DIY trimmer shaft
To identify faults in the electrical part, as a rule, just inspection is not enough, you need a multimeter or at least a tester with a dial.
Such malfunctions are characterized, as a rule, by the complete inoperability of the engine, severe overheating or jerky operation.
The check begins with the power cable, if it is damaged, it is either repaired or replaced.
Express check involves checking the voltage of 220 volts at the engine contacts.
The voltage should appear when the button is pressed, if the voltage is present, then we can safely say that the trimmer motor is faulty, it must be disconnected and carefully inspected.
Slight contamination of the collector plates and brushes is normal, but it is still better to clean with a soft cloth moistened with alcohol, if the brushes are clearly worn out, it is better to replace them.
Using a multimeter in the resistance test mode (the smallest limit. Ohms), touch the contacts of the brushes or the graphite brushes themselves with the probes, the tester should show a resistance of no more than 100 Ohm.
If the resistance is infinite (unit on the multimeter), then try to turn the motor shaft without removing the probes.
In a working electric motor, the resistance wakes up about 10.40 Ohm, if the brushes do not ring out, then there is no contact or the integrity of the stator windings is broken, possibly a break or burnout.
When the resistance is less than 5 ohms, there is an interspeed short circuit, most likely caused by a strong overheating of the engine.
To identify the specific cause of a motor malfunction, when the motor brushes do not ring, you can resort to the following procedure.
The graphite brushes must be pulled out by first pushing out the brass inserts or removing the pressure springs.
The collector motors in these devices are designed in such a way that the stator and rotor windings are connected in series, and in expensive models of electric motors a thermal relay is also connected to this serial circuit (110 degrees), such a relay in normal conditions keeps the power contact closed.
A separate diagnostic method is to check the resistance on the collector drum plates.
To identify the culprit of the malfunction, it is necessary to remove the insulation in the form of cambric from the fluoroplastic where the windings and the thermal relay are connected and ring each winding separately with a multimeter, as well as the thermal relay itself.
DIY trimmer shaft
An electric scythe or a trimmer, like any electric tool, has a limited service life. With an increase in the intensity of operation for various reasons, the life of the device decreases.
You should be prepared that at any time during operation, the electric scythe can break, but such situations can be avoided if you regularly disassemble, inspect and revise all important elements of the scythe.
Malfunctions of electric scythes can be very diverse, it can be either a breakdown in the electrical part of the engine and wiring, as well as in the mechanical part.
In most cases, it is not difficult to repair a trimmer or scythe and you can do it yourself if there is a minimum tool and basic concepts in technology. Well, for the readers of the site elektt.blogspot.com, I will reveal the main faults and secrets for a quick and reliable repair of your electric scythe, consider an example of repairing an electric scythe from Bosch and Gardener.
The design of most electric braids is not a complex device, the main components, be it a trimmer or braid, are an electric motor, a power wire, a button with a capacitor, a spool with a line that is fixed to the motor shaft or more complex mechanical options for braids where torque from the engine is transmitted to the spool through flexible shaft, but among electrical options for braids, this option is rare.
The most loaded mechanical elements of electric scythes are bearings and a trimer reel (spool).
In most cases, the device stops mowing due to the failure of its line spool.
The line has run out. According to the instructions provided, wind the fishing line on a spool.
The line is tangled. If the reel has not received damage, then you need to cut or unwind the line and, if necessary, rewind the entire spool.
The line is stuck together. Due to the rather intense work and high overheating, the plastic lines of the fishing line can fuse with each other. It is necessary to rewind the spool with new line and inspect the damage to the bobbin itself.
The motor runs but the line spool does not rotate. Most likely, there was damage to the structure of the reel with line. The spool bottom attachment points may break off, you need to completely disassemble the bobbin and, if necessary, modify the mount or completely replace it. In most electric trimmers, the bobbin is simply pressed with its plastic housing onto the motor shaft and, if overheated, when the plastic melts, it can turn and fly off altogether.
Both devices showed no signs of life, in the on state the engines did not work.
