Chainsaw stalls at idle for reasons. Chainsaw starts and stalls reason

What to do if your chainsaw stalls? Many owners of chainsaws know the weakest points of their tool, but a situation may arise when the reason could not be immediately found.
This manual will also be useful for those who recently purchased a chainsaw.

ATTENTION! If you did not find your reason in the list below, you can ask your question in the comments.
So, the chainsaw stalled... There can be quite a few reasons, since although the saw is not a Formula 1 car, it is a technical device. Here, the main condition for successful repair will be an accurate diagnosis of the malfunction.
You should not immediately start disassembling the chainsaw; first you need to check the simplest possible causes of the malfunction. Let's look at the approximate steps to check the possible cause of the malfunction.

(This is the second edition of this article, in which I will try to describe in as much detail as possible all possible reasons.)

If your chainsaw does not start, then read more here:

Troubleshooting

If the chainsaw stalls for no apparent reason and it is not possible to establish even approximately possible problems, then it is worth going through all the possible reasons sequentially. Of course, there are typical, standard faults which we will talk about below, but for now we are going step by step!

1.Check the fuel mixture.

Firstly, it must be prepared according to the manufacturer’s recommendations and using high-quality ingredients. Secondly, exhaust the tank completely or drain the fuel mixture before long periods of inactivity or storage between seasons. Read more about fuel here:

2.Clean the air filter or change it.

A dirty air filter does not allow the supply of air in the volume for which the chainsaw is designed for normal operation. That is, if the carburetor that mixes the air and fuel mixture was adjusted with the same amount of incoming air, then when the air filter is dirty, the amount of air decreases, but the settings remain the same and as a result we get an enriched working mixture.

3.Check the spark plug.

There may also be several sub-items here. The first step is to unscrew the spark plug of the chainsaw and check whether it has flooded during startup attempts. This especially often occurs when the chainsaw is started by inexperienced users who do not follow the sequence of starting the saw when cold. In this case, you need to dry the spark plug or screw in a new one and try again according to the instructions. The spark plug tip may fail. You can check this by unscrewing the spark plug and inserting it into the tip, placing it on the block and pulling the starter cord a couple of times. If there is a spark, then the spark plug and other electrical components are in order.

Another step in checking the spark plug is to check the spark plug gap and for carbon deposits. See the manufacturer's recommendations for clearance. As a rule, this is from 0.5 to 0.65 millimeters.
Carbon deposits from the spark plug are cleaned with fine-grained sandpaper or a wire brush. Read more about candles here:

4.Check the fuel filter.

As with the air filter, the situation with the fuel filter leads to a change in the composition of the working mixture. Only if the air is contaminated does the mixture become richer, and if the fuel is contaminated, on the contrary, does it become leaner. The chainsaw engine will not operate if there is insufficient fuel in the working mixture. In addition, if the fuel filter is clogged, the uniform supply of fuel to the carburetor and further to the combustion chamber is disrupted. This is especially noticeable when the chainsaw stalls when you press the gas.

5.Check the breather.

WITH

The breather is a check valve that is located in the gas tank of a chainsaw and prevents the formation of a vacuum in the tank. If it is clogged, then no air comes in instead of the used fuel mixture and the fuel pump cannot cope with the fuel supply.

There is often a situation when fuel is pumped into the carburetor using a primer (pump for pre-priming fuel) and the chainsaw starts up. After the fuel supply in the carburetor is used up, and due to the blockage of the breather, fuel is not supplied, the chainsaw stalls.

6.Checking the carburetor

In 50% of cases, if not more, the reason that a chainsaw stalls is an incorrectly configured or failed carburetor.

What malfunctions can a carburetor conceal?

• The jets, injectors, filter, and channels are clogged. Given the “quality” of domestic fuel, the fuel filter often fails to cope with its responsibilities of cleaning gasoline from dirt, debris, and impurities. In this case, the jets become clogged and fuel is either supplied in insufficient quantities or not supplied at all. Often the chainsaw noticeably loses power. The carburetor needs to be disassembled and cleaned. Remember that the carburetor consists of small and very small parts! Therefore, before disassembling it, prepare the place in advance!
• The accelerator pump needle sticks. Often, as a result of wear or foreign objects, the accelerator pump needle may become stuck. In this case, the chainsaw may simply not start, work unstably, or stall for no apparent reason at any time.
• The check valve needle does not fit tightly to the seat. In this case, the spark plug will flood, the saw will work unstably or stall under load. It is very difficult to grind the needle to the valve seat! It is often easier to replace the carburetor...
• Worn or damaged rubber seal in the accelerator pump. If cracks appear on the cuff or it is damaged, for example during disassembly, then additional air flow (“suction”) will begin. This, in turn, will first lead to an increase in speed, and then the chainsaw will simply stall. All you need to do is replace the cuff.
• Sometimes it happens that air begins to “suck” from under the carburetor gasket. It is often very difficult to determine where exactly the “suction” is going, and in this case, you may have to change all possible seals and gaskets.

