump feeder lines are replaced the same way. They usually come off using the two buttons on the side of the spool. The spool also has a button on the bottom, which is what you “bump” to feed more lines. 

Here is the directions step by step:

  1. Remove the spool by pushing the two buttons on the sides of the spool cap simultaneously while pulling the spool off. 
  2. Discard the leftover line, which is on the spool inside the cap. Then, you can easily lift the spool out of the cap.
  3. Measure the new line. The new line should be the width of your body and stretched out arms three times. 
  4. Cut the line. 
  5. Loop the line in the middle and wrap it tightly and straight in the direction marked on the spool.
  6. Snap the end of the line on both sides into the slots in the spool. Then, place the spool in the cap in the same direction. 
  7. Place the cap and spool back onto the weed eater, where it snaps back into place. 
  8. If the length of the line passes the guard of the weed eater, cut it back to where it stays behind the guard.


Weed eaters can be forgiving on the length of the string to an extent, but eventually, if a string is too long, too thick, too short, or too thin, there will be issues.

In this section, we go over what length is best for all of your needs. 

How Long Should the String be on a Weed Eater?

The sting on a weed eater should be 15 to 25 feet in length, depending on the size of the spool. If you do not know the size of the spool or how much you should use for that size, cut more rather than less than you think it will use.

If you use less line than needed, you might have to go through the whole line you cut. But if you cut too much, you just have to cut off the access.

After measuring the string the first couple of times, you will have a better idea of how much to use. 

My Weed Eater is Feeding out too Much Line?

If your weed eater feeds too much line, it could be due to improper line and spool installation. You can check the line on the spool to see if it is wrapped around the spool tightly and in straight lines.

Another common reason for a weed eater to feed too much line is from a faulty spring.

The spring usually only lasts two years or so, and replacing the spring is relatively simple for most weed eater models and inexpensive.  

How Long Should My Weed Eater Line Be?

The length of the line around your spool will depend on the size of your spool, but it will be between 15 to 25 feet long. If you are unsure of the exact amount of line you will need, you can use more than you know you will need and cut off the excess. 

The length of the line outside the spool only needs to be shorter than the width of the weed eater guard. Some weed eater hoods will chop off the excess when you use them.

Additionally, you can measure the line using the length of your arm and body width. 

Does Weed Eater String Size Matter?

The thicker the weed eater string, the longer it will last and the faster it will spin. You can use a thicker string on most weed trimmers, but some thick sizes may not fit. Check your user manual to see which sizes are compatible. 

A thicker string is also for heavier work, and a lighter string is for light work. So, a thicker string may not work if your weed eater is made for light to medium work.

And a thin string on a heavy-duty weed eater may not function well either. 

How Much String Do You Put in a Weed Eater?

How much string you put in a weed eater will depend on the size of the spool, but it will be between 15 to 25 feet in length. Many professional cutters will measure the string length by running it three times the length of their body and arm width. 

If you are unsure of the size of the spool, always cut the line longer and cut off the excess afterward. Otherwise, if the line is cut too short, you may end up throwing out a whole spool. Or you can check with your manufacturer or the spools packaging. 


If the string for your weed eater seems brittle or keeps jamming up, we have the solution.

In this section, we go over common issues and their causes with the weed eater line and what you can do to fix or prevent them. 

How Do You Fix a Weed Eater String?

To fix a weed eater string, you can respin it and soak it in water before reinstalling it. The issue could be dried out and brittle nylon or it could be that you didn’t wrap it tight and straight on the spool. 

It’s also possible the string is too thick or too thin for the spool or weed eater. However, if it fits on the spool and the line fits through the weed eater, there shouldn’t be an issue.

You can even replace the thin string that comes with automatic feeding spools with a thicker one. 

How Long Should a Weed Eater String Last?

On average, if you use a weed eater for 30 minutes weekly, a spool of string will last three months. However, there is no set time for how long until it runs out of line. But if you’ve kept your string for more than a year, you will want to rehydrate it. 

Since weed eater strings do not last long and the tiny bits are scattered into the yard, it is not the most environmentally friendly solution to cutting your weeds.

Birds and other creatures often mistake plastic for food, hurting their indigestion. A weed eater with durable plastic or metal blade is more sustainable and less harmful to the environment. 

Why Won’t the String Pull on My Weed Eater?

When a string on a weed eater doesn’t pull, the spring is usually broken. As a result, springs often need to be replaced every other year or so. Thankfully, replacing the spring is easy and inexpensive. 

Another cause the weed eater string will not pull is from a jam. You can often fix this with a hard tug on the string, but you may need to restring the spool.

If the spool is cracked, that can also cause the string to be jammed. 

How Do You Restring an Automatic Feed Spool?

You can restring an automatic feed spool by looking at how the manufacturer strung the old string. Then, remove the rest of the old string after you are done using it and snap the new string into the spool and wrap it tightly around the spool in lines, not crossing over.

Also, if you want to use a thicker string, you can, but you will need to use pliers or something sharp to widen the holes the string snaps into.

Then you replace the newly strung feeding spool and place it back into the cap and snap the new line in the slot at the bottom of the weed eater. 

You might also enjoy our post on Do Weed Eaters Need Oil?

Related Questions

How Can I Use My Weed Eater for Edging My Lawn?

You can simply turn the trimmer at a 90-degree angle and start trimming. You should keep the trimmer at least one inch above the ground and from any concrete or stones. Always be careful of hitting a rock or other debris. 

When weed eating, especially edging, it is wise to wear protective goggles and gloves. Long pants and tennis shoes or work boots are also suggested.

A weed eater has a shield to protect you from most debris, but if the line catches a rock or other sharp item, it can spin out from the shield and hit you at high speeds. 

How Do You Fix a Broken Weed Eater?

Check your power source if you’re having issues with the weed eater. You may need to check the battery life if you have a battery-operated weed eater. For an electric weed eater, check the cord and the outlet. Lastly, if you have a gas motor, change the fuel. 

If the weed eater starts fine but will not stay on, it could be either a clogged carburetor or an air filter.

You can buy a cleaner for your carburetor while removing the clog. And you can check the user manual for information on changing the air filters.

How Do I Fix an Auto-Feed Trimmer?

The most common issues with an auto-feed trimmer are that the line will not feed properly due to the head being tapped or the trimmer being out of alignment due to the centrifugal force of the system pushing to the line. To fix both, remove any clogs and check the line. 

You might have a clog in an air filter or the carburetor. You could also have an issue with the line and spool installation.

To check the line and the spool, remove the spool from the head and see if the line is still secure in tight straight lines. 

Final Thoughts

We hope this article helps you handle this frustrating issue. Simply changing techniques can help, but buying a better and more reliable product will help too.

Either way, we hope it’s an easy fix for you. 

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