To quickly and without extra effort put in order country cottage area or local area, use brush cutters. Their most intensive use occurs in the warm season. Before work, make preparations - lubricate moving parts, check and replace cutting accessories, refuel fuel mixture. Not everything always goes smoothly - the engine may not start or stall almost immediately. To identify and repair faults, look at the attached documentation. The article will discuss the repair of lawn mowers, with photos and illustrations, as well as its most common malfunctions.
Petrol mower device
The main element is the engine internal combustion, as a rule, two-stroke. Connected to it through a gearbox is a shaft that transmits force to the cutting headset and is covered by a tubular rod. Cutting part in the form of knives or fishing line rotates at high (10-13 thousand rpm) speed. On protective casing provided technological holes for supplying lubricant. For comfortable use, the brush cutter is equipped with a belt.
There are two types of cutting elements:
- Line with a cross section of 1.6-3 mm for the trimmer head. During operation, the fishing line wears out, and either the bobbin with fishing line is replaced, or the fishing line is rewinded and replaced.
- Double-edged steel knives for cutting small bushes, or thick and dense vegetation. The difference between them is both in shape and sharpening.
The handle attached to the bar is equipped with buttons and levers for controlling the lawn mower. A protective casing is installed on the cutting mechanism.
Refueling is carried out into an existing tank, mixed in the required proportions with gasoline and oil, and gasoline is used with an octane number of at least 92. Gasoline mowers with a four-stroke internal combustion engine are refueled differently - gasoline is refueled separately, oil is poured into the crankcase separately.
It is impossible to start the engine - reasons
The first thing to do is check whether there is gasoline in the tank, and if so, what quality it is. The use of low-quality or low-octane gasoline leads to failure of the piston system. Repairing a piston trimmer will cost almost half of its total cost. Also important correct proportion gasoline and oil, given in the attached operating instructions for the tool.
Making a large amount of the mixture is undesirable, since it becomes unusable over time. You should not use an old mixture that has been standing for some time.
The engine may not start if the fuel filter is seriously clogged. If it is severely clogged, it must be replaced. Do not use the trimmer with the fuel filter disconnected. The air filter may be clogged. In this case, it is washed with water and detergent and dried, or in extreme cases, soaked in gasoline. After installation, the dried filter is moistened with the oil used in the mixture.
If after the above measures the internal combustion engine does not start, it is adjusted to Idling using the screw on the carburetor.
Quick start of the brush cutter
The procedure is as follows:
- Place the lawn mower with the air filter facing up, remove it and pour a little mixture into the carburetor, and put the filter back on.
- If after the above procedure it is not possible to start the brush cutter, you need to check the spark plug. The internal combustion chamber is dried and the spark plug is replaced with a working one.
- If the spark plug is working, proceed as follows. Close the air damper on the carburetor and pull the starter handle. Open the damper and pull the handle 3-4 times. The process is repeated several times.
Spark plug malfunction - action algorithm
They act this way:
- let the engine sit to cool down;
- remove the wire from the spark plug high voltage and unscrew it with a special key;
- after inspecting the spark plug, it is replaced if it is heavily soiled, there is a crack in the body or any other malfunction;
- check the gap between the electrodes, it is ideally 0.6 mm;
- clamp the new spark plug using a special key;
- connect a high voltage wire to the spark plug.
The lawn mower stalls after starting
The probable cause of the failure is a problem in the lawn mower's carburetor. A sign of this is that the tool vibrates strongly during operation. They do this - they adjust the carburetor according to the diagram specified in the documentation.
Another reason is a clogged fuel valve. They clean it. It may be difficult to supply the mixture to the carburetor, and then the lawn mower will suddenly stall. In such cases, the carburetor valves are loosened.
When too much air enters the system, the lawn mower also stalls. It is necessary to increase the engine speed and squeeze out the air, and also check whether the fuel hose is damaged. If defects are found, it is replaced.
Timely and proper care for a lawn mower is the key to its trouble-free operation for several seasons. It is better to spend a little time on prevention than much more on repairs, not to mention wasting money.