The case for both devices consists of two halves, self-tapping screws are on one side, which is convenient for disassembly.
After all the screws are unscrewed, the upper case is separated from the lower one by gently pressing it into the slot with a flat screwdriver to open the interlocked plastic locks.
After disassembly, we proceed to inspect the insides and troubleshoot.
During the inspection, it was found on the Bosch trimmer engine, on one of the brushes, which is fixed by the pressure spring, copper conductive wires flew off, which naturally was the reason for the absence of voltage on the brushes and the engine did not rotate.
The wire was restored to its place, and along the way the collector pads were cleaned, with a soft cloth soaked in alcohol, to a copper shine. The brushes were in good condition and did not need replacement.
It was also found that the switch does not create a reliable electrical contact, it was necessary to press the button with an effort, it was decided to disassemble the button, its contacts were cleaned of carbon deposits and lubricated with a current protective spray KONTAKT S-61.
With the GARDENER electric scythe, it was not so simple, it lay for quite a long time in a broken state, and literally “broken”, its rod at the place where the engine casing was attached was broken in half, apparently, the conditions of its operation were so difficult.
How To Change A Straight Or Curved Trimmer Shaft – Video
With the help of perforated plates from the metal profile mountings, a new mount of the engine body to the electric braid bar was not cleverly made. The integrity of the structure is restored, albeit not in aesthetic but in a reliable way, because in an electric braid, its main function is.
The engine shaft was turning noticeably hard; an internal inspection revealed burnt collector plates and worn brushes. The plates were cleaned with sandpaper to a shine, and the brushes were replaced with new ones.
In view of the long operation without lubrication and the subsequent storage of the device in an aggressive environment, the bearings are a little stuck and the motor shaft does not naturally rotate with difficulty.
The engine bearings were washed with WD-40 spray followed by lubrication. As a result, the engine began to rotate much better, but still the bearings were already “broken” and when the engine was running on the network, the sound of its operation was not so smooth and monotonous.
Further inspection of the electrical part led to the button, it was completely broken from its mountings, although it was pressed, the tester showed its malfunction. The button is not collapsible, so it was replaced with a new one. The fasteners had to be restored with hot melt glue.
In addition to the broken bar, there was a crack on the plastic protection, apparently someone did not drop it weakly. The scythe could work with it, but it was decided, as far as possible, to restore the protection structure.
Naturally, simply gluing such a loaded and impact-prone object with glue would not be a reliable solution. Therefore, using the same perforated plates from the metal profile, two brackets were made that created a “monolithic” connection of two parts of the cracked body.
The plates were connected to the body with aluminum rivets.
When the brushcutter was assembled, it was found that the bar at the points of attachment of the handle was poorly fixed and rotated, therefore the places where the plastic protrusions of the handle body were pressed against the metal of the bar were additionally sealed with a strip of cloth tape. Now the design has no extra backlash.
The main most common malfunctions of the electric trimmer and trimmers
Doesn’t cut the grass
The spool (spool) runs out of line. In most spools, the net feed is semi-automatic, with a light hit of the spring-loaded button on the ground, the line is fed to the exit. If the line does not feed, then you need to remove and disassemble the spool. spool and, if necessary, wind new line.
The line may be too long due to the fact that the blade, which is designed for cutting excess line along the length, is dull or it does not exist at all.
The length of the line should be slightly less than the diameter of the protection.
Vibration during operation
A large hum and vibration during engine operation may indicate that the bearings need lubrication or they have completely used up their resource.
Also, the body of the reel with the line (spool) may be cracked, and its attachment point must be inspected for cracks and damage.
Most of the electric motors in scythes and trimmers are collector and do not have a speed controller, with a decrease in the voltage in the network. speed and power decrease.
Line spool may not be properly wound.
Perhaps the turns are hampered by the presence of a stuck twig or a rope is wound around the shaft, you should inspect the structure. In a working spit, the shaft should turn easily and without the slightest effort even after it has been dispersed with a finger.
