Even professional chainsaws from around the world famous manufacturers break - no one is immune from this. The question is how often breakdowns occur and how serious they are. It’s one thing when you need to sharpen the chain or replace the drive sprocket, and another thing when the chainsaw doesn’t start or shoots into the carburetor. In fact, most of the problems can be fixed with your own hands, for example, when the chainsaw does not lubricate the chain or stalls.
No. 1. Chainsaw won't start
If difficulties arise with starting a chainsaw, many immediately sin. In fact, there are several options and the cause of the malfunction can be any: 
- Air and/or fuel filters are clogged. The problem can be solved by cleaning the filters.
- Lack of fuel in the tank. Yes, there is such a reason - some owners forget about such an insignificant detail as refueling a chainsaw and think that a couple of liters of gasoline will last for six months. In addition, fuel in the tank should not be stored for more than 14 days, because gasoline evaporates and the octane number is lost.
- Check the pipe from the fuel tank to the carburetor - it could be clogged or broken, so gasoline does not flow into the tank.
- There is no spark at the spark plug. Why there is no spark - there can be many reasons: there is no contact, the spark plug needs to be changed or it is flooded. Why the spark plug on a chainsaw fills is another question. But if this happens, you need to dry it and reinstall it, and then check for a spark. If there is heavy carbon deposits on the spark plug, it is recommended to replace it.
- Check the muffler for carbon deposits. If there is carbon deposits, thoroughly clean the muffler, but it is still recommended to take the chainsaw to a service center to have the cylinder and piston checked, because carbon deposits are a sure sign of improper operation of the elements of the cylinder-piston group.
- The carburetor is clogged. How to properly adjust a chainsaw so that the carburetor works well is discussed in a separate article.
If none of the above methods helped, then the reason is more serious - a breakdown of one of the connecting rod-piston group units. In this case, it is recommended to take the chainsaw to a service center.
No. 2. The engine stalls
The engine starts, but the chainsaw stalls at idle or under load. In this case, most often you should perform the same actions as described above.
How to adjust a chainsaw depends on exactly when the problems start:
Stalls immediately after starting:
- The fuel mixture is not prepared correctly, there is too much oil in it, so the octane number of gasoline is less than it should be, so the chainsaw only runs on choke or stalls immediately.
- Carbon deposits on the spark plug or improper gap between the spark plug and the wire.
It stalls and does not work at idle:
- The muffler is clogged. It is necessary to remove carbon deposits.
- The carburetor settings have gone wrong. The idle speed on the chainsaw needs to be adjusted. This is done using adjusting bolts marked L and H. For how to adjust idle speed, see the article about adjusting the carburetor.
Stalls at maximum speed and only runs on choke
- The air or fuel filter is clogged. The seals need to be cleaned and checked.
- The breather is clogged and because of this, fuel does not flow and pumping gasoline on the chainsaw does not work. Take the needle and carefully clean the breather.
- Fuel pump malfunction. Remove the pump and check to see if gasoline is leaking from it. If it oozes, replace the sealing gasket or the pump itself.
The chainsaw does not cut under load and stalls
- The air filter is clogged. It is necessary to take out the filter, clean it well or even rinse it, dry it and put it back.
- Wrong proportion of oil/gasoline mixture. Drain the fuel and remix the oil and gasoline in the correct proportions.
No. 3. The engine "shoots"
If during operation there are extraneous sounds similar to gunshots, then there is a problem with the muffler or carburetor. How to make a chainsaw run quietly? It depends on which node is faulty.
Shoots the carburetor:
- Ignition is too late - the air-fuel mixture does not have time to burn out in the cylinder, so the sound is similar to a small explosion.
- Lean air-fuel mixture. Too little gasoline enters the mixture - the chainsaw, or rather the jets, needs to be adjusted to increase the fuel supply. Why the chainsaw revs on its own is for the same reason.
Shoots at the silencer:
- Enriched air-fuel mixture. Why does a chainsaw “shoot”? There is too much gasoline and not enough air in the mixture, so the mixture does not completely burn out in the chamber and partially burns out in the muffler. Carbon deposits on the exhaust are a clear sign of this. Needs cleaning air filter or carburetor adjustment.
No. 4. Chainsaw overheating
Why does the chainsaw get hot? The engine or tire may overheat - in any case, the fault is due to a small amount of lubricant.