Photo of repairing a lawn mower with your own hands
Surely any summer resident or owner of a private home has at least once thought about buying a tool such as a gas trimmer (also called a gas trimmer). And this tool is really useful, because thanks to it you can very quickly bring your land plot in order. This equipment is purchased in order to mow the grass in your garden.
Typically gas trimmers are used in summer period. Before using the tool, it is necessary to bring it into working condition, that is, lubricate all parts, change cutting accessories, and also fill the fuel mixture into the tank.
But such an unpleasant situation may arise when the engine does not want to start at all and immediately stalls, it is not able to rev. a large number of rpm In this case it is necessary find the causes of the problem and eliminate all problems.
Not all people have dealt with such equipment before, and therefore are wondering how to repair a trimmer with their own hands. To repair a lawn mower yourself, you need to understand its structure, as well as the principle of operation.
This information is usually provided in the special instruction manual, which is given upon purchase. You need to check its availability before purchasing a lawn mower. If you purchased an imported instrument, then the instructions should still be written in Russian, otherwise it is better not to buy such a device and look for one that you can figure out without the help of the Internet and a translator.
A long rod is attached to the gearbox of a two-stroke internal combustion engine. Inside the rod there is a shaft, through which torque is transmitted from the motor to the cutting part.
The fishing line or knife rotates at a frequency of approximately 10000−13000 rpm. The protective housing of the gearbox has holes into which lubricant is supplied using a special syringe. To make it convenient to use the tool, it is equipped with a special strap that can be thrown over the shoulder.
In order to be able to use the device, you must purchase the appropriate headset.
Thick fishing line from 1.6 to 3 mm, which is independently located in the trimmer head. When mowing the grass, the fishing line will be subject to a lot of wear, and therefore it is advisable to purchase it in a large roll. The replacement will be done in a fairly easy way: you can wind it with the same diameter on a bobbin or simply install a new reel, which is already sold with ready-made and correctly wound fishing line.
If you change it manually, then first carefully look at how it was originally attached in order to exactly repeat the winding. To charge properly new thread, you need to measure the installed piece and fold it so that one end is 15 cm longer than the other. The loop should be inserted into the slot that is on the reel, and then begin to wind the fishing line in the direction of the arrow.
Knives that installed for mowing weeds, small shrubs or coarse grass. Knives have different shapes, and their number may vary depending on the purpose.
If there is a U-shaped, D-shaped or T-shaped handle, then there should be located on it device control levers. The cutting mechanism is protected using a special casing. It is necessary to refuel lawn mowers with a mixture of oil and gasoline; it is poured into the tank. Construction of semi-professional and household scythes equipped with a four-stroke gasoline engine, will be slightly different.
The refueling scheme will also change a little, since in the first case oil will have to be poured into the crankcase, and gasoline into the tank. In the second option, gasoline and oil are mixed in the prescribed proportions and poured into the tank.
If the engine does not start
When the lawn mower does not start, you must first check to see if the fuel in the tank has run out. If everything is in order, then you need to check its quality - perhaps you purchased a cheap type of gasoline that is not suitable for the equipment. For the scythe, it is best to use good gasoline, which is purchased at gas stations; the grade should be at least AI-92.
You should not save money and buy cheap fuel, as this will lead to the cylinder-piston group will fail, but you can spend a lot on repairs more money than high-quality gasoline.
And also very important prepare the fuel mixture correctly and combine oil and gasoline in the right amount. The proportional ratio must be specified in the manual. That is why it is so important that it be written in Russian, because there is a possibility that different models A mower requires several different proportions to function successfully.
There is no need to use the fuel mixture in large volumes, since if the unused volume is stored indoors for a long time, it will lose its properties. It is better to use a freshly prepared solution.
- A problem with engine operation can be contamination of the fuel filter. First of all, you have to check the filter. If necessary, replace it. Under no circumstances should the inlet pipe be left without a fuel filter. It’s also worth checking the air filter at the same time. If it gets dirty, you need to remove it, wash it in gasoline and put it back in place. If you are at the dacha or in a private house, then it will be enough to rinse it in clean water using various detergents. After this, rinse, wring out and let dry. The finished filter is moistened in a small amount of oil, which is used to prepare the mixture. Excess is removed by squeezing the filter with your hands. Then the part can be put back.