Electric scythe does not work
Does the engine not turn? We look at the presence of power on the plug, if everything is in order, then the device needs to be disassembled.
If no obvious damage is noticeable, then a sequential continuity of the electrical circuits of the device begins.
Using a multimeter (tester), first ring out the power cord, the fuse, if there is one, and the button.
If the button does not ring in the on state, then it should be replaced or if it is collapsible, then open and clean the burnt contacts.
The cord may be broken, in which case the engine may start intermittently.
An engine malfunction may be the fact that when the button is on, there is a voltage of 220 volts on the engine contacts, but it does not rotate.
Some electric motors are equipped with a thermal fuse that is built into the motor housing and tripped from overheating or simply failed. A working thermal fuse must restore its operation when the engine cools down.
How to fix a trimmer yourself
Trimmer repairs should be carried out as soon as possible at the first sign of breakage so that minor faults do not lead to more serious problems. All models are characterized by the presence of such basic units and structural elements: drive system (engine), transmission devices, working part (knife or fishing line), belts and handles. Failure can occur in any part, but some components fail much more often than others.
Motor-cutters that run on gasoline or electricity (as well as different models from different manufacturers) differ in design and the nature of the problems. Some of them can be easily eliminated with your own hands, while others will require more overhaul or contacting a service center.
Disassembly of the gasoline spit, lubrication of its parts and replacement of faulty elements
To disassemble a petrol cutter for repair work, you will need, in general, the following devices:
- a set of screwdrivers (with different tips) and wrenches;
- small puller for removing bearings;
- special candle wrench;
In each case, you will need to disassemble individual nodes.
It should be borne in mind that the starter (launcher) in a number of models is non-separable. in this case, in case of problems with it, only the replacement of the element is possible. If the knot is disassembled, then it can be repaired by removing and replacing the rope and spring, or reinstalling the latter (when it comes out of engagement).
Common malfunctions of electric trimmers
Electric trimmers differ from gasoline devices in a more simplified design. Conventionally, the electrical braid is divided into mechanical and electrical parts. Accordingly, the same groups of problems that occur with this equipment are distinguished.
Most breakdowns cannot be visually detected. To do this, you need to use various devices. You can visually determine the following:
- the integrity of the power cable is broken (insulation has been torn from it, or it is clearly broken);
- sinking or jamming of the start button;
- external mechanical damage to the brushcutter;
- problems with the cutting part;
- stopping the spit when clogging with grass;
- fork damage.
To find out which part has broken in other cases, you will need to disassemble the electric brace and consistently check the most likely options. At the same time, attention is paid to the external manifestations of deviations from the normal operation of the device. They help establish the cause.
Repairing an electric trimmer will require the following devices and tools:
- indicator screwdrivers;
- multimeter or tester;
- soldering iron;
- a set of keys;
- screwdrivers with different tips.
Electric braids often do not work due to reasons not directly related to them, but caused by a decrease in the supply voltage in the network or an inoperative state of the outlet used.
Parsing and replacing the rod
It is quite common to repair the trimmer bar. It is a structure of the following parts:
- a drive shaft made of steel with polyhedral or square splines at the upper and lower ends;
- aluminum tubes;
- a plastic sleeve designed to maintain the centralized position of the drive shaft in the tube (so that there are no vibrations);
- a rubber shock absorber needed to connect the rod to the motor;
- steering wheel with a handle used for steering and a rack, a belt.
On some models, a shock absorber is provided between the steering column and the boom. All control elements (lock lever, ignition switch, gas button) are located on the handle.
A bevel gearbox is attached to the lower end of the boom, but some lightweight models are available without it. This is due to the fact that their bar has a curved shape, and the shaft is a flexible cable.
How to disassemble the rod and then assemble it to lubricate the shaft or replace it is shown in detail in the video below. In the same way, replace a broken barbell with a new one.
It often happens that the multi-sided or square splines of the drive shaft “lick”, while the operating mechanism does not rotate or does it with a slip. Then the shaft is changed.
