Stihl trimmer line replacement

Replacing Trimmer Line

When using your trimmer equipped with a nylon line cutting head, one thing is surely a given: eventually you will need to replenish the cutting head with line.

In this brief video, we'll explain how to replace the line on our three most popular spooled line heads: STIHL AutoCut, STIHL AutoCut EasySpool, and the STIHL TrimCut.

Removing the Head

To remove the spool from the head, follow these steps:

Always stop the engine and make sure that the cutting attachment has stopped. If the trimmer utilizes a gearbox, make sure it has cooled down before doing any maintenance or repair work to the cutting head or attachment.

Shown here is the STIHL AutoCut 25-2 trimmer head.

Grasp the body of the spool housing firmly with one hand. With the other hand centered over the tapping side of the head, insert your thumb into the hole where the tab release is located and push down firmly toward the base of the spool housing. This will release the tab.

Rotate the head around 180° and repeat the same procedure on the second tab. The cover is now released and you can remove it and the spool. You may need to press down on the spool and rotate it slightly for it to release from the spool housing.

On the TrimCut, you simply unscrew the star nut on the head. Once the star nut is loose, remove the nut and the spool.

Although you do not have to open up the head on the EasySpool to wind it, if you wanted to clean the inside of the head, you simply loosen the cap and lift the spool out of the spool housing. Be cautious not to lose the spring that is located in the center of the spool.

Winding the Spool

Once the cap and spool have been removed on the AutoCut or the TrimCut, this would be a good time to wipe away or tap out any loose dirt or debris that may have collected in the head.

One way to reload your trimmer head is to use a pre-loaded spare spool that can be purchased at your STIHL dealer, but eventually you will need to rewind your spool or spools.

To do this, first determine the correct diameter of line you will need and the length of line required to wind your head. This information can be found on the instruction card that comes with your STIHL trimmer head. If you cannot find those instructions, they can easily be viewed or downloaded free of charge at stihlusa.com.

In our example here with the AutoCut 25-2, the instructions call for two pieces of .095 line that are 16½ feet long.

To get your two lengths of line easily, measure off one length of line 33 feet long. Fold the line in half and make your cut at the halfway mark. This will give you two correct lengths of line.

You're now ready to wind your spool.

There are a few important features on your spool that you will need to identify first. On the top of the spool, you will find two or more notches. These are there to hold the line in place once the spool has been wrapped.

Second, you will see the spool is split and has line-retaining holes. There is an identical set of retaining holes located 180° around the other side of the spool.

Finally, on the bottom, you will see the correct winding direction for the line.

Winding the Second Line

Taking one line, you will want to wind the half of the spool that is closest to the notches first.

Make a mental note of the position of the retaining hole you start with. When you wind the second line, you will want to start on the opposite side of the spool.

Insert the line as far into the retaining hole as you can, then wind the line around the spool firmly and evenly, not crossing over into the other half.

When you have approximately 5 inches of unwound line, insert the line into a notch in the spool.

Insert the second length of line into the opposite side of the spool, in the unwound half and in the retaining hole that is 180° opposite the first line you wound.

Repeat the winding process, leaving about 5 inches of unwound line, and insert this line into the notch opposite the notch where the previous wound line is secured.

Carefully place the spool into the spool housing with the notches located just to the side of the eyelets. Press down on the spool and rotate it slightly until the notches and the eyelets match up, then release the spool. It should remain in this position.

Gently pull the line out of the notches and feed it through the eyelets.

Place the cover on the head, making sure that the tabs line up with the tab-release holes, and press down until you hear it snap into place on both sides.

Pull on the line to make sure all the slack has been taken up and the spool engages.

On the TrimCut, you will need to feed the line through the eyelets in the spool housing, then carefully lower the spool into the housing.

Pull firmly on both ends of the line to release the lines from the notches, then reinstall the star nut.

Again, pull on the line to make sure all the slack has been taken up and the spool has engaged. The line should be the same length on both ends and never longer than the line-limiter distance located on the trimmer guard.

If one line is longer than the other, or if the line is longer than the line-limiter distance, trim the line back as necessary.

AutoCut EasySpool

The AutoCut EasySpool loads in a much different way.

First, make sure that the arrows on the spool housing and the spool are aligned. Then firmly insert the end of the line into the outlet hole as far as you can, approximately 2 inches.

Repeat the same procedure on the opposite side of the head.

Note the winding-direction arrows on the top of the spool. Turn the spool in this direction and you will automatically wind the line onto the spool.

Make sure all the parts are snug on your trimmer head, and you're ready to go back to work.