Tools & Materials
String trimmer out of whack? It's time to face the fix. Whether you are a legendary landscaper or a weekend weed whacker, eReplacementParts.com provides the parts, procedures and facts you need to fearlessly fix what fails you.
The plunger spring (also known as the spool spring) is one of the components in the trimmer head that allows the unit to automatically feed line. When the bump head is bumped against the ground, the plunger pushes against the spring, which activates the slider, and fresh line is fed from the spool.
Over time, the plunger spring can weaken or break, causing the feeder assembly to malfunction. Replacing the plunger spring is very easy to do.
This article provides step-by-step instructions for removing and installing the plunger spring on a Ryobi trimmer.
Let's get started.
REMOVING THE PLUNGER SPRING [top] 1. Remove the reel and line assembly.
Unscrew (and remove) the bump head knob.
Remove the reel and line assembly.
2. Remove the plunger spring.
Use a pick or small screwdriver to disengage (and remove) the C-clip from the shaft.
Remove the plunger.
Remove the plunger spring.
INSTALLING THE NEW PLUNGER SPRING [top] 3. Install the plunger spring.
Install the new plunger spring onto the shaft.
Install the plunger onto the shaft. Note that the angled edges of the plunger should align with the angled edges of the slider.
Depress the plunger against the slider until the groove for the C-clip becomes visible on the metal shaft.
Use long-nosed pliers to install the C-clip into the groove on the metal shaft (and secure the plunger).
REASSEMBLING THE UNIT [top] 4. Reinstall the reel and line assembly.
Note that the reel assembly contains an assortment of slots (clips) for holding the line in place. The V-shaped clips are designed to hold line in place for extended periods of time (such as storing pre-loaded reels). The L-shaped clips are designed to temporarily hold the line in place for installation of the reel assembly.
(Re)wind the spool until approximately 6 inches of line remains exposed for each of the two lanes. Clip the exposed line into the L-shaped slots on each side of the reel.
Thread the lines through the metal eyelets on the spool (one line per eyelet). The lines should pass from the inside of the spool to the outside.
Install the reel assembly onto the shaft.
Once the reel is seated within the outer spool, gently tug on the two lines to free them from the temporary clips.
5. Reinstall the bump head knob assembly.
Install the bump head knob assembly onto the shaft.
Compress the spring while rotating the bump head knob until the internal threads engage.
Continue rotating the bump head knob until the assembly is hand-tight.
You don't have to leverage your savings to level your lawns. As you just learned, repairing your own equipment is easy when you follow our step-by-step guides. Not only did you restore trimmer functionality at a fraction of the cost of replacement; you have taken the edge off of future repairs, wherever you may find them.