- If all these procedures did not help and the engine still does not start, then you can try to adjust the idle speed, to do this, start tightening the carburetor screw. This is very similar to tuning a similar part on a car. If you have no experience in adjusting the carburetor, then you can study videos on the Internet, which are very clear and accessible. There they will clearly show how you can produce.
Quick start of the unit
Correct replacement of spark plugs
Many people know that spark plugs should be changed periodically, but few do it correctly and in a certain sequence. To perform all the manipulations correctly, you should familiarize yourself with in the right order actions.
In this procedure there's nothing complicated, and absolutely any owner of a gasoline scythe can cope with it.
The lawn mower stalls after starting
The engine may stall after starting the device if the carburetor is not configured correctly or is misadjusted. It's very easy to identify. Vibrations may occur and are clearly felt during operation. You can make the adjustment yourself; you should strictly follow all the instructions written in the manual.
The engine may also stall due to fuel valve clogged. In this case, it must be cleaned, and then the problem will be eliminated.
If the scythe starts up and then suddenly stalls, this means that the supply of fuel to the carburetor is difficult. Necessary loosen carburetor valves, then the free approach of fuel to it will be carried out in required quantity.
If there is excessive air leakage, then the engine may also stall. Should add a little revs to allow air bubbles to escape from the fuel system. It is also worth checking the integrity of the fuel intake hose. If any damage is found in it, the part must be replaced immediately.
Storage and cleaning of tools
You can always ensure that any equipment is cleaned after use. All channels in the starter housing, as well as the cylinder fins, must be absolutely clean. If this requirement is ignored, this will lead to equipment failure.
Always allow the engine to cool before cleaning. Take a brush that has soft bristles and clean the entire outer surface of dirt. We treat plastic parts with a solvent, including kerosene, and you can also use detergent.
When summer season running out, lawn mower needs to be prepared for canning. To do this, drain the entire fuel mixture from the tank. The engine starts to burn out any remaining fuel in the carburetor. Clean the instrument well and place it in a dry place.
There are many companies that produce such equipment. These include the Husqvarna, Huter, and Shtil gas mowers. There are domestic or Chinese options lawnmowers with different calibers, but, by and large, they are designed similarly. Once you figure out why one failed, it will be easier to fix the breakdown on a new model, and therefore the repair experience is very useful and allows you to save money.
As you can see, you can repair a lawn mower yourself, and for this you only need correctly establish the cause, which is not so difficult to eliminate. The service will charge a lot of money for this. So much that it’s easier to just buy a new lawn mower. Therefore, there is always the opportunity to understand the design and make repairs yourself.
At first glance, a simple device for mowing grass using a two-stroke engine has fine tuning. Repairing a lawn mower should be entrusted to a specialist or you should study the equipment yourself using the instruction manual. Maintenance Braids need to be maintained. Lubricating the gearbox, replacing the fishing line, and sharpening the teeth can be done on your own.
Petrol mower malfunctions and how to fix them
Any type of lawn mower has a hollow rod in which a connecting cable is placed between the engine shaft and the lower gearbox, which transmits rotation to the working element with cutting tool. At the top there is a carburetor and a motor, at the bottom there is a gearbox and a working tool covered with a casing. In the middle part there is a transverse handle in which control buttons are located. To unload the hands, there is an unloading belt that holds the bar with the operator’s torso.
When choosing a lawn mower, it is preferable to have a device with a two-stroke engine rather than a four-stroke one. A two-stroke engine is more maneuverable and easier to repair. With a four-stroke unit, the vibration level is lower.
They follow this, repairing a lawn mower consists of troubleshooting,
- the engine does not start,
- the cutting mechanism does not gain momentum,
- the engine stalls
- the gearbox gets hot,
- an extraneous knock is heard, strong vibration of the rod.
Before troubleshooting, you need to diagnose and identify the non-working unit.
It is important to know the lubrication points of the tool. Regular care and cleaning of the device after use will extend its service life. Before work, you need to tighten the mounting bolts, prepare fuel and fill the tank.
Chainsaw engine does not start
If the mechanism does not start, it stalls immediately, check sequentially:
- is there fuel in the tank,
- spark plug serviceability,
- cleanliness of the air and fuel filters,
- cleanliness of the breather and exhaust channel.
