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, 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 mower 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 point wear | you can make an insulating tape rewind 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 harsh operating conditions of lawn mowers 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 purchase “native”, intended for the model of lawn mowers.
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.
Grease 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.
Gear lubrication
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 can be conveniently lubricated with solid compounds.
The whole gear lubrication process is demonstrated in the video:
Lubrication of the transfer unit is required at least once a year, but it is recommended to do this every 20 hours of intensive use of the lawn mower. If the first signs of malfunctions with the mechanism appear, then the lubricant must be added as soon as possible.
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 subjected to stress from grass adhering to the blades, dirt, or due to changes in torque. 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 lawn mowers, the gearbox may start to warm up or make sounds unusual for its normal operation, such as grinding sounds. 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, you must consider the following factors:
- 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 lawn mowers from these brands, it is better to use their own lubricant 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 have different grease consumption. This is largely due to the intensity of use of the lawn mowers and the heating of the transmission. 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:
- liquid;
- semi-liquid;
- solid;
- plastic.
How to service a gearbox on a hedge trimmer #Smallenginenation
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
Trimmer reducer device
A trimmer gear is a unit that transmits the rotational motion of the motor shaft to a knife or line. It is located at the lower end of the lawn mower bar. The transfer unit is also designed to reduce the trimmer engine speed.
The mechanism consists, depending on the model of the lawn mower, of several gears rotating at high speed. As a result, they heat up due to strong friction. If there is not enough lubricant, 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:
- round;
- in the form of an asterisk;
- square.
The most common round seat diameters are 24, 25.5 and 26 mm.
lawn mowers are equipped with gearboxes with different types of gears:
- conical;
- worm;
- spiroid;
- cylindrical;
- planetary;
- wave;
- combined.
The drive shaft and gearbox are heavily loaded trimmer assemblies that are subject to significant wear. Between them, the 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.
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 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);
- 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.
What kind of lubricant should be used for the trimmer gear?
In the process of operation, the mechanical part of the trimmer is loaded by contact forces on the teeth, resistance reactions from adhering grass (sometimes with dirt), dynamic, shock loads due to constantly changing torque. Lubricant for the trimmer gear must fully take into account these features, so the selection of the brand must be strictly individual.
The following factors are taken into account:
- Manufacturer’s brand. Each brand reasonably focuses on self-made lubricants (you can talk about cheap Chinese products later). This applies to manufacturers such as Husqvarna, Stihl, Huter, Makita, and others. The only exceptions are domestic-made trimmers: for example, the Caliber in the user manual does not indicate the brand of lubricant at all.
- The viscosity of the lubricant. As you know, all lubricants are divided into three groups. high-viscosity (colloidal systems containing various additives), plastic compounds for universal use and solid lubricants that soften during operation.
- Good adhesion to the surface of gearbox parts, as a result of which the grease is not squeezed out into the gaps or out of the unit.
- Intensity of grease consumption by the gearbox. Here you have to rely on your own experience and the recommendations of specialists, since some trimmer manufacturers, relying on the availability of their own service centers, do not give clear recommendations at all regarding the period of operation of the gearbox between two lubrications.
Lubricant consumption also depends on the temperature at which it retains its lubricity. When the gearbox is heated to 40 ° C, it is considered that its operating conditions are satisfactory, and there is sufficient lubrication.
It is believed that there is no universal lubricant for the trimmer gearbox, but this is not entirely true. In fact, a suitable lubricant will be one that contains the following components:
- Lead-free antiwear additives;
- Solid lubricants with the presence of graphite or molybdenum disulfide (the latter is preferable, since the lubricity is fully retained for a wide range of shaft revolutions);
- Only mineral (inorganic!) Oils, highly refined.
These requirements are fully met by Gear Grease OREGON or Champion EP-0 lithium greases, domestic compositions Oleo-Mas, Litol 24, or Azmol 158, as well as those recommended by the manufacturer of a particular trimmer model.
Lubricant for trimmer gear. How and how to lubricate?
Sometimes, in the midst of an intense mowing operation, your trimmer will start making an unpleasant, grinding noise. This complains about the lack of lubrication, the gearbox is the most heavily loaded unit of the device. And soon these “warnings” may be followed by a jamming of the drive.
How to lubricate the trimmer gear?
In the upper part of the body, where the gear block is installed, there is a technological hole, which is plugged with a screw during trimmer operation. This screw is unscrewed, and 1.5. 2 ml of grease is injected into the hole using the spout on the tube. If the lubricant was purchased in a different package, then an ordinary disposable medical syringe is also suitable for this operation.
