Why does my trimmer line keep breaking off short?

Usually the line is wound too tightly or has developed a memory kink from sitting unused, causing it to snap rather than feed smoothly. It can also happen if the line is the wrong diameter for the head, or if it's old and has become brittle from UV exposure or age. Rewinding fresh line properly, without overlapping wraps, generally resolves this.

Why won't my auto-feed head advance line at all?

Auto-feed heads rely on centrifugal force or a bump mechanism to release a small amount of line each cycle. If the line is tangled, cross-wound, or wound too tightly around the spool, it can bind and prevent feeding. A stripped or worn bump-feed spring is a less common but possible cause on bump-feed heads specifically.

How do I properly rewind trimmer line without it tangling?

Wind the line onto the spool in the direction indicated by the arrow molded into the spool, keeping each wrap snug against the previous one without overlapping. Overlapping wraps are the most common cause of a line jam, since the line crosses over itself and binds when the head tries to release it.

Is it better to replace the line or the whole spool assembly?

Replacing just the line is cheaper and sufficient in most cases. If the spool housing itself is cracked, the feed mechanism spring has failed, or the eyelets the line passes through are worn to a sharp edge that keeps cutting new line, replacing the full spool assembly is the more reliable fix.

String Trimmer Line Not Feeding: 6 Causes and Fixes

If your string trimmer's line won't advance, jams in the head, or keeps breaking off short, the cause is usually one of a handful of common issues. Here are the 6 most likely causes and how to fix each one.

Step-by-Step Guide

Fix 1: Check for tangled or overlapping line

Remove the spool and inspect how the line is wound. Overlapping or crossed wraps are the most common cause of a jam. Unwind the line fully and rewind it in the direction shown on the spool, keeping each wrap snug and flat against the last.

Fix 2: Confirm you're using the correct line diameter

Check your trimmer's manual or the spool housing for the maximum line diameter it accepts. Line that's too thick for the head can jam the feed mechanism or fail to release properly. Most consumer trimmers accept 0.065 to 0.095-inch line, confirm before installing a thicker gauge.

Fix 3: Clean debris from the spool housing

Grass clippings, dirt, and plant matter can pack into the spool housing over time and block the feed mechanism. Remove the spool, clear out visible debris with a brush or compressed air, and check that the internal feed holes or slots are clear before reassembling.

Fix 4: Inspect the line for age-related brittleness

Trimmer line that's been sitting unused for a season or more, especially in direct sun, can become brittle and snap rather than feed. If the line breaks repeatedly at short lengths despite being wound correctly, replace it with fresh line.

Fix 5: Check the bump-feed mechanism, on bump-feed heads

If your head uses a bump-feed system (tapping the head on the ground to release line), inspect the internal spring and release mechanism for wear or a stuck component. A spring that's lost tension won't release line consistently even when tapped correctly.

Fix 6: Replace the spool assembly if the housing is damaged

A cracked spool housing, worn eyelets, or a failed auto-feed sensor mechanism generally can't be fixed by rewinding line alone. Replacement spool assemblies are inexpensive and widely available for most trimmer models, and swapping the whole unit resolves persistent feeding issues faster than repeated troubleshooting.

A trimmer that won't feed line mid-job is one of the most common frustrations in this category, and it's almost always fixable without a repair shop.

Most feeding problems come down to how the line is wound, whether it's the right diameter for the head, or debris that's worked its way into the spool housing.

Auto-feed heads, like EGO's POWERLOAD or the dual-feed systems on Greenworks and Worx trimmers, are generally more forgiving than manual bump-feed heads, but they can still jam if the line is wound incorrectly or the housing gets packed with debris.

Work through the fixes below roughly in order, starting with the most common cause before moving to a full spool replacement.

Start With the Basics

Check the wind direction and pattern: most feeding issues trace back to overlapping or crossed line wraps. Rewind following the arrow on the spool, keeping wraps flat and snug.

Confirm line diameter: using line thicker than the head is rated for is a common but easily overlooked cause of jamming.

Clear visible debris: grass and dirt packed into the housing block the feed path even when the line itself is wound correctly.

Diagnosing Your Specific Problem

Line breaks off short repeatedly: likely old, brittle line or a wind pattern that's putting too much tension on the line as it feeds. Replace with fresh line and rewind carefully.

Line won't advance at all, even after bumping or pressing the feed button: check for tangled or overlapped wraps first, then inspect the feed mechanism itself for a stuck or worn component.

Line feeds unevenly, too much or too little at a time: usually a sign of inconsistent winding tension or a partially worn feed spring on bump-feed heads.

Line was feeding fine, then suddenly stopped: most likely new debris has packed into the housing, or the line has developed a kink or tangle during recent use. Inspect and clean before assuming a mechanical failure.

Quick Diagnosis

Symptom	Most Likely Cause	Fix
Line breaks off short	Old, brittle line or incorrect winding	Replace line, rewind carefully
Won't feed at all	Tangled or overlapped wraps	Unwind and rewind following the spool arrow
Feeds inconsistently	Debris in housing or worn feed spring	Clean housing, inspect spring
Worked before, stopped suddenly	Fresh debris or a new tangle	Clean and inspect the spool
Auto-feed button does nothing	Jammed feed mechanism	Remove spool, clear obstruction, reinstall