How to fill a line for a trimmer on a brushcutter. petrol grass trimmer

line, trimmer, brushcutter, grass

How to change a line for a trimmer in a trimmer

The grass trimmer is the most common tool used for cutting grass and small shrubs. This unit is characterized by its ease of maintenance, uncomplicated operation during work, and thanks to its low weight even women cope with it. It’s no secret that high-quality grass mowing requires the right choice of cutting tools. As the latter, trimmers use special cutting nozzles (disks, knives) or trimmer heads with a fishing line inside. Trimmer nozzles and line are consumable tools, but while blades can be sharpened, when the line is used up, it needs to be replaced. In this article, we will tell you in as much detail as possible how to correctly replace the fishing line for the trimmer.

Refilling the Spool. (PGMT/PGBC-5200)

Grass cutter head is a cylindrical body, in which a spool is inserted with a thread (filament). This design can be installed on both gasoline and electric trimmers. Heads differ in the way they are threaded and fed and come in 3 types.

  • Automatic. The filament is fed after the user reduces the engine speed. Although automatic line feed is convenient if you do a large amount of work, but these bobbins have one drawback. a high consumption of thread.
  • Semi-automatic. This type of head does not require the user to perform complex manipulations. These extend the filament automatically while the machine is running at full speed. It is enough to slightly knock the grass trimmer head on the ground (this removes the cord lock), and the line for the trimmer due to the centrifugal force is pulled out of the bobbin, after which it is cut to the right length by the knife located on the protective cover.
  • Manual. Cord extension requires the machine to stop and the line for trimmer is pulled out manually.

Based on the above, semi-automatic bobbins are the best option. Also keep in mind that the grass trimmer coils for grass are single string (used only for grass trimming) and double string, which are used for mowing tall grass and small, with thin stems of bushes.

We will need

By the way, there is more than one way to tuck the line for the trimmer into the reel, but I assure you that this is the easiest and most reliable.Let’s begin. For convenience, remove the mowing head from the grass mower. Clean it with a rag from the adhered remains of grass.Unwind the necessary amount of fishing line from the reel. This distance depends on many factors: the manufacturer of the grass trimmer (namely, the volume of the spool), the thickness of the purchased line. First, take a 2-3 meter long section. And bite it off with a pair of wire cutters.

Then bend it in half so that one end is larger than the other by about 15 centimeters.Put the middle on the spike between the grooves.

We will wind it simultaneously in both directions. Wind the line for the trimmer and fix it temporarily in the grooves.

The winding direction is indicated on the bobbin by an arrow.Then thread the whiskers through the holes in the top cover. Put it on the base and snap.

Put the reel on the grass trimmer and start mowing.If the edges of the fishing line are too long, they can be bitten off with wire cutters to the desired length.

Winding a double line

Usually a spool is divided into 2 parts by an ongoing partition. It is necessary to take the line for trimmer from the coil and wind it in one half to measure the capacity at the chosen cord diameter. Wind it so much that the cord does not protrude. As soon as half of it is full, you need to coil back the line for the trimmer, remembering the used meterage. The cord should be cut to a length exactly 2 times longer than was placed on the half of the spool.

Having reached the end, it is necessary to fix the ends of the line in special opposite notches on the side of the spool. As one of them is longer, the free tails at the output are almost the same.

Now you need to insert the spool into the base with a spring. In doing so, the ends of the fishing line are threaded through the holes in the mowing head. They are pulled up to free themselves from the grip of the slots on the reel. Then the cap is put on, and the head is ready for use.

Characteristic faults and troubleshooting

Naturally, the owners of trimmers face certain mowing head failures during the operation. These faults are most often caused by some difficulty in extracting (lengthening) the cutting filament from the reel. The most common causes of no line feed are that the line is “bitten” between the coils or is sticking together.

If the line is not fed

In this case the reason of defect is incorrect winding of cutting filament. the line for the trimmer may be wound with insufficient tension, which contributes to the crossing of the coils with each other and tangling of the string. When the spool rotates, the cutting filament is drawn in by the centrifugal force produced, which in its turn causes the free end of the line to be caught between the coils. To correct this fault, you must dismantle the spool, disassemble it and rewind the string so that the coils lie in even rows, tightly pressed against each other.

