Restring Ryobi 40-Volt String Trimmer | Guide & Tips

If your Ryobi 40V string trimmer is struggling to cut cleanly or the spool has run dry, restringing it is a quick fix you can handle in minutes. The process relies on the bump-head’s internal through-loading system, which eliminates the need to remove the spool on most models. Here is exactly how to do it, step by step.

Restringing the Ryobi 40V: Battery Removal and Arrow Alignment

Before you touch the trimmer head, press the battery release latch and slide the 40V pack off the shaft. This is a mandatory safety step that prevents the trimmer from starting while your hands are near the cutting line. Place the trimmer on its side and locate the alignment arrows molded into the bump head. These are usually on the upper and lower halves. Rotate the lower cap or dial until the arrows point directly at each other. You should feel or hear a click when the internal line channel aligns and opens.

Choosing and Feeding the Trimmer Line

Most Ryobi 40V string trimmer heads accept 0.065-inch or 0.080-inch diameter trimmer line. The exact size is often printed on the head itself. Using the wrong diameter leads to jamming or poor cutting performance. Cut a single length of line between 10 and 16 feet, depending on your head’s capacity. Insert one end of the string trimmer line into the hole on the side of the head that is now aligned. Push it straight through until it emerges from the hole on the opposite side. Pull both ends of the line outward so they are perfectly even. An uneven load will cause the trimmer to vibrate excessively during use.

Winding the Spool and Testing the Trimmer

Hold the outer casing of the trimmer head steady with one hand. With the other hand, turn the inner dial or cap in a clockwise direction. This winds the line onto the internal spool. Maintain gentle, even tension on the line to prevent it from crossing over itself. Continue turning until approximately 5 to 6 inches of string remains protruding from the head. This tail is essential for the bump-feed mechanism to function correctly. Reinstall the 40V battery pack. Start the trimmer and test the line advance by lightly tapping the spinning head on the ground. The line should feed out and the built-in blade will trim the ends to the correct length. If you are looking for a reliable replacement or a second unit for heavy-duty work, our team has tested the top options available today in our guide to the best 40-volt string trimmers on the market.

FAQs

Do I need to remove the spool to restring my Ryobi 40V trimmer?

No. One of the key features of the Ryobi 40V bump head is the tool-less, through-the-head loading system. Aligning the arrows on the head opens a direct channel for the new line to be fed straight onto the internal spool without any disassembly.

How much string does a Ryobi 40V trimmer head hold?

Capacity varies by head model. Standard bump heads typically hold between 10 and 12 feet of 0.065-inch line. Larger Expand-It heads can hold up to 16 feet of 0.080-inch line. Always check the label on your trimmer head for its specific capacity.

Why won’t my Ryobi 40V trimmer feed more string?

The most common cause is using the wrong line diameter, which jams inside the eyelet. Other causes include winding the line too tightly or a broken internal spring. Try using a thinner line and ensure you are tapping the head firmly on the ground while the trimmer is running at full speed.