When a knock appears in the tube, you should disassemble the rod and check the condition of the bushing, and, if necessary, replace it. How to properly assemble the throttle handle on the trim is discussed in the video below.
If the rod is not intact, suitable for installation, then you can tighten the place of the break with a clamp or apply a kind of tire. This is a temporary measure and should be replaced as soon as possible.
The main malfunctions of gasoline trimmers
The most common are breakdowns of a petrol cutter associated with such structural elements:
- engine (in particular with a piston system);
- starter (rope breakage, breakage or spring disengagement);
- with an ignition or fuel supply system;
- transmission mechanism (reducer);
- filters and silencer.
The symptoms are as follows:
- the appearance of uncharacteristic sounds during the operation of the brushcutter;
- the petrol cutter does not turn on, does not pick up the required speed, or stalls;
- when the engine is running, the working part does not rotate or slips;
- gasoline leak;
- excessive heating of individual units.
Also, minor breakdowns may occur, which are detected without any special diagnostics:
- sinking of the start button;
- falloff of the limiter;
- line breakage or breakage (loss of sharpness) of the knife.
Minor faults are not difficult to fix. Repairing a gasoline trimmer in more complex cases will require preliminary diagnostics to find out the exact reasons. If you have the appropriate knowledge and skills of locksmith work, then the problems can be eliminated independently, replacing the failed parts.
Repairing a gasoline engine, carburetor and gearbox
Engine problems can be caused by problems with the piston system, oil seals, rings. To eliminate them, it is necessary to remove the drive motor.
Determining what exactly caused the breakdown is not easy. If there is a guarantee, the mechanism should be taken to a service center for diagnostics and repair. If it is not possible to turn to specialists for help, then it should be borne in mind that replacement of piston rings is most often required. To do this, you need to disassemble the engine, get the piston. This is done in the following sequence:
- remove the cover of the plastic case by unscrewing the screws or wringing out the clamps;
- disconnect the bar with the crankshaft;
- remove the cylinder head;
- take out the piston and rings;
- if necessary, replace them;
- assemble in reverse order.
Rings should be installed carefully because they are fragile.
How the piston is installed and the oil seals are replaced during engine repairs is clearly shown in the videos below:
With regular use of the brushcutter, the reducer may break. Gears and bearings wear out in it (they can also break). To prevent this from happening often, this unit should be regularly lubricated. The frequency is almost always indicated in the operating instructions for the model used (at least once a season). The video below can serve as a repair manual.
To lubricate the gearbox, unscrew the plug and simply squeeze out a suitable lubricant inside the unit by turning the shaft.
Troy-Bilt Trimmer Repair – Replacing the Lower Flexible Drive Shaft (Troy-Bilt Part # 753-05267)
The carburetor can only be removed and cleaned on your own, and the gasket between it and the engine can be replaced. The tightness of the assembly at home is quite problematic to determine. The main thing is to correctly assemble the equipment after repair so that the trimmer works without problems.
Disassembly and repair of electrical parts
Disassembly of the electric braid in order to repair its electrical part is carried out in the following sequence.
- Place the trimmer on a flat surface (such as a table) that does not contain unnecessary items.
- Unscrew the cover screws located on one side.
- Remove the unscrewed half of the case, gaining access to the start button, electric motor, brush assembly, bearings, electrical connections (these elements are shown in the photo below).
Disassembled electric trimmer
The brush and bearing units are shown in the photo below.
The braid will work without a thermal relay, only you will need to constantly independently check the temperature of the electric motor, periodically letting it cool down. You can also install a new similar sensor.
The start button of the electric motor can be checked by closing a jumper of its contacts. If the trimmer works, then the problem is clear. But this option is not safe. Everything should be done carefully so as not to get an electric shock. To change the button, you should use a screwdriver to remove it from the seat and connect the wires from the old to the new one. After replacement, you need to assemble the electric brace, and then check its performance.
Replacement of brushes is required if they have deteriorated. In this case, pull the old enough out of the grooves, and install the new ones in their place.