- Engine overheating. Incorrect proportion of fuel mixture or even pure gasoline is poured. Drain the fuel and make a mixture using the correct proportions of oil and gasoline as specified by the manufacturer.
- Tire overheating. The oil pump needs to be cleaned or adjusted because... No oil is supplied to the tire.
No. 5. The chain doesn't cut
A decrease in chainsaw performance is associated with dull chain teeth. This is the most common problem because... sharpening must be done regularly. How to do this using a machine, file or grinder, read the corresponding article.
No. 6. The chainsaw cuts to the side
When cutting, you may notice that the result is an uneven cut. Why does a chainsaw cut crookedly? There are several reasons:
- Incorrect chain sharpening. The teeth are sharpened at the wrong angle or only in one direction. Proper sharpening is required.
- Incorrectly selected chain. At very high speeds, a difference of even 0.2-0.3 mm between the width of the groove or the width of the seat will be visible, which is why the chainsaw cuts to the side. An appropriate circuit must be installed.
- Uneven tire wear. Over time, the tire wears out on one side and then the chain moves to the side. Rotate the tire regularly to ensure even wear on both sides. If the wear is excessive, replace the tire.
No. 7. Chain lubrication problems
For normal operation The chain must be constantly lubricated to reduce friction between the bar and the links, and also to prevent premature wear of the links.
- If the chain on the chainsaw is not lubricated, then there is a problem with the oil pump - oil is not supplied due to a clogged channel. Lack of lubrication is the reason why the chain stretches or why the chain breaks. Clean the channels; tiny particles of chips constantly get there and clog them. The oil hose may also break. If you need to adjust the chainsaw oil pump or repair it, it is better to contact a service center.
- Oil splashes from the chain. Incorrectly selected lubricant - it is too liquid, so it does not so much lubricate the links as it splashes onto the wood. Replace the lubricant with a thicker one.
No. 8. The chain falls off
Why does the chain fall off the tire? There may be several reasons and they are all different:
- Worn drive or driven sprocket. Due to the fact that the sprocket is worn out, the grip on the chain decreases, which is why the chain flies off the chainsaw. The sprocket needs to be replaced.
- The chain has stretched. Why the chain on a chainsaw stretches is due to insufficient lubrication. The metal heats up and stretches, even by a fraction of a millimeter, but if you take into account the number of links, then even 3-4 mm is enough for the chain to fly off the bar. The chain needs to be replaced.
- The chain tensioner that regulates its tension has become loose. how to regulate a chainsaw, or rather the chain tension? You need to adjust the tensioner - this can be done in just a few minutes.
No. 9. The chain does not rotate
Why doesn't the chainsaw chain rotate when the engine is running even at full speed?
- Leading sprocket. Either it is jammed, or the crown is worn out so much that it does not engage and the chain does not spin on the chainsaw. In any case, it is necessary to disassemble the sprocket to find out the exact reason why the chain does not spin. If the crown is worn out, it is necessary to replace the sprocket (or the crown itself, if the sprocket has a prefabricated structure).
- The chain brake is stuck. As a result, the sprocket is blocked by the brake mechanism, while the motor runs. It is necessary to turn off the engine and release the brake. If this happens under load, the brake mechanism will have to be changed, as well as the sprocket, because because of high temperature Many elements may melt and overheat.
No. 10. Chain brake does not work
All chainsaws are equipped with a main and inertial (emergency) brake. The latter turns on only when a backfire occurs. The main brake is designed to stop the chain while the engine is running. Why does the chain on the chainsaw jam and it doesn’t stop? There are two options:
- The brake band is badly worn and does not provide sufficient stopping effect. The brake band needs to be replaced.
- Contamination of the tape. When working, debris may become clogged in the under-cover space: shavings, sawdust, dirt, etc. Debris is blocking the brake mechanism, so if the brake does not work, you need to clean the brake mechanism.
DIY chainsaw repair and service
Prices for chainsaws are falling and this makes them more popular and accessible not only to experts, but also to ordinary, so to speak, amateurs. But the widespread dependence - the lower the cost, the less reliable the device and the more often malfunctions occur, is also vital for a chainsaw. But for a chainsaw of any price range, most of defects can actually be avoided when correct operation, care and timely technical maintenance technology. But no one is insured against the breakdown of a chainsaw, as well as any other equipment. Therefore, it is proposed to consider main types of chainsaw malfunctions, methods for diagnosing, eliminating and repairing them.