It is necessary to refill with a freshly prepared mixture based on AI-92; the oil is injected for precise dosage with a medical syringe. This will help avoid expensive repairs chainsaws.
You need to make sure that the spark plug is working and produces a spark when it comes into contact with the body. In this case, it is necessary to dry the spark plug channel, clean and dry the part itself. You can change the candle, but the channel still needs to be dried for 40 minutes. Check the serviceability of the high-voltage wire; there may not always be contact. A malfunction in the ignition unit when repairing a lawn mower cannot be repaired with your own hands.
If when removed air filter and the engine does not stall, the reason is that it needs replacement or cleaning. The fuel filter is replaced with great care. After checking the cleanliness of the breather, remove the muffler mesh and clean the exhaust channel.
The next step will be carburetor repair, where you will have to find the fault and fix it, taking into account the tiny size of the parts. If the simplest operations do not bring results, in order not to disrupt the fine tuning of the system, it is better to entrust the repair to a specialist. Where to start diagnosing and how to properly repair a lawn mower with your own hands, watch the video:
Repair and lubrication of the lawn mower gearbox
The role of the gearbox is to transmit torque from the motor shaft to the cutting tool through 2 toothed gears with different amounts teeth Torque is transmitted at an angle of 30. Lower speed cutting disc 1.4 times less engine speed. Gears must be clean and lubricated. There is a hole under the screw on top to supply oil to the teeth.
The lawnmower gearbox is lubricated at least once a season. If the work is intensive or there is extraneous noise in the lower unit, it is necessary to lubricate more often.
First, you should clear the area where the plug covers the hole from soil and grass. Unscrew the plug with the appropriate tool, it is included with the saw. We use grease from a tube. Select either a native lubricant from the manufacturer, or well-known high-quality compositions, such as Oleo-Mas, Litol -24, Azmol 158. We open protective layer tube and place the instrument on its side. Slowly rotating the knife, squeeze the lubricant into the gear housing. The gears, turning, spread the composition with teeth over the entire surface. You can also add lubricant using a special syringe.
Too little or too much lubrication can cause the gearbox to heat up. An audible knock and play indicate the destruction of the bearing or the ingress of dirt due to damage to the anthers. Bearings must be replaced using a puller, without using the heating method.
If the gearbox wobbles and moves along the rod, it is necessary to replace the housing, or temporarily tighten the assembly with a clamp to secure it to the pipe. If the knife stops rotating, it means that the gears are not engaging - the teeth have become worn out or chipped. The pair will need to be replaced with complete disassembly of the unit.
Disassembly of the gearbox with removal of the shaft and bearing units cannot be carried out using heat. When heated, the metal loses its strength qualities and subsequently the unit becomes unreliable. To remove bearings, use a puller.
When replacing a gearbox, it is necessary to select a new unit, guided by:
- pipe diameter,
- drive shaft diameter,
- cross-section of the drive shaft,
- method of securing protection
Caring for cutting units of lawn mowers
The saw set becomes dull or wears out over time. Working with the tool becomes stressful, the load increases, and the quality of the swath deteriorates. Metal saw blades sharpen, plastic ones are replaced.
If the cutting tool is a fishing line, it gradually wears out, and a new material. The principle of operation of a cutter with a fishing line is the gradual unwinding of the reel under the influence of centrifugal force. When in contact with grass, the fishing line wears out and is fed out of the reel gradually. Special winding is needed in order for two cutting element came out at the same time and did not get confused with each other.
The figure shows how to correctly wind the fishing line onto the reel of a lawn mower. Before winding a new fishing line you need to:
- unscrew the nozzle, carefully remove the cover, holding the spring with your hand,
- remove pieces of old fishing line from the reel,
- measure 5 meters of new string and fold it in half,
- there are guides in the reel for 2 ends, hook the middle part to the notch and wind in the direction of the arrows for each half of the string,
- pass the remaining 20 cm through special recesses at opposite ends of the coil,
- install the spring and washers, bring the ends of the fishing line out, close the drum with a lid.
To better understand how to change the fishing line on a lawn mower, watch the video.