The connection terminals on different trimmer models are almost identical, so the connection and disconnection of the wires is the same.
Replacing the bearing is a rather difficult operation, because it can stick and not be removed from the motor shaft. Pull or knock it down carefully so as not to damage the rotor or seat.
Bearing for trimmer ET1003A
When the trimmer motor fails and needs to be replaced with a new one, carefully remove the fan and bearings and then reinstall them. In terms of costs, the replacement is almost comparable to the purchase of a new mechanism. In the absence of experience in working with electric motors, it is better to entrust its implementation to specialists.
How to lubricate a petrol trimmer with your own hands
In order for the lawn mower, it’s a petrol trimmer, to work properly, and the main units you had to change very rarely. use the lubricant correctly and regularly, and how to do it. “KosiKosa” will answer. It is important to select a special tool for the shaft, gearbox, rod and other elements. Sometimes even a new mower needs lubrication, if it was not foreseen in the factory assembly, therefore, it is optimal to purchase the tool with the tool right away.
How to lubricate the trimmer gear or petrol cutters
Before you lubricate the brushcutter gearbox for the first time, you need to carry out prophylaxis of the tool itself, and check for the presence of the lubricant put into the gearbox by the manufacturer. During operation, the lubricant is applied at the beginning and at the end of the season, and with intensive operation of the mechanism. every 30-50 hours of operation. Many readers and customers are interested in: how to lubricate the trimmer gearbox?
Our experts answer briefly and exhaustively:
- the product should be appropriately named “trimmer gear lubricant”. That is, trimmer lubricant is a completely different substance;
- the lubricant should be a transmission fluid grease, although today the manufacturer manages to fill the market with universal grease samples that fit all trimmer parts. Theoretically, it cannot be an ideal tool, due to the specific operating temperatures and friction force in each individual unit of the tool, but if you have not found a special one, you can try a universal one (carefully reading the instructions);
- if you need to lubricate the electric gearbox, as, for example, on the Makita ur3501 tool, then the choice of the grease of the same name will be optimal. This also applies to other trimmers, like Calm, Champion;
- for those trimmers whose brands do not produce special gear lubricant, you can use universal tools, after reading the instructions and comparing them with the parameters of your tool;
- we strongly discourage the use of Litol and lithium-based products, as they are not intended for the trimmer gear a priori.
It is possible to understand that a brushcutter, or rather, its gearbox needs lubrication, due to the fact that the tool overheats and the occurrence of noise inside the unit. In situations where noise is present, but the lubricant on the gearbox is also present, it must be completely replaced with a new one, but already from another manufacturer. The gearbox must be completely disassembled and lubricated no more than once a year. Several nuances of the actual lubrication procedure itself:
- Do not turn the trimmer, otherwise gasoline will leak out.
- We remove the electrical plug (cap) from the spark plug to avoid accidental start-up for safety reasons.
- We unscrew the side screw on the gearbox, without losing the sealing washer, counterclockwise. We use a key 17 or a hexagon.
- In the absence of grease on the outer end part of the screw, apply it in a volume of 3-4g.
- Scrolling the gear. we will help the lubricant to be distributed over the gears.
- The procedure is carried out several times.
- We tighten the screw back, not forgetting about the sealing washer.
NEVER BUY WEEDEATER STRING AGAIN!!! – WHO_TEE_WHO
Your tool also requires brushcutter oil during operation. It is also better to purchase it in advance so that the internal elements of the engine work properly and do not suffer premature wear.
Lubricate the petrol cutter, brushcutter: bar, drive shaft and other spare parts
The drive shaft, which is located inside the boom, transfers rotational movements from the engine to the trimmer gear, and that, in turn, to the knife or fishing line (depending on the type of cutting tackle of your unit). All of these elements, including the shaft, also require a lubricant to help prevent premature wear, breakage, friction, grinding, overheating, or breakage. It is imperative to lubricate the petrol cutter before storing it for the winter, as well as as necessary, when the details submit such a “request”. Several nuances in the implementation of the procedure:
Gearbox grease is listed as a separate product in the service catalog. Order it at a low cost, keep your gearbox running smoothly!