All the main malfunctions of chainsaws can be divided into two main categories:
- malfunctions of the engine and its various components: fuel preparation and supply system, ignition, piston group with crankshaft, exhaust gas system;
— malfunctions and breakdowns of other components: lubrication system, clutch, chain brake, tire and others.
Chainsaw engine malfunctions
Here are various malfunctions in the operation of a chainsaw engine that occur most often. These main malfunctions boil down to the following symptoms:
the engine does not start (quite general and the reasons can be quite different);
starts, but often stalls;
does not develop power, i.e. It runs fine at idle, but stalls or sputters under load.
It smokes a lot and the power drops.
Problems starting the engine
It is very important to correctly determine the cause of the malfunction, because otherwise we simply cannot eliminate it. There is a chainsaw, almost new, the engine works great, but the chain does not cut. If you give it gas, the engine reacts, but then tries to stall, because I’m not an expert on how to do it myself. By the way, the chain spins tightly, but the chain doesn’t work. The chain is not on the bar. If, when trying to start the chainsaw, there are no extraneous sounds (knocking, grinding, etc.), then very often it turns out that in fact there is no breakdown. For example, if you start the chainsaw incorrectly and pull the choke for a long time, the engine simply floods and it is very difficult to start it.
In order to properly start a cold chainsaw engine, set the lever or switch to the shutter position. Then you need to pump the mixture into the carburetor, if there is a fuel priming pump. Pull out the starting handle until the engine resistance becomes noticeable, and vigorously pull in amplitude, moving your hand to the side. After two or three such movements, the engine should first start and then stall. If this does not happen, then you need to move the lever to the half-throttle position or simply to the working position and then continue to start the chainsaw in this mode. For many chainsaws, the “half throttle” is automatically locked when the air damper is pulled out. Some models have rocker switch ignition, it is important to make sure that it is turned on.
If the engine does not start, then the first thing to do is unscrew and inspect the spark plug. At idle, the chain should not move; the chainsaw will lose power or not. There are cases when at a plant in the cold season, the combustion chamber is filled with fuel. Then you also need to unscrew the spark plug, dry the combustion chamber by idling, clean the spark plug, screw it in and repeat the start. If the chainsaw pump does not work, the chain will not spin as a result. It is advisable to immediately check for the presence of a spark - put a cap with a high-voltage wire on the unscrewed spark plug, place it on the cylinder and pull the starter. Visually we observe a frequent blue spark - good. Screw the spark plug into place and start it. If there is no spark, change the spark plug and try again. No again - we check the connection of the high-voltage wire to the spark plug, the coil and the ignition system.
In general, the type of malfunction can be judged by the condition of the spark plug.
- Dry. Most likely, the fuel mixture is not getting into the cylinder. The problem is not in the ignition system, so screw the spark plug back in and check the fuel supply system.
- Wet, heavily splashed with fuel. The reason for the excess fuel mixture lies either in a violation of the starting rules, as described above, or in incorrect carburetor adjustment.
- Covered with black soot. This may indicate the use of low-quality oil, an incorrectly adjusted carburetor, or an incorrectly calculated ratio of gasoline to oil. The spark plug should be washed, removed from carbon deposits with a sharp object (an awl or a needle), the electrodes should be wiped with sandpaper and placed in place.
When checking the spark plug, you need to pay attention to the gap between the electrodes: 0.5 to 0.65 mm is considered normal. A damaged or worn gasket must be replaced.
Checking and adjusting the chainsaw carburetor
A properly adjusted chainsaw carburetor ensures that it operates efficiently at full power with the most economical fuel consumption.
Read also
The need to adjust the carburetor of a chainsaw arises infrequently, since the adjustment is initially carried out by the manufacturer to achieve optimal mode work. The adjusting screws are designed for more precise adjustment of the chainsaw carburetor if necessary.
When and why does this need arise?
Among the reasons for the failure of fixation of the adjusting screws, the most common are the following:
- Severe vibration or damage to the protective cap. This happens rarely, but it does happen.