After that, the screw is reinstalled. This procedure, regardless of the user’s recommendations, should be performed every 10. 15 hours of operation of the trimmer in working mode. Other reasons for updating or replacing the gearbox lubricant are the independent performance of minor routine maintenance (for example, cleaning and flushing the gears of the gearbox before the start of the summer season), repairing the unit, preserving the trimmer for the winter, etc.
If the gear unit is disassembled, it is recommended to completely remove the remnants of the old grease from the surface of the parts, even if it does not have any traces of oxidation and contamination. And only then apply new grease. After applying the lubricant, it is recommended to rotate the shaft several times by hand, and make sure that the lubricant is evenly distributed over all parts of the gearbox.
When lubricating, pay particular attention to the following elements:
- Flywheel: on its surface, as a rule, grass residues adhere intensively, and thickening herbal juice creates additional resistance.
- Pawl of the starter coil, which in the process of turning on the drive constantly comes into contact with the grooves on the flywheel. In this case, not only mechanical wear occurs, but also mechanochemical corrosion of the flywheel-dog connection, since the materials of this pair are different (the flywheel is aluminum, and the dog is steel).
- Bearings, if their seals are worn out, and through them, the remaining grease is squeezed out. In this case, the unit begins to vibrate intensively when loaded. This happens with Chinese-made trimmers, so it is worth thinking in the future about replacing the bearing assembly with a better one, for example, from the Swedish company SKF.
Trimmer Gear Lubricant
Trimmer gear lubricant: which one to choose?
Choice of reducer paste
Currently, the market for gas powered tools and consumables offers a wide range of greases that are designed to reduce friction and overheating of rubbing parts. Therefore, each owner, when the time comes for maintenance, is faced with the problem of how to lubricate the trimmer gear for its long-term operation. For these purposes, special plastic pastes are used, which differ in properties and manufacturer.
How to lubricate the trimmer gear
Disassembled lawn mowers gearbox
Almost every lawn mower gearbox is equipped with a small technological hole, which is plugged with a special bolt during operation. After thoroughly cleaning the unit from grass residues and debris, it is necessary to unscrew the screw and inject 1.5 to 3 ml of grease into the cavity of the gearbox, depending on the brand of the tool. For ease of dosing, you can use a traditional medical syringe. During the operation, foreign particles and objects must not be allowed to enter the gearbox, as this can lead to intense wear of the gear train, as well as its jamming.
Experts recommend that at the end of the mowing season and long-term storage of the tool without work, disassemble the gearbox, wash gears and bearings, and re-lubricate the unit.
How to lubricate the gearbox of lawn mowers, petrol trimmer
Side bolt 17 on the gasoline trimmer gearbox
For safety reasons, in order to avoid accidental starting, all maintenance work on the lawn mower must be carried out with the electrical cap / plug removed from the candle. Do not overturn the trim tab to avoid gasoline leakage.
Unscrew the side screw on the lawn mowers gearbox. Depending on the manufacturer of the garden tool, instead of the hexagon screw, there can be a turnkey bolt, usually 17. The thread is ordinary, unscrew it counterclockwise. Do not lose the sealing washer.
Add specialized lubricant
If grease is not visible on the inner end of the screw, then add 3 to 4 grams. Rotate the gear by hand, changing the direction of rotation so that the grease is distributed over the gears.
Then reinstall the screw by tightening it securely.
Time and procedure for preventive maintenance of the gearbox
I recommend in order to carry out preventive maintenance of a new gasoline trimmer immediately after purchase, with the addition of lubricant to the gearbox. With all the high cost of garden equipment, some manufacturers save money and put in lubricant only at a minimum, for the run-in time.
Checking the correct lubrication of the gearbox angle grinder
The last step in servicing your angle grinder is to check that the lubricant is correctly applied and distributed inside the gearbox. To do this, after the gear unit is assembled, the power tool is turned on without load for a few minutes, while ensuring that there are no extraneous sounds, odors and other things. If they occur, you must immediately disconnect the angle grinder from the mains. The heating of the gear unit is also checked. The lubricant must distribute heat evenly and the temperature of the gear unit must not be too high.
After a short work, unscrew 4 screws, then remove the cover from the gearbox. Visually inspect the helical gears for lubrication. If it is absent, then too little lubricant has been loaded and should be reported. If in the process of work it squeezes out of the cracks, then it was laid too much and the excess should be removed. After making any changes, check the operation of the angle grinder again without load.