DIY ice screw from a trimmer
For fishing enthusiasts, ice fishing is a common thing. However, not everyone can have an ice screw at hand, and it takes a long time to break through thick ice with ice, inconvenient, and sometimes impossible. Is it possible to replace the auger ice screw with ordinary garden tools, which are present in almost all summer residents? This moment is especially sensitive for beginners who do not have a complete set of ice fishing equipment. However, why buy a separate tool if you can upgrade an existing one.?
Required materials and tools
It is quite easy to create an ice screw from a trimmer or brushcutter. It already has an element rotating from the internal combustion engine. It is he who is the main part of the gasoline unit.
For alteration, you will need a number of materials, tools.
- Reducer. This part is necessary to transfer the rotation of the engine to another shaft at a reduced speed, but with increased power. Gearboxes are rotating clockwise or counterclockwise, reversible, planar. For an ice screw, a reversing mechanism is suitable, which, when jammed, can rotate in the opposite direction. This will allow you to quickly remove it from the hole, because the ice on the rivers reaches a thickness of a meter or more.
- Steel tube for screw mechanism, tip, screw blade. The shape of the auger resembles a screw that easily bites into soil or ice. The auger can be created independently from a thick-walled hardened pipe and a welded-on screw made of durable steel.
- 2 bevel gears.
- 4 bearings.
- Output shaft.
- Gearbox housing.
A petrol cutter with an engine power of at least 3-4 hp is suitable for making an ice screw. Her efforts will be enough to make ice holes. powerful device is difficult to move in the field.
How to do it yourself
When preparing for work, it is necessary to select the location of the auger shaft in relation to the trimmer shaft. The circuit can be pine or tilted at a 90 degree angle. For self-assembly, it is better to choose a coaxial scheme.
Having prepared the necessary parts, let’s start assembling a new unit. The procedure is as follows:
- We attach the worm shaft to the motor shaft output.
- The coupling can be flexible or rigid. A rigid clutch is allowed with low engine vibration. If the motor shakes, a soft connection is the best choice for damping vibrations.
- The worm is connected to a double-row gear, the lower part of which is with a straight tooth.
- When assembling the gearbox housing, we leave a hole for filling oil.
- The rotation speed of the auger is regulated by the selection of gears of various sizes by the selection method or according to special tables.
Regardless of the assembly scheme, the angle of inclination of the axis, the ice auger must be equipped with an auger. When used on hard soils, the pipe must be hardened so that it does not deform during operation. Steel 65G is used for the screw. It is strong, but it bends easily, it is processed.
For the manufacture of the tip, a carbide metal is required, which is welded to the end of the pipe. Grooves are machined on its lower profile. They help to bite into the ground, ice.
The free end of the core is equipped with a shank. It, in turn, is connected to a clutch or drive gear.
The length of the screw is chosen depending on the depth of the ice, its density. In any case, it must be as strong and reliable as possible. The larger the hole diameter, the stricter the requirements for material strength.
For work with thin ice, the auger can be replaced with semi-disc cutting knives made of the same metal. For permanent work, it is better to place the gearbox and motor in a sturdy housing, which is equipped with non-slip handles. This will strengthen the structure and allow you to work comfortably.
Trimmer Gear Lubrication
Gears must be lubricated regularly in accordance with the recommendations set out in the operating instructions for the model used. This should also be done if:
- new gears were installed;
- atypical sounds emanate from the gearbox during trimmer operation;
- knives turn hard.
In addition to the gearbox, the trimmer shaft must also be lubricated regularly. This is the norm for proper care of the device.
With continuous use of the trimmer, the transmission is subject to stress from grass adhering to the blades, dirt or torque changes. The lubricant must be selected of high quality in order to extend the life of the gearbox.