- Serious engine wear (piston). Of course, in this case it is worth taking more care of repairing the chainsaw engine, but still adjusting the carburetor can improve its functionality for a while.
- Blockage in the carburetor due to damage to the air filter, poor quality gasoline or due to the formation of scale. In this case, in addition to adjusting the carburetor, flushing it cannot be avoided.
The chain on the chainsaw/on the brake does not spin/consequences
Let's look at the consequences of use chainsaws with the brake on. AND general recommendations benzo care.
The chain on the chainsaw is jammed, we are looking for the cause. Part 1.
We remove the sprocket and at one time look at the condition of the oil pump Link to mine.
What signs indicate the need to adjust a chainsaw carburetor?
- Firstly, the engine does not start, or it starts, but immediately stalls. This most often occurs due to a lean fuel mixture.
- Secondly, a significant increase in fuel consumption and exhaust emissions. An increase in exhaust emissions indicates that the fuel does not burn completely, which means that the cause may be oversaturation of the fuel mixture.
The chainsaw carburetor adjustment scheme may differ slightly depending on the manufacturer (the process of adjusting the chainsaw carburetor of a specific brand and model is described in detail in the operating instructions), but general principles remain the same for all brands. The purpose of adjusting the saw is to change the quantity and quality (richness) of the fuel mixture supplied to the engine cylinder.
To learn how to adjust the carburetor on a chainsaw, you should learn to distinguish between three screws (some models have only one).
Screws L and H are similar only in appearance, in fact they are different
Each screw has its own letter designation:
- “L” is used to adjust low speed;
- “H” is necessary to adjust the upper speed;
- “T” is needed to adjust the idle speed (models with one screw only have it).
Exist mandatory requirements safety precautions that must be observed when adjusting the carburetor of any chainsaw:
- Make sure the chain is facing away from you.
- The saw must be firmly positioned on flat surface, and its cutting part should not touch any objects.
Note: exact values You will find the rotation angle of the adjusting screws in the operating instructions specific to your chainsaw model. Carefully following the manufacturer's instructions will help you avoid engine damage.
The process of setting up a chainsaw carburetor consists of two stages: basic (engine off) and final (warm engine running).
Basic adjustment of a chainsaw carburetor
Slowly turn the maximum and minimum speed adjustment screws (H and L) clockwise until they stop, then turn them counterclockwise 1.5 turns.
Final adjustment of the chainsaw carburetor
Idle speed adjustment
Before this adjustment step, it is necessary to warm up the engine for 5-10 minutes, avoiding high speeds.
Read also
By turning the idle speed adjustment screw (T/LA/S) counterclockwise, achieve the minimum speed at which stable engine operation will be ensured. Make sure the chain does not move. But no more than 1/8 of a turn. But on the packaging such information is not difficult to select a new chain; the blade is lubricated. The chain does not spin; and when your chainsaw doesn't work. That is, if the engine stops at idle, turn the idle speed adjustment screw clockwise. If the chain is driven, turn the screw counterclockwise.
To complete the adjustment of the chainsaw carburetor, you need to check the engine for acceleration and maximum speed.
Acceleration check
To check the engine for acceleration, gently press the accelerator and make sure that the engine quickly picks up speed from idle to maximum speed (from 2800 to 11500-15000 revolutions - depending on the brand and model of the saw). But even this technique with a chainsaw only works but the chainsaw does not cut. If the engine picks up speed slowly, slowly turn screw L counterclockwise (no more than 1/8 turn).
Adjusting the maximum speed
Adjustment maximum number revolutions are made using screw H. The revolutions increase when it is turned clockwise, and decrease when it is turned counterclockwise.
Electric saws are preferred for one good reason - they are very light and therefore easy to use. Of course, you won’t go far into the forest with her, - network cable won't let me in. But for use near the house (for sawing logs, preparing firewood, pruning trees, during construction and repairs) the best tool can not found.
During operation, especially with frequent use, it begins to act up: it makes strange sounds, smells, does not brake on time or does not turn on at all. Nothing can be done - any technical device not forever. And every working day shortens his life. But there are breakdowns that only professional service can handle (for example, the case is damaged). And there are cases when you can resuscitate electric saw with your own hands, with effort, knowledge and skill.
We have made a selection practical advice How to repair a saw yourself without contacting a specialist.
