Your Grass Trimmer Line Is Worn Out: What Now?
You’re halfway through edging your lawn when the familiar buzz of your string trimmer suddenly loses its bite. Instead of slicing through overgrown grass, it’s just pushing it around. You look down and see the nylon line has worn down to a nub, or maybe it snapped off completely.
This moment is a universal rite of passage for anyone who maintains a yard. Knowing how to change grass trimmer line is an essential skill that saves you time, money, and frustration. You could pack up the tool and head to the repair shop, but that means waiting days and paying for a simple fix.
The truth is, replacing trimmer line is a straightforward five-minute job once you understand the system. This guide will walk you through the entire process, from identifying your trimmer head type to winding the new line correctly, ensuring you get back to a perfectly manicured lawn edge quickly.
Understanding Your Trimmer’s Feeding System
Before you buy new line or start taking things apart, you need to know what kind of trimmer head you have. The replacement process differs significantly between the two main types.
Bump Feed Trimmer Heads
This is the most common system on homeowner-grade gas and electric trimmers. To release more line, you gently tap or “bump” the head on the ground while the trimmer is running. The head contains a spool of line that advances incrementally with each bump.
To refill it, you must open the head, remove the old spool, wind new line onto it, and reassemble everything. It’s a manual process but offers good control over line length.
Automatic Feed Trimmer Heads
These heads, often labeled “Auto-Feed” or “Easy-Feed,” advance the line automatically when the throttle is released and then reapplied. They sense when line is short and feed out more without requiring you to bump the head.
The refill process is usually simpler. You often just feed pre-cut lengths of line directly into the eyelets on the head until they click into place, with no spool winding required. Always check your manual, as the exact method varies by brand.
Gathering the Right Tools and Materials
You only need a few items to complete this job. Having them ready before you start makes the process smooth.
– The Correct Trimmer Line: This is critical. Check your trimmer’s manual for the recommended line diameter (common sizes are .065″, .080″, .095″, or .105″). Using line that’s too thick can jam the head; line that’s too thin will wear out and snap instantly.
– Safety Gloves: Nylon line can have sharp ends when cut. A pair of sturdy work gloves protects your hands.
– Safety Glasses: Always wear eye protection when working with tools, even during maintenance.
– Needle-Nose Pliers: Useful for pulling out old line remnants or helping to thread new line.
– Scissors or a Utility Knife: For cutting the new line to the proper length.
– A Clean Workspace: A bench or sturdy table is ideal. Lay down a rag to catch any small parts.
Step-by-Step: Changing Line on a Bump Feed Trimmer
Follow these steps carefully. If you get stuck, pause and consult your trimmer’s specific manual.
Removing the Trimmer Head
First, ensure the trimmer is completely off and disconnected from power (unplug electric models, remove the spark plug wire on gas models). Hold the head steady. Look at the center. Many heads have a locking button or two holes for a pin or Allen key. Depress the button or insert the tool to lock the spindle, then turn the entire head counterclockwise (lefty-loosey) to unscrew it from the drive shaft.
Some older models may have a reverse-thread. If the head won’t budge, check the manual. Once loose, lift the head assembly off the trimmer.
Opening the Head and Removing the Old Spool
Place the head on your work surface. The top cover usually snaps or screws onto the base. Look for tabs or notches. Press the tabs or turn the cover to unlock it, then lift it off. Inside, you’ll see the spool with two short ends of line.
Lift the spool out. It may be wound with old line. If the line is brittle or broken, unwind it all and discard it. Take a moment to clean any grass, dirt, or debris from inside the head housing with a brush or rag.
Winding the New Line onto the Spool
Find the center of the spool. There is usually an arrow or the word “Wind” indicating the direction to wind the line. This direction is crucial. If you wind it the wrong way, the bump feed mechanism will not work.
Take your new line. Most spools have two separate channels or holes to start the line. Feed about 6 inches of line into one of the anchor holes on the spool. Now, wind the line neatly and tightly onto the spool in the direction of the arrow. Keep the lines parallel and avoid overlapping or crossing them.
Leave about 6 inches of line unwound when you’re done. Repeat the process for the second channel, winding in the same direction. You should now have two 6-inch tails of line protruding from the spool.