Repair and lubrication of the trimmer gear
With frequent, intensive use of brushcutters, the gearbox may start to warm up or make sounds that are unusual for its normal operation, for example, grinding. This indicates that the mechanism needs to be lubricated. If this is not done in time, then more serious problems will arise (for example, gears will quickly wear out and need to be replaced), up to jamming. Other breakdowns also occur with the transmission. Repair and lubrication of the gearbox can be done independently. for this you just need to familiarize yourself with the features of these works and stock up on some of the available tools.
Used types of grease
When choosing a lubricant, the following factors must be considered:
- the degree of adhesion of the composition to the metal of the assembly;
- product brand;
- lubricant consumption by the transmission mechanism.
Well-known manufacturers, for example, Stihl, Husqvarna and others, in addition to trimmers, also produce lubricants for them. These products not only reduce wear, but also protect the gear metal from corrosion. Therefore, for brushcutters from these brands, it is better to use their own lubricating products.
If the compound used for lubrication has good adhesion, then it is practically not squeezed out of the gearbox through the gaps.
Different models consume grease differently. This is largely determined by the intensity of use of the brushcutter and the heating of the transmission mechanism. It is considered that the lubricant is sufficient if the temperature of the reducer during operation does not exceed 40 ° C.
By consistency, trimmer lubricants can be:
In terms of composition, the following types of lubricants are in demand:
- graphite, significantly reducing friction, as a result of which the rotation of the gears improves;
- lithium, which is also an excellent anti-corrosion composition, saturated with additives that increase the wear resistance of the metal without harmful substances;
- universal components containing highly refined mineral oils and improving performance characteristics.
Examples of suitable lubricants are: Champion EP-0, Gear Grease OREGON, Oleo-Mas, Azmol 158, Litol. 24. You should also pay attention to the advice of manufacturers on this issue and use the materials they offer. You can buy them at specialized retail outlets.
Champion EP-0 universal grease 120 gr
Main gearbox malfunctions and ways to eliminate them
Various breakdowns occur with the gearbox of an electric or gasoline trimmer. The most common of them are presented in the table below. There you can also find the causes of their occurrence and methods of elimination.
|Gearbox malfunction||Possible causes of breakdown||Remedy|
|the transfer unit is very hot||the use of an unsuitable (low-quality) lubricant or its absence||you need to replace or add lubricant|
|the gears are new and not worn down||for running-in, it is necessary to run for a short time without heavy loads with regular stops so that the mechanism has time to cool down|
|jamming of the shaft during rotation, the appearance of backlash and knocking||destruction or significant wear of any of the bearings||replace the failed bearing with a new one|
|the transmission mechanism flies off the brushcutter bar or staggers||damage to its hull||it is necessary to replace the part|
|in some cases, with minor damage with a clamp made of metal, the place is pulled together with a break|
|not fixed to the pipe||docking wear||you can make a winding from an electrical tape at the attachment point or change the bar|
|the output shaft with the knife does not rotate or stops in the event of an increase in the load||wear of teeth on gears or one of them||replacement of the interacting pair of worn parts is required|
Bearings are destroyed due to the use of inappropriate lubricant or due to lack of it. Also, their damage is caused by the harsh operating conditions of the brushcutter and the ingress of foreign particles of material (for example, broken metal teeth of mechanical transmissions) due to the fact that the integrity of the anthers is broken.
To remove the bearing, you need to disassemble the gearbox and use a special puller. If not, then you can try to do it with a hammer with a guide. In this case, work should be done carefully so as not to damage the seat. It is not recommended to use the preheating method to shoot the bearing. This is due to the fact that the metal can lose the required performance.
If the knife stops rotating under load or does not stop at all, then this is accompanied by an uncharacteristic sound.
Most gearbox problems can be easily fixed by hand. Replaceable parts are recommended to be purchased “native”, intended for the used brushcutter model.
Trimmer reducer device
A trimmer gear is a unit that transmits the rotational motion of the motor shaft to a knife or fishing line. It is located at the lower end of the brushcutter bar. The transfer unit is also designed to reduce the trimmer engine speed.