Any breakdown does not occur out of nowhere. Its roots often lie in poor assembly and quality, or improper operation. If you buy quality tool from a reliable manufacturer, it is not so easy to “ruin” it. But still, most often malfunctions arise due to:
Power surges in the network. If the instrument has built-in fuses - protection against voltage surges, then it will withstand deviations from 220 V by 10% in one direction or the other. Not more. If there is no protection, the motor burns out.
Untimely lubrication. The vast majority of electric saws have automatic lubrication. Make sure you don't run out of oil. Remember that running “dry” is death for the motor. If oil does not automatically flow to the sprocket, then lubricate it yourself every 3-5 hours of operation.
Power overload. If it happens, it’s also your fault, not the manufacturer’s. If it is stated that you can cut logs up to 5 cm in diameter, then cutting a ten-centimeter trunk is clearly overkill.
Design flaws. This is already an oversight by the manufacturer. The most common disadvantage is the rigid coupling of the gearbox with the anchor. When transferring a strong load (dull belt or solid wood) it jams and gets hot. Gears wear out quickly. The way out of the situation is to sharpen it in time and avoid overload.
What you need to know before repairing
"Golden Rule self-repair- use only original parts and spare parts. If you try to install inappropriate elements of a different brand and configuration, then this is a 100% guarantee of future breakdown and failure of the electric saw.
Before you repair a tool, create the necessary base for yourself. You will need:
1. Original factory parts from the same manufacturer.
2. Pliers, wrenches
3. Electrical tester, voltmeter.
4. Soldering iron.
5. Round and oval files, mandrel and sharpening gauge.
6. A machine for sharpening a chain (this is ideal, you can sharpen it manually).
What to do if the device shows no signs of life at all? If the saw does not turn on, it is possible:
- low voltage in the network. Measure with a voltmeter. If below 180, connect the equipment through a voltage stabilizer. Sometimes, when networks are installed, it is recommended to buy a good generator with an AVR, and power all power tools from it.
- the power cable is damaged. You need to check the cord and all connections. Replace or solder the gap and insulate.
- the start button does not work. Disassemble. Repair or replace. Sometimes, if the button is faulty, the power is turned on directly, but this option is not suitable for an electric saw - safety is critically reduced.
The chain brake has activated. Check it out. It turns on at a certain position of the brake element shield. The shield should be moved back a little.
- the thermal protection relay has tripped. Possibly if you turn on an overheated device. It needs to cool down, and perhaps the relay itself needs repair.
- carbon brushes are worn out. Frequent malfunction. Happens even in almost new instruments. Usually there is a loss of power first. Replace the graphite contacts with new ones.
- damage to the motor windings. The windings are destroyed due to overheating. Need to rewind. This is quite a complex process. It is necessary to disassemble the motor, remove the burnt winding and clean the insulation from the grooves. And then do everything yourself in reverse order. And to wind the coil, they use a winding machine. In general, if you are an electrical master, then go for it. If not, take it to service.
Often, when the saw is operating, the user hears an unpleasant, cutting sound in the ear, and smells a burning smell. This is what we talked about at the very beginning of the article - lack of oil in the mechanism. Check with a dipstick: if the crankcase is full, it means the conductive channels are dirty. Fixing the problem is simple - add oil or clean the furrows.
Quite often the instrument begins to “glitch” when stopped. It does not stop immediately, but after a while. The longer the saw is in use, the longer this time period becomes. To fix the problem, you need to replace the brake band. It's just worn out and stretched out.
Sometimes, while sawing, the device suddenly begins to vibrate strongly and lose power. You already know the reason - the brushes are worn out. If you do not replace it, the saw will soon stop turning on.
The chain does not rotate. Here possible malfunctions some:
- the teeth of the plastic gear are “licked off”. It is part of the gearbox and is the first to take the blow in case of critical overloads. And that's great! It is better to replace the gear than to throw away a burnt out motor or, worse, get injured. When replacing a worn one with a new one, lubricate the gear well with oil.
- wear of other parts (drive sprocket, cam, spring, clutch cup, bearing). Having identified a worn or crumbled part, replace it with an original spare part.
- chain tension is incorrectly adjusted. The situation occurs with both key and keyless tension. The instruction manual always describes how to properly tighten the chain and check its tension.