If the string is sticking

The coils of the fishing line may stick together directly in the mowing head:

Tip! To prevent the filament from sticking inside the mowing head, experts recommend applying a thin film of silicone grease on the surface of the filament after threading the line into the spool. In addition, it is better not to use fishing line for trimmers from unknown manufacturers.

If the user still can not avoid the sticking of the fishing line, then to repair the grass trimmer reel to remove and replace the existing cord with a better quality.

If the string flow is too high

When using semi-automatic mowing heads, you may experience an increased flow of line because the lines are lengthening by themselves. As a rule, this occurs due to the loosening of the spring installed inside the reel. The malfunction can be eliminated by placing washers under the spring.

If the bobbin does not spin

Failure of the semi-automatic grass trimmer reel can also be caused by frequent collision of its head with hard objects (dry branches, soil, stones, etc.).). In this situation the line is slightly stretched and then rapidly retracted inside the reel. The line is heated up due to the friction, which can cause the line coils to stick together. To remedy the defect, the line must be rewound.

If the line feeds in spontaneously

Unintentional lengthening of the line with subsequent cutting of the line ends may be due to incorrect assembly of the cutting head after a cord replacement. Inexperienced users often forget to install the compression spring inside the head, which causes premature activation of the line feed mechanism.

line, trimmer, brushcutter, grass

Dismantling the mowing head

Proceeding to the repair head trimmer for grass, the owner must protect yourself from injury if the engine is accidentally started, which is imperative to completely disconnect the electric garden tool or shut down the engine brushcutter. often than not, the owner of the grass trimmer faces the need to replace the cutting cord. after removing the head from the shaft. do it carefully, to avoid damaging it.

Important! Gear shaft, which the grass trimmer is equipped with, has a left-hand thread on the end, so the mowing head is unscrewed clockwise when removing.

Dismantle the coil in the following order:

  • align the holes on the shaft and the washer, fix the mower shaft firmly with a screwdriver or a metal bar;
  • Unscrew the actuator by turning its body clockwise.

Having removed the mowing head, proceed to its disassembly, for which you need to carefully open the cover, which is most often attached by specially provided plastic locks. To do this, press the edge of the cover and at the same time push the latch into the housing.

Warning! If the grass trimmer is equipped with a semi-automatic head with a button at the bottom, then open it with extreme caution. when you remove the cover may fly out and lose the clamping spring.

Charging the line into the bobbin

To charge the line for the trimmer correctly, it is necessary to act according to the instruction manual attached to the trimmer. As a rule, this operation is carried out as follows:

At this point, charging the mowing head with cord can be considered complete. The coil is screwed on the shaft of the trimmer for grass, preliminarily fixing it rigid. How to do this is described above. Check the mowing head’s functionality by mowing a small patch of lawn.

Tip! In cases where the owner of the grass trimmer prefers to replace the failed head with a new one, experts recommend avoiding the purchase of cheap non-original coils, brought from China.


Identify line types by their cross section. Most often buy goods with a circular cross-section. They are inexpensive and do a great job of mowing brushwood. But its disadvantage is a loud noise, similar in strength to the whirring of car engines. Manufacturers can demonstrate spiral-shaped cords that have much less sound.

Threads of square, rectangular and star-shaped cross-sections are also popular. Goods with jagged, sharp edges are in special demand, because the lawn is cut perfectly with such edges.

There are versions with notches and grooves, which can be used to mow impassable weeds. The volume level is low, so extra power is added.

Handle shape

Manufacturers offer 2 handle options:

Handle in the form of the letter “T” is installed on models with auto-winding line. Work is done with 2 hands on either side of the boom. Such position is convenient for mowing large areas of vegetation. The cutting is performed on the principle of a grass scythe. from one side to the other. Such a variant is not distinguished by maneuverability, it does not work well on a difficult terrain. Bicycle handlebar can be equipped with control buttons. In domestic types of grass trimmer start buttons are installed on the boom.

Classic grass trimmer with a reversible handle with control buttons

Gasoline trimmer with D-handle is more maneuverable, it is convenient for cutting grass in areas with difficult terrain. In such a tool, the hands are positioned one above the other. The disadvantage of the handle. it is difficult to hold it, the management of such a device is more complicated.