The mechanism consists, depending on the model of the brushcutter, of several gears rotating at high speed. As a result, they heat up due to strong friction. If there is not enough lubrication, or there is none at all, then the process leads to severe overheating and failure of parts, and, accordingly, the need to carry out complex repairs. To prevent this from happening, the transmission unit should be lubricated in time. The disassembled gearbox is shown in the photo below.
Gearboxes of modern trimmers of different models from different manufacturers differ from each other in design and seat size. It happens:
- in the form of an asterisk;
The most common round seat diameters are 24, 25.5 and 26 mm.
Brush cutters are equipped with gearboxes with different types of gears:
The drive shaft and gearbox are heavily loaded trimmer assemblies that are subject to significant wear. Between them, movement is transmitted due to the engagement of the teeth of the gears located at different angles to each other. The gear train works effectively only if there is no mechanical damage. In this case, the mechanism should not overheat, otherwise it may jam.
Algorithm for self-lubrication of the gearbox
For lubrication of the transmission mechanism, its preliminary disassembly is not necessary. A special hole for these purposes is already embedded in the device (it is shown in the photo below). In addition to gears, when carrying out lubrication, attention should be paid to the following elements of the mechanism:
- bearing unit;
- flywheel and starter coil pawl.
Lubricant injection hole
Fill in oil or add solid lubricant through a grease nipple closed with a screw. In this case, the actions are performed in the following sequence:
- clean the gearbox housing from dirt and adhered grass, especially carefully the area around the plug so that debris does not get inside the mechanism;
- using the appropriate tool (often it comes with a trimmer), unscrew the plug;
- into the open technological hole, the selected lubricant is injected from a tube, or using a syringe, as shown in the photo below;
- screw the plug into place.
When applying lubricant, you need to rotate the knife so that it is evenly distributed over the teeth of the moving gears.
If for any reason the gearbox needs to be disassembled, then the old lubricant must be completely removed from the entire surface of the gears and the housing, the shaft, and only then use a new one. The disassembled mechanism is convenient to lubricate with solid compounds.
The whole gear lubrication process is demonstrated in the video:
It is required to lubricate the transmission unit at least once a year, but it is recommended to do this every 20 hours of intensive use of the brushcutter. If the first signs of malfunctions appear with the mechanism, then you need to add the lubricant as soon as possible.
How to replace the trimmer gear: the algorithm of actions
To replace the gearbox with a similar part from the same manufacturer, it must first be disassembled and removed from the rod. In this case, they act according to the following algorithm:
- loosen the tie bolts located under the transmission;
- using round nose pliers, remove the two corkscrew rings;
- using a puller, pull the bearings from the driven and drive shafts;
- then the mechanism is assembled, in the reverse order, installing all the parts.
Disassembled transmission mechanism is shown in the photo below.
If the puller is not at hand, then you can try to gently knock down the bearings. When they are stuck and do not budge at all, you can heat them with an industrial hair dryer (at a temperature of 600 ° C) and remove.
Assembling the transfer assembly is easier than disassembling it. You may only need to tap lightly with a hammer to set the parts in place. After assembly, it is imperative to check that the driven shaft can be rotated by hand.
When there is a need to replace the transfer unit with a non-original part, then their interchangeability should be taken into account. It should be borne in mind:
- rod diameter (this parameter is often 25.4 or 26 mm);
- the parameters of the drive shaft. the shape of the docking place and the diameter (its common value is 8 mm);
- protection fixing option.
If the considered parameters match, then it will be possible to install a part from other models.
Timely lubrication of the gearbox will ensure its long-term operation without repairs. In addition, modern materials protect the metal well from corrosion and increase its wear resistance. When choosing, preference should be given to the lubricant recommended by the manufacturer of the trimmer being operated. If it is not possible to acquire such compositions, then the considered or other analogs suitable in terms of properties should be used. When it is necessary to disassemble the mechanism during repairs, this should be done carefully so as not to damage individual parts.