Reassembling the Head
Place the spool back into the head housing. Carefully pull each line tail out through its respective eyelet or notch on the side of the housing. Ensure the lines aren’t tangled. They should slide out freely.
Now, place the top cover back on. Align any tabs or arrows. You may need to push and turn slightly until it clicks or locks into place. The lines will now be trapped between the cover and the base, held securely.
Reattaching the Head to the Trimmer
Thread the head back onto the drive shaft. Hand-tighten it clockwise until it’s snug. Do not overtighten. Reconnect your power source (plug or spark plug wire).
Before starting the trimmer, pull on both lines to ensure they feed smoothly. You may need to give them a firm tug to release them from the locking mechanism inside the head. They should extend to an even length, typically 6-8 inches. Use your scissors to trim the ends to a point if they are blunt; this improves cutting efficiency.
Step-by-Step: Changing Line on an Automatic Feed Trimmer
The process for automatic heads is often quicker, as there’s no spool to wind.
First, power down and secure the trimmer. Identify the line entry points or eyelets on the head. These heads typically use two short, pre-cut lengths of line.
Take one piece of your approved line. Feed it into one of the eyelets, pushing it inward until you feel or hear it click into the internal gripping mechanism. Pull gently on the outside end to confirm it’s locked. Repeat for the second eyelet.
Pull on both lines from the outside until an equal amount extends from the head, usually around 6-8 inches. Trim the ends to a point. That’s it. The internal mechanism will handle the rest during use.
Troubleshooting Common Line Replacement Problems
Even with careful work, you might encounter a hiccup. Here’s how to solve frequent issues.
The Line Won’t Feed When Bumping
If you’ve reassembled a bump feed head and tapping does nothing, the line is likely wound in the wrong direction. The head’s internal spring only engages when line is pulled in the winding direction. Disassemble, unwind the line, and re-wind it following the arrow on the spool precisely.
Another cause could be the lines are tangled inside the head or caught under the spool. Reopen the head and ensure the lines are seated correctly in their channels and exit cleanly through the eyelets.
The Line Keeps Breaking Immediately
Constant breakage usually points to the wrong line diameter. Verify you’re using the exact size specified for your trimmer. Also, avoid trimming against hard surfaces like rocks, concrete curbs, or fence posts. This abrades the line rapidly. Use the tip of the line for cutting, not the full length.
Old, brittle line that’s been stored in a shed for years can also snap easily. Use fresh line from a sealed package.
The Head Jams or Won’t Spin
This serious issue often occurs if line is wound too loosely or overlaps on the spool. The loose coils can spill out and bind the mechanism. It can also happen if you’ve forced line that’s too thick into the head. Disassemble immediately, remove all line, and start over with the correct size, winding tightly and neatly.
Pro Tips for Longer Lasting Trimmer Line
A few simple habits can make your line last much longer, saving you time and money on replacements.
– Sharpen the Ends: Each time you bump out new line, quickly tap the ends on concrete or use scissors to cut them at a sharp angle. A pointed tip cuts more efficiently than a blunt, melted end.
– Use the Right Line for the Job: For simple grass, standard round nylon line is fine. For thicker weeds, consider twisted line or line with a square or star shape, which offers more cutting surface. For heavy brush, some trimmers can use plastic blades.
– Avoid Hard Surfaces: Be mindful when edging along driveways or sidewalks. Let the string *hover* just above the concrete to cut the grass overhang without grinding the line down.
– Store Line Properly: Keep unused trimmer line in its original package in a cool, dry place out of direct sunlight. UV exposure weakens nylon over time.
Mastering This Essential Maintenance Task
Changing your grass trimmer line is not a complex repair; it’s basic, routine upkeep. By taking twenty minutes to learn your specific tool, you gain independence and keep your landscaping on schedule. No more waiting for appointments or paying for simple service calls.
The key takeaways are simple: identify your head type, use the manufacturer-specified line diameter, wind in the correct direction for bump heads, and always prioritize safety by disconnecting power. With this knowledge, a worn-out line becomes a minor pause in your yard work, not a project-stopping problem.
Your next step is to locate your trimmer’s manual, check the line specification, and pick up a spool from your local hardware store. Then, the next time your trimmer loses its edge, you’ll be ready to restore its cutting power in minutes and get back to the satisfying work of perfecting your lawn’s borders.