Replacing fishing line in the trimmer head of a lawn mower - video
A personal plot will not have a neat appearance if bushes have grown in its gardening area and the grass has formed a thick cover. This indicates the neglect of the site by the owner, who does nothing even to mow the lawns. But mowing the grass is the easiest task on the site, because various equipment has been created for this work.
The advantage of a gasoline trimmer
For example, a trimmer is a very convenient and productive, lightweight, reliable and practical device to use. It can be electric, lightweight, or gasoline with high performance. Gasoline ones are more common, since they have a fuel tank and can operate at a distance from electrical communications. Perhaps the only negative petrol trimmer The fact is that, just like any equipment, it periodically fails. But in this matter it has an advantage, since for people who understand a little about technology, it is possible with their own hands.
Troubleshooting
If the trimmer stops starting, then you should not immediately sound the alarm and contact service center, since the cause of inoperability can be easily eliminated. Any DIY repair of gasoline trimmers begins with checking for the presence of a spark, without which it is impossible to ignite the fuel in the combustion chamber. If there is no spark, then the problem is either in the spark plug or in the ignition itself. An exception is in cases where the spark plug is filled with fuel mixture when the fuel is overfilled above the required level. In this case, you just need to wipe it dry and the treasured spark will appear.
It will also indicate that there is no fuel supply. If it is dry and light brown in color, in this case, repairing a gasoline trimmer with your own hands will involve adjusting the fuel pumping or All these reasons can be easily eliminated, the main thing is that the engine itself works properly. But if the cause of the malfunction is still hidden in the engine itself, then it is recommended to contact a service center due to the complexity of repairs. But for people who can hold a screwdriver in their hands, nothing is impossible. In most cases, trimmer ends successfully.
Briefly about engine repair
Engine problems begin after a few years correct operation from wear of components or suddenly due to improper use of the trimmer. Unfortunately, people regret improper operation when they repair gasoline trimmers with their own hands after an engine breakdown. And this happens in cases where the dosage of oil in the fuel is not observed or the device operates to the point of terrible overheating. Overheating may cause the crankshaft to jam, the piston rings to break, or the piston to completely burn out. In order to perform a piston inspection, it is enough to remove the cylinder head, from under which a piston will appear, clearly reflecting the condition of its work surface. The rings themselves do not protrude from the cylinder, so it does not matter whether you change the rings or the piston, in both cases you will have to remove the cylinder. When repairing gasoline trimmers with your own hands, it is worth remembering that they are fragile and can easily break if you lack experience. Installing the piston itself on the crankshaft is not too difficult. The main thing when repairing an engine is to assemble everything the same way as it was before disassembly, and then everything will work again.
At first glance, a simple device for mowing grass using a two-stroke engine has fine tuning. Repairing a lawn mower should be entrusted to a specialist or you should study the equipment yourself using the instruction manual. Maintenance of the scythe is necessary. Lubricating the gearbox, replacing the fishing line, and sharpening the teeth can be done on your own.
Petrol mower malfunctions and how to fix them
Any type has a hollow rod in which a connecting cable is placed between the motor shaft and the lower gearbox, which transmits rotation to the working body with the cutting tool. At the top there is a carburetor and a motor, at the bottom there is a gearbox and a working tool covered with a casing. In the middle part there is a transverse handle in which control buttons are located. To unload the hands, there is an unloading belt that holds the bar with the operator’s torso.
When choosing a lawn mower, it is preferable to have a device with a two-stroke engine rather than a four-stroke one. A two-stroke engine is more maneuverable and easier to repair. With a four-stroke unit, the vibration level is lower.
They follow this, repairing a lawn mower consists of troubleshooting;
- the engine does not start;
- the cutting mechanism does not gain momentum;
- the engine stalls;
- the gearbox gets hot;
- an extraneous knock is heard, strong vibration of the rod.
Before troubleshooting, you need to diagnose and identify the non-working unit.
It is important to know the lubrication points of the tool. Regular care and cleaning of the device after use will extend its service life. Before work, you need to tighten the mounting bolts, prepare fuel and fill the tank.
Chainsaw engine does not start
If the mechanism does not start, it stalls immediately, check sequentially:
- is there fuel in the tank;
- serviceability of the spark plug;
- cleanliness of the air and fuel filter;
- cleanliness of the breather and exhaust channel.
