Why Does My Trimmer Line Keep Coming Out?

The trickiest part of using a string trimmer is managing the line inside. Your trimmer line can regularly create issues for you for various reasons. Plenty of people ask why their trimmer lines come out, for example. So what are the reasons behind your trimmer line coming out?

Your trimmer line is coming out because of 3 possible issues: 

  • The head may be faulty, so it has broken or worn-out components that disrupt its functioning.
  • The spool you wrap your line around can be damaged, or you’re winding the wires incorrectly. 
  • You might be using the wrong line for your trimmer model.

There can be numerous things going on with your trimmer, especially if it’s old. But there are some tell-tale signs of why your trimmer string won’t stay put. Keep reading this article to find out why your weed trimmer’s string keeps coming out and how you can fix it.

3 Reasons Why Trimmer Lines Come Out

There can be a list of things going wrong if your trimmer line isn’t staying put. If you’ve ruled out cases such as the trimmer being broken, trimmer line snapping, and other nonspecific issues, then that makes identifying the problem easier. 

Here are 3 points in particular that you can look out for:

1. Faulty Head 

The head of the trimmer can be the culprit for many reasons.

Firstly, since the head is made of multiple attachments, any of them malfunctioning will cause poor performance. These parts breaking or losing placement can make your string unwind from its position. 

One example is the head spring, which can accidentally be installed too tight or loosen after high-speed functioning. Both can cause overfeeding.

Secondly, just like the string is meant to be within a size range recommended for your trimmer, the head cap also has a size requirement. 

If you’ve recently replaced yours, that could be why you’re facing all kinds of line issues, such as tangles, breakage, and the line coming out when you don’t want it to. Always make sure that the replacement trimmer head is the same size that originally came with your weed eater. 

Lastly, your head cap may be old. If it’s been on for a few years, it could very well be worn out by now. The damage can be external, which may be visible to you as cracks. Or internal, where the tabs inside that lock the cap into place are broken. 

Wear and tear is the leading cause here, but going in too hard is also responsible if there’s premature breakage.

If you have to replace your trimmer head, don’t be alarmed – the process is pretty straightforward for most models. Check out this video to see how it’s done: 

Obviously, the video is about a Stihl trimmer so the process can be slightly different for other brands. I just wanted to show you how easy it is in most cases. 

And if you don’t feel like dealing with the replacement, your local repair shop can also do it for you for a fee. 

Consider Getting a Repair Manual

Repair manuals are often released by the manufacturer itself to guide repair professionals in troubleshooting and fixing their equipment. As you can imagine, they are pretty helpful when you aren’t sure what the problem is or how to perform a specific task. 

So if you want to fix your equipment yourself, getting one of these can be a good option especially if you intend to use your tool for a long time as these guides can help you troubleshoot the most common malfunctions, not just the one you are dealing with right now. 

A good site to look for these is emanualonline.com – they have over 2,5 million repair manuals available, so there is a good chance they have one for yours too. Just make sure you get the one for your specific model!

2. Improper Spool or Winding

The spool is another component found in the trimmer head. This is the part you secure and wrap your line in.

Here there can be two scenarios: 

  1. The spool isn’t suitable for your trimmer. 
  2. You’re not winding the line properly around the spool.


First and foremost, check if your spool is damaged or unusable because of wear down. If it is, you’ve gotten to the bottom of it. Then, you can think about a replacement. If you’ve already replaced the spool recently, you can think about this too. 

Spools have different sizes, too. If it’s too large or too tight for your trimmer, it will come undone in both instances.

Just know that nobody’s judging your winding skills. It’s an innocent learning curve; everyone’s been there. 

The proper way to wrap your line is by making small hooks at one end, getting it stuck in openings on the spool, and winding it in a clockwise direction. 

If you aren’t sure how to do it, here is a pretty good video that can show you the process: 

Practice as often as you can to perfect the art.

3. You’re Using the Wrong Line

The trimmer’s line is essential to its efficient performance. Many factors are coming into play here; the size of the string, the shape, or the material quality all impact the trimmer.

Thanks to most trimmer manufacturers, the string sizes are easy to figure out. Each trimmer has a recommended range of width you can use as a guide. 

If the line is on the lower end of the spectrum, it’ll break loose. If it’s beyond the range, it might get stuck and eventually come undone once you put pressure on it.

Trimmer strings in a store
With an abundance of available trimmer line sizes and designs, it isn’t always easy to pick the right one.

The shapes and materials come down to personal preference or brands available on the market. 

Round or twisted lines usually work best for trimmers, giving a smooth operating experience. Other shapes might work well depending on the material quality. Premium or well-known brands have great options in all kinds of lines; trust them over cheap picks.

If you are having problems choosing the right trimmer string, check out this article where I talk about this topic in greater detail.


How Do I Stop My Trimmer From Auto Feeding?

To troubleshoot or fix your trimmer’s automatic feeding mechanism, you need to check if any line is overlapping or is crisscrossed. Begin by taking the trimmer head off. Then clean the trimmer’s spool and the inside of the head with a cloth. 

Ensure there aren’t any cracks or holes in the trimmer spool. A damaged spool or line won’t spin properly and can halt the automatic feeding system from working properly.

How Do You Restring an Automatic Feed Spool?

To restring an automatic feed spool, start by taking a few inches of line out from the spool. Then put the line through the feeding hole carefully. Ensure there’s at least 4 to 5 inches of line available on the outside of the barrel.

Finally, put your spool on the barrel and cover it with its cap. After that, snap the wire into place. The entire process takes around 2 minutes and then you can get back to trimming your lawn!

Final Thoughts

Overfeeding is a hurdle you have to face from time to time, one way or another. If you diligently replace components, like your trimmer head cap and head spring, you can definitely lower its occurrence. On top of that, make sure you pick the right line and spool for your trimmer. You’ll need a lot of practice to wind your trimmer string properly, but you’ll get there soon!

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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