It's hard to believe, but almost half of the breakdowns occur due to a dull chain. It entails an increase in load on the motor, its overheating and premature wear. When the sawing band is dull, the gears of the gearbox, drive sprocket, bearings, etc. break.
The first sign of dullness is dark and fine sawdust. The teeth cannot remove the desired layer, so the chips are crushed. If you examine such a saw, you can see defects on the edge and even torn pieces.
Masters advise sharpening your saw as often as possible. If you delay this process, you will need to take the device to a workshop. Sharpening a file at home is possible using a special machine or manually.
If you sharpen regularly, you can do it yourself, following the rules:
- Sharpening should not be done directly on the ground, as dirt can clog the oil grooves.
- Use sharpening devices: files (circle and oval), mandrel and gauge.
- The sharpening angle should be greater than 30 degrees.
- The file should protrude slightly above the tooth.
- Sharpen the teeth one at a time, turning the tape.
- Having sharpened the teeth, using a gauge, you should straighten the cuts (protrusions that are responsible for deepening during the sawing process).
- If the cuts protrude slightly beyond the line of the teeth, then they can simply be filed off with a file.
As you can see, troubleshooting is easy, but also difficult. Remember that with proper operation and care, the need for repairs will occur much less frequently.
The most popular electric saws
When working with a chainsaw, in some cases you can notice how, when cutting a tree trunk with a diameter of more than 30 cm, the tire gradually begins to move to the side. This is especially noticeable when it is necessary to cut trunks large diameter, using the double-cut technique, i.e. first sawing from above, and then turning it over and finishing it to the end.
The logs, sawn off crookedly with a chainsaw, have uneven surface, this causes some discomfort when splitting them into logs. And the use of such a chainsaw when laying a log house, for example, for trimming bars, is not at all acceptable, since the ends will turn out uneven.
Discomfort during work, decreased productivity, increased fuel consumption, curved cutting, that's all Negative consequences of this phenomenon, but what is the reason?
There are actually only three reasons:
- Uneven sharpening of teeth;
- Using a chain that does not match the bus parameters or vice versa;
- Increased wear of the chainsaw saw set.
Uneven sharpening
According to the instructions, the teeth should be ground at the same distance, regardless of which side they are located on. By observing this simple requirement, you can protect yourself from problems associated with the fact that the chainsaw is pulled away when sawing.
Unevenly ground teeth are the most common problem with crooked cuts.
It is not always possible to control the length of a tooth using the technique of counting the number of movements with a file.
This is due to the fact that the wear of the teeth is uneven, some are more damaged and require large quantity movements with a file in order to bring them back to normal, which means the size of such teeth will decrease significantly compared to the others.
How to avoid incorrect sharpening
In order to prevent a crooked cut due to uneven sharpening, you can use a special tool to straighten the chain from time to time or in case of severe damage. sharpening machine. Buy a machine and sharpen it yourself or take it to a workshop for sharpening.
The fact is that during sharpening the machine is adjusted according to the most worn tooth, which has the smallest size among all. After sharpening is carried out, all teeth will have the same size, which will be equal to the tooth on which the adjustment was made.
The disadvantage of this method is that the life of the chain is significantly reduced, since even undamaged teeth have to be heavily ground down. Try to use the chainsaw more carefully, watch out for nails and any other metal products, which can come across when cutting old boards and other rubbish.
Using the wrong chain
It's no secret that, like a chain, it has several main characteristics, one of them is the width of the groove for installing the chain. The groove width can have several basic dimensions:
- 1.1 mm;
- 1.3 mm;
- 1.5 mm;
- 1.6 mm.
Let's imagine that we take a chain with a fit width of 1.1 and install it on a bar with a groove of 1.3 mm. Initially, having tensioned it well, we may not notice the differences, but as soon as the tension loosens a little, a gap of 0.2 mm will not allow it to move evenly along the tire, it will tilt to one side and we will again get crooked sawn material.
When purchasing a replacement chain for your chainsaw, give the exact dimensions, not the make and model of the chainsaw. Identical chainsaw models may have different tires installed and, accordingly, the chains will also be different.
You can check the width of the chain fit using a caliper.