It is necessary to refill with a freshly prepared mixture based on AI-92; the oil is injected for precise dosage with a medical syringe. This will help avoid expensive chainsaw repairs.
You need to make sure that the spark plug is working and produces a spark when it comes into contact with the body. In this case, it is necessary to dry the spark plug channel, clean and dry the part itself. You can change the candle, but the channel still needs to be dried for 40 minutes. Check the serviceability of the high-voltage wire; there may not always be contact. A malfunction in the ignition unit when repairing a lawn mower cannot be repaired with your own hands.
If the engine does not stall when the air filter is removed, this is the reason - replacement or cleaning is required. The fuel filter is replaced with great care. After checking the cleanliness of the breather, remove the muffler mesh and clean the exhaust channel.
The next step will be where you have to find the fault and fix it, taking into account the tiny size of the parts. If the simplest operations do not bring results, in order not to disrupt the fine tuning of the system, it is better to entrust the repair to a specialist. Where to start diagnosing and how to properly repair a lawn mower with your own hands, watch the video:
Repair and lubrication of the lawn mower gearbox
The role of the gearbox is to transmit torque from the motor shaft to the cutting tool through 2 toothed gears with different numbers of teeth. Torque is transmitted at an angle of 30 0. The speed of the lower cutting disk is 1.4 times less than the engine speed. Gears must be clean and lubricated. There is a hole under the screw on top to supply oil to the teeth.
The lawnmower gearbox is lubricated at least once a season. If the work is intensive or there is extraneous noise in the lower unit, it is necessary to lubricate more often.
First, you should clear the area where the plug covers the hole from soil and grass. Unscrew the plug with the appropriate tool, it is included with the saw. We use grease from a tube. You choose either a native lubricant from the manufacturer, or well-known high-quality compounds, such as Oleo-Mas, Litol-24, Azmol 158. Open the protective layer of the tube and lay the instrument on its side. Slowly rotating the knife, squeeze the lubricant into the gear housing. The gears, turning, spread the composition with teeth over the entire surface. You can also add lubricant using a special syringe.
Too little or too much lubrication can cause the gearbox to heat up. An audible knock and play indicate the destruction of the bearing or the ingress of dirt due to damage to the anthers. Bearings must be replaced using a puller, without using the heating method.
If the gearbox wobbles and moves along the rod, it is necessary to replace the housing, or temporarily tighten the assembly with a clamp to secure it to the pipe. If the knife stops rotating, it means that the gears are not engaging - the teeth have become worn out or chipped. The pair will need to be replaced with complete disassembly of the unit.
Disassembly of the gearbox with removal of the shaft and bearing units cannot be carried out using heat. When heated, the metal loses its strength qualities and subsequently the unit becomes unreliable. To remove bearings, use a puller.
When replacing a gearbox, it is necessary to select a new unit, guided by:
- pipe diameter;
- drive shaft diameter;
- drive shaft cross section;
- method of securing protection
Caring for cutting units of lawn mowers
The saw set becomes dull or wears out over time. Working with the tool becomes stressful, the load increases, and the quality of the swath deteriorates. Metal saw blades are sharpened, plastic ones are replaced.
If the cutting tool is a fishing line, it gradually wears out and new material is installed in the reel. The principle of operation of a cutter with a fishing line is the gradual unwinding of the reel under the influence of centrifugal force. When in contact with grass, the fishing line wears out and is fed out of the reel gradually. Special winding is needed so that two cutting elements come out at the same time and do not get confused with each other.
The picture shows how to properly wind the fishing line onto a reel. Before winding a new fishing line you need to:
- Having unscrewed the nozzle, carefully remove the cover, holding the spring with your hand;
- remove pieces of old fishing line from the reel;
- measure 5 meters of new string and fold it in half;
- there are guides in the reel for 2 ends, hook the middle part to the notch and wind in the direction of the arrows for each half of the string;
- pass the remaining 20 cm through special recesses at opposite ends of the coil;
- install the spring and washers, bring the ends of the fishing line out, close the drum with a lid.
To better understand how to change the fishing line on a lawn mower, watch the video.
Replacing fishing line in the trimmer head of a lawn mower - video