How to lubricate the lawn mowers’ gearbox
Buying any technique of its kind is a lottery, but a lot also depends on the gardener. In caring hands, Chinese samples serve for a long time and do not let their owners down at the wrong time. And if you forget to lubricate the gearbox of lawn mowers in time, do not clean the filters, use cheap low-quality gasoline, then garden equipment from the most famous brands will become a headache.
Lubrication of the lawn mowers’ gearbox is one of the most important maintenance elements of the gasoline trimmer, which must be carried out directly by the user.
How and how to lubricate the gearbox of lawn mowers?
Responsible maintenance is the key to long tool life. One of the requirements in the operation of a lawn mower is the timely lubrication of the gearbox, as well as cleaning the filters. With what composition to lubricate the gearbox, every user of such a unit knows. First, it is cleaned in several stages, then the element is removed from the casing. It is cleaned with gasoline and dried. The place for the filter is prepared carefully, cleaning it from dust and old oil. The main signal for lubricating the lawn mowers gearbox is extraneous noise and rapid heating of the equipment. This means that it is necessary to lubricate the spare part as soon as possible. For lubrication intervals, refer to the instruction manual for your lawn mower. Experts say gearbox maintenance should be done every 15 hours.
Petrol trimmer grease
Correctly selected lawn mower care guarantees the durability and quality of the equipment. Manufacturers try to take into account all the nuances and prescribe what materials to use for maintenance. Usually, a specific type of lubricant is not indicated, it is simply given generally known standards that lubricants must comply with.
The lubricant must be selected in such a way as to take into account temperature conditions, rotational speed, load dynamics and vibration. The main requirement is that this mixture remains in the zone of maximum friction.
Lubricants must have good anti-corrosion properties, reliably protecting components from rust.
Based on the above information, it should be noted that lawn mowers manufacturers are developing universal additional tools for their equipment. It can be served with general industrial compositions. The main condition is compliance with the operating conditions, namely, the presence of an anti-rust and lime agent in the composition, as well as a filler, which consists of a solid lubricant. Grease is poured into the gearbox through a special hole, the unit is not dismantled.
Replacement is done quickly enough.
- First, turn off the device from the network. Devices using gasoline must be drained of gasoline.
- If the lubricant changes completely, then be sure to flush the gearbox. To do this, first fill in the cleaner, then rinse the gearbox well, then drain. It is important to clean the case completely.
- With the special tool that is included with the trimmer, you need to unscrew the gearbox plug.
- Apply a new lubricant: insert a syringe with a tube into the hole and squeeze out the lubricant (2-5 ml).
- We turn the shaft manually, turn on the scythe at low speed without load. This is necessary in order for the lubricant to be efficiently distributed in places subject to maximum friction.
Lower and upper gear lubrication
There are tips that recommend lubrication at the end of the season. However, most people find it best to do this at the beginning of each season. When we repair a unit, as well as carry out any disassembly, it is necessary to use lubricants. The gearbox needs additional lubrication when the old trimmer is inserted.
Modern trimmers are equipped with a gearbox that measures the angle of transmission of mechanical energy between two components: the shaft and the head. Bevel gears are considered common, they can easily withstand high speeds, are equipped with smooth engagement, as well as an increased level of bearing capacity. The housing includes a shaft, a gear wheel, which is pressed onto the driven shaft. In order to reduce friction, bearings are installed on the bearing points of the shaft.
Prevention and possible malfunctions of the gearbox
the lawn mower requires the first preventive maintenance immediately after purchase, because the manufacturer puts in a small amount of lubricant. If the trimmer does a small amount of work, then lubricate the device at the beginning and end of the season. If the lawn mower works a lot, then we lubricate it after 30-55 hours of operation.
If the lubrication is insufficient, then it is completely changed. Manufacturers are trying to produce universal chemicals that are suitable for the processing of various hoses and assemblies.
The main malfunctions include the most common options.
- Strong heat. This indicates that the lubrication has run out. It is necessary to add lubricants and run them in at low mode.
- Gearbox vibrates or wobbles. This situation indicates mechanical damage.
- There is a knock. Then the bearing collapsed, the boot is damaged.
- If the trimmer knife is jammed, then the mechanism should be changed completely.
How to properly lubricate the gearbox of lawn mowers, see below.