To fix the problem, if the chainsaw bar is not yet badly damaged and there is no uneven wear on it, you only need to replace the chain. If it is already showing wear, a completely new kit must be installed.
Increased wear
If the chainsaw cuts crookedly in an arc, the reason may be excessive wear on the saw set. You can check by visually inspecting their contacting surfaces. To do this, you need to remove the bar from the chainsaw and look at its plane of contact with the chain from the end, placing it at eye level so that the mounting groove for the chain is completely visible.
With this inspection, you can visually assess the wear on the left and right sides of the tire in relation to the groove. As a rule, the edges should wear evenly, and if one side is worn down more, to eliminate the problem it is necessary to replace the defective one with a new one.
To ensure even tire wear, some manufacturers recommend turning it over periodically. But it is worth remembering that this recommendation is not correct for all headset models, since many manufacturers indicate on the surface of the bus the direction of movement of the chain along it, and accordingly such a part can only be installed in one position.
The figure below shows several views, the top one has the direction of installation of the chain, which is indicated by the icon on the tip of the bar and the direction of movement indicator.
Experienced technicians at chainsaw repair service centers, if increased wear is detected, advise carrying out a full diagnostic of the saw set, since if the lubrication system is working correctly and the chain is installed in the appropriate chainsaw bar, this phenomenon should not be observed, therefore, the oil supply system may have malfunctions or incorrect adjustment.
If, when working with a chainsaw, you observe a crooked cut, the first thing you should pay attention to is whether the chainsaw chain matches its bar. If everything is normal, check the sharpening of the teeth and wear of the tire; if increased wear is detected, check the functionality of the lubrication system, since the problem may lie there. And the main thing to remember is that everything in a chainsaw is interconnected and the use of low-quality oils to lubricate chains can cause premature wear and loss of the chainsaw’s performance.
Chainsaw – worthy replacement hand saws and axes. Today this tool is available in almost every household- it is indispensable when arranging personal plot, construction and repair work. Intensive use and improper care of the tool can lead to premature failure. However, it is not at all necessary for the owner of a chainsaw to immediately contact a workshop - many of the malfunctions that can happen to it during operation can be easily eliminated on their own.
Chainsaw design and general classification of faults
The main condition for successful repair is correct . Therefore, in order to determine why the chainsaw failed and, most importantly, how to make it work again, you first need to know the features of its design.
It should be noted that it is not particularly complex, as it includes:
In order to simplify the diagnosis of faults, they are usually divided into two main categories:
- engine malfunction;
- malfunctions of other chainsaw components.
Most often, failures occur in, however, other parts of the tool due to intensive use or improper care may fail at any time. How to determine exactly where the breakdown occurred? Simple logic will help us with this.
If the problem is in the engine, it will:
- won't start;
- stall;
- work unsteadily;
- overheat;
- smoke;
- develop insufficient power.
As for all other faults, as a rule they manifest themselves when the engine is running normally.
Starting the engine: checking the spark plugs
If the chainsaw does not start, the first thing to do is check the tank for . By the way, it must be prepared in the proportions specified by the engine manufacturer, otherwise the tool simply will not start. 
After making sure that the fuel mixture is correct and available, you should check the ignition system. To do this, you need to inspect the spark plug.
Her condition can say a lot:
- dry candle
indicates that the fuel mixture does not enter the carburetor, which means the problem is not in the ignition;
- fuel-spattered candle
is the result of an excess of the fuel mixture, which lies either in a violation of the engine starting algorithm or in incorrect carburetor adjustment;
- carbonated candle
this is a signal about the presence of low-quality oil in the engine lubrication system, incorrect settings carburetor or incorrectly prepared fuel mixture. 
If it is splashed with fuel, it must be thoroughly wiped after removal. The fuel supply system should also be cleaned. To do this, it is closed, after which the starter is turned on. A candle covered with soot must be carefully cleaned using an awl and sandpaper.
When checking spark plugs, you should pay attention to the distance between the electrodes (the normal gap is 0.5-0.65 mm), as well as the condition of the gasket and the presence of a spark. A damaged or worn gasket will need to be replaced, and the spark can be checked by putting on the ignition cable, connecting the cylinder and spark plug nut, and cranking the starter.
If the discharge does not occur, the spark plug needs to be replaced. If a spark does not appear even with a new spark plug, then the problem is in the connection to the high-voltage wire or in it itself.