The handle in the form of the English letter “J” is the most uncomfortable, so it is rarely found.

Choice of line

In order to easily wind the fishing line for the trimmer on the grass trimmer reel, it is worth to determine what tasks the garden tool will perform. The thicker the thread tucked into the head, the more difficult the tasks it will be able to perform. It should be noted that often a universal thread is used, the width of which does not exceed 2 mm. You, in turn, can determine the size, using the following methods:

  • Read the information in the manufacturer’s instructions;
  • Check the suitability of the line yourself by trying to insert it into the hole in the reel;
  • Examine the bobbin for information on the diameters allowed for use.

Selecting a fishing line for threading into the grass trimmer reel can be done by the type of motor. For example, excessively thick fishing line may cause an increase in rotational resistance. This will increase the load on the engine, which will certainly affect the quality and life of the engine.

Avoiding negative consequences is easy. To do this, you need to take into account that for electric motors with power up to 500 watts is ideal for trimmer line with a diameter of up to 1.2 mm. If you can’t get it, you can use 1.6mm cord. Filament with a diameter of 2 mm is used for motors with a power of more than 1 kW. It is worth noting that a 2 mm cord is often used for winding on a bent mower. If a gasoline-powered device has a straight shaft, you should use 2.5 or 3 mm yarn. The thickest lines are installed only on devices with power equal to or greater than 1.3 kW.

Last, but not least, is the type of line section. When choosing it, it is worth focusing on the tasks set before the gardening tool. There are several in-demand cross-sectional options:

  • Twisted. has a small safety margin, which makes it suitable only for young grass;
  • serrated. characterized by sharp edges, suitable for working on overgrown weeds;
  • round. the most common cross-section. Such lines cope well with fresh grass, but are not suitable for shrubs and dead wood;
  • Rectangular, square and star-shaped cross-section types. due to their low strength are used for working on lawns.

The strongest and most versatile cord is the two-piece trimmer line with a round section and a core inside. This is the kind of thread that is suitable for most jobs. At the same time, it should be remembered that the use of fishing line, ordinary wire and other third-party materials as a cord carries a danger to others.

line, trimmer, brushcutter, grass

All about changing filament on a trimmer head

There are many types of heads, which are designed for different types of line. The latter is also available in several diameters: from 1.0 mm to 3.2 mm. And it is available in round (including a special groove for noise reduction), square, twisted and star-shaped.

There is no clear preference, and this explains the large variety of shapes and diameters on the market. The round shape is usually stronger, but has a worse cutting ability, in addition, when rotating it makes a characteristic sound. That’s why sometimes they make an acoustic groove on it, but the use of this line makes sense only on cordless trimmers, machines with gasoline-powered and mains drive have the sound level of the drive itself almost drowns out the sound of the line. A square has a good cutting ability, and even though this trimmer line is less strong than a round line, on average it uses less. A square line for a trimmer quite easily cuts the same willow growth up to 1 cm in diameter. The star has the maximum number of cutting edges, it mows the best and consumes the most quickly.

Soaking Your Trimmer Line to Make it Last Longer

The next nuance in the choice is the stiffness. The fact is that in the manufacture of nylon, a modifier (often maleic anhydride) is added to it, which improves its strength and prevents tearing. However, modifiers are not the cheapest component, they try to save on it. Therefore, a seemingly good line for the trimmer, which was left for the winter, suddenly behaves completely different in the spring. torn, ceases to normally come out of the spool. There is a recommendation to soak trimmer line in water before work, but I do not see much sense in this, maleic anhydride interacts with water, but if it is not enough in nylon. then there will be nothing to interact with. Therefore, it makes no sense to stockpile fishing line for a long period of time, broken or constantly tearing line for trimmer, which also does not want to go out of the spool itself, can significantly complicate the work.

Winding a fishing line

The next step is to wind up the trimmer line, making sure that each end is in its groove. When it is wound, the ends of the fishing line should be temporarily inserted into the side grooves.

Then we insert the spool into the head, put the cover on top, straighten the ends of the fishing line so they come out of the grooves, and then fix everything on the latches.

For details on how to wind fishing line on the head of the trimmer for grass, you can see in the author’s video. This review is based on a video from the YouTube channel HotSEM.