DIY chainsaw repair: fuel supply system
If the fuel mixture does not enter the cylinder, but the spark plug works normally, this may mean that:
- The fuel filter is clogged.
To clean this unit, remove the fuel hose and check the flow. If it is weak, the filter must be removed through the filler hole of the fuel tank and cleaned or replaced if completely worn out. 
- The breather is clogged.
This is nothing more than a hole in the fuel tank cap, which is cleaned with an awl.
- The fuel mixture is not supplied or is supplied in insufficient quantities.
There may be several reasons for this:
Troubleshooting muffler problems
If it works fine at low speeds, but starts to stall and smoke at high speeds, the problem may be hidden in the muffler.
To check the quality of its work, you should do the following:
Dry cleaning without respiratory protection is not recommended. Carcinogens present in carbon deposits will be released into the surrounding atmosphere in the form of dust, the inhalation of which is extremely hazardous to health.
To prevent clogging of the muffler during operation of the chainsaw, you should carefully monitor the composition of the fuel mixture and the quality of its components.
Repair of cylinder-piston group (CPG)
If the chainsaw engine does not start or cannot develop normal power, it is likely that there is not enough pressure in the engine cylinder to burn the fuel mixture. The reason for this may be wear and tear of elements - piston, rings, bearings, etc. In order to assess the condition of this unit, it should be visually inspected after first removing the muffler. 
For a more complete diagnosis, a compression gauge is placed in the spark plug hole of a two-stroke chainsaw engine. It is used to measure compression in the engine. Based on the test results, one can judge the condition of the CPG, but accurate facts can only be obtained by completely disassembling the unit.
If the piston is chipped or scratched, it will obviously have to be replaced. The same applies to deformed or broken piston rings - for normal engine operation they must be fully functional and free of carbon deposits.
Checking the carburetor and signs that it needs to be adjusted
Correct operation guarantees maximum efficiency of the chainsaw, that is, it is possible to develop full power with the most economical consumption of the fuel mixture. Adjustment of this unit is usually carried out by the manufacturer, but its design provides for the possibility of adjustment during operation.
The fact that such adjustment will have to be made by the owner of the chainsaw is evidenced by:
- Strong vibrations or damage to the protective cap.
- CPG wear.
- Carburetor clogged.
- Inability to start the engine or its spontaneous stopping after starting.
- Increased fuel consumption and exhaust emissions with a simultaneous decrease in engine power.
The chainsaw carburetor is adjusted in strict accordance with the manufacturer’s instructions using three special screws, which are responsible for the maximum (“M”) and minimum (“L”) speeds, as well as engine idle speed (“T”). In order to eliminate unwanted interference by an inexperienced user in the operation of the carburetor, some manufacturers install only one idle screw. 
Calibration algorithm and safety precautions when troubleshooting a chainsaw carburetor
Carburetor adjustment is performed in two stages:
- Basic (carried out with the engine off).
- Finish (carried out with the engine running, preheated).
For basic adjustment, screw screws H and L until they stop and turn them back 1.5 turns. Final adjustment requires that the engine be warmed up for 5-10 minutes at low speeds.
The finishing is performed by turning out the idle screw until the minimum engine speed is reached (its operation must be stable and the chain must be motionless). If the engine stops idling, the propeller must be returned, and if saw chain is still set in motion, you should continue turning it counterclockwise.
Calibration check is performed by test:
- Acceleration (when you gently press the accelerator, the engine should quickly gain speed to its maximum).
- Maximum speed (if there are misfires, screw H should be loosened slightly).
- Idling (the chain should not move, and the engine should pick up speed as quickly as possible).
If the owner of the chainsaw is not familiar with the carburetor structure and does not have the necessary tools to calibrate it, you should contact a specialist. A carburetor is a very complex unit, so any incorrect action can lead to irreversible consequences, such as complete engine failure.
Other chainsaw malfunctions
If the diagnostics showed that everything is in order with the engine and its systems, then the cause of the malfunction should be sought elsewhere. The most common problems are:
If the cause of tool failure is not visible to the naked eye, as is the case with the engine, it is necessary to carefully diagnose the faults and eliminate them in accordance with the manufacturer’s recommendations and safety regulations.
DIY chainsaw repair, video