7.Checking hoses, seals, gaskets

One of the most common problems that cause a chainsaw to stall or not start is air leaks. A saw can suck in air in many different places. Check in order:

• Fuel hoses. Often, from time to time or when using low-quality materials, micro, and even non-micro, cracks can form in fuel hoses. In most cases, they can be identified by visual inspection. It is also worth inspecting the attachment points of the hoses. If the hose does not fit tightly, there may be a leak there.
• Oil seals. Even the highest quality seals can lose their tightness under the influence of time and during operation. In this case, the quality of the mixture is compromised and the saw either works unstably or starts and stalls. How to check chainsaw oil seals? There are only two of them and both are installed on the crankshaft. In order to check their tightness at home, I know of two options: 1. Check them by supplying air under pressure. This can be done using a compressor, preferably a stationary one, but you can also use a car one. It is necessary to plug all the holes, namely the outlet on the muffler side and the inlet on the carburetor side. We unscrew the spark plug and apply air under pressure. If pressure is not created or you just hear a hissing sound, then this is a clear sign that the seals need to be replaced. 2. You can check it with a special device. More details in the video:
• Gaskets can also cause air leaks. Most often they are damaged during unqualified chainsaw repairs. If you have recently assembled and disassembled your saw, then there is a very high probability that the air leak occurred precisely as a result of damage to the gasket or its incorrect installation.

Video on how to check the tightness of a chainsaw crankcase

8.Checking the muffler

As a result of long-term operation, especially if the fuel mixture is prepared with excess oil, deposits form in the muffler that prevent the free removal of exhaust gases. In this case, it is necessary to clean the muffler.

Video on how to remove a chainsaw muffler

9. Failure of the cylinder-piston group (CPG)

This is probably the most unpleasant of the breakdowns that are possible in a chainsaw. Often the cost of replacing a CPG can exceed the cost of half the entire chainsaw! This is especially true for professional models. In our case, when we consider the reasons why a chainsaw may stall, problems can be caused by scuffs on the walls of the cylinder and piston. You can check this by removing the muffler and visually inspecting the surface of the cylinder and piston. In most cases, scuffing occurs precisely on the muffler side, but sometimes the opposite situation can occur. Keep this in mind!

Video about diagnosing CPG

These are perhaps the main reasons why a chainsaw can stall. If these recommendations did not help you, describe your symptoms in the comments. We will help!

Frequently asked questions about chainsaw malfunctions and ways to solve them

The chainsaw stalls when you press the gas

One of the most common questions!!! In this case it is necessary:

• Check the fuel filter.
• Inspect the fuel hoses for leaks.
• Check the muffler.
• Try adding a little RPM.
• Look at the rubber seals on the crankshaft, the spacer between the carburetor and the cylinder.

Chainsaw stalls when hot

If the chainsaw starts well until it is warmed up, and after it has warmed up it starts to stall and does not start until it cools down, then the problem may be the following:

• Check for leaks somewhere (hoses, seals, gaskets)
• Check the muffler for carbon deposits.
• Check the CPG (cylinder-piston group) for scoring.
• Check carburetor settings
• It is also possible that the ignition coil has failed. As the saw heats up, resistance increases and the spark is either lost or becomes so weak that it is not powerful enough to ignite the mixture.

The chainsaw stalls after releasing the gas

In this case, either carburetor adjustment is required, or there is a powerful air leak somewhere.

A chainsaw has long been not a luxury, but a necessary tool for those who have a summer cottage or home ownership. But, like any other equipment, this tool tends to fail, despite its simple design.

The classification of main faults includes:

• complete lack of engine starting
• engine starts and stalls
• unstable operation of the tool
• stop work under load
• loss of power.

If the chainsaw does not start at all, the reason may be the following:

1. Manufacturing defect
2. Lack of fuel
3. Problems starting the ignition system
4. No spark from spark plugs
5. Poor fuel mixture
6. Carburetor clogged
7. Problems with high voltage wire
8. No compression.

Why does the chainsaw start and stall, what to do in this case? The reasons for this need to be examined in detail.

The reason that a chainsaw may stall immediately after the factory is due to a malfunction of a certain piece of equipment.

1. The most common reason why a chainsaw starts and stalls may be a low fuel level in the tank. This can be confirmed by the tool stopping when tilted, when fuel residues accumulate in a certain place in the fuel tank. If the fuel is of poor quality, problems with the operation of the chainsaw may also arise; in this case, you need to completely replace it.
2. A clogged breather, which significantly reduces fuel flow to the engine.
3. Insufficient contact of the wire cap with the spark plug, which leads to strong heating of the spark plug insulator. Deterioration of contact may occur due to mechanical shear or carbon deposits.
4. Broken spark plugs.
5. The muffler is clogged, due to which the exhaust gases are deteriorated, leading to the engine stopping. For this reason, the chainsaw may start and stall at idle. Sediment in the muffler can also appear due to low-quality fuel or improper use of the tool.
6. Poor carburetor adjustment.
7. Piston group failure
8. Problems with the fuel filter or pump. In this case, gasoline may leak through the pump or flow poorly through the fuel filter to the carburetor. As a result, the chainsaw starts and stalls as the speed increases.
9. Air filter dirty. Problems with this piece of equipment lead to the fact that, with increased loads on the engine, it simply cannot cope with them due to blockage and stops. A similar result is also obtained with increasing speed.
10. Short circuit due to lack of or insufficient lubrication, as well as a problem with the chain brake.

Why does a chainsaw have trouble starting and stalling?

If the equipment starts poorly “on cold”, the problem may be a lack of compression, i.e. The rings are worn out due to long service life and need to be replaced. Sometimes the reason that the engine does not start well when it is not warm is a problem with the muffler, as well as poor contact between the spark plug and the wire.

Also, reasons for poor starting may be wear or damage to the gasket or rubber cuff in the accelerator pump of the carburetor, which causes additional air flow, leading to an increase in saw speed.

Troubleshooting

The operation of the equipment must be correct, with periodic inspection of the component elements to prevent damage. To troubleshoot problems, you need to check all components of the equipment to ensure they are functioning.

If the chainsaw starts and stalls, the cause can be eliminated on your own. If it is a lack of or incorrectly prepared fuel mixture, this must be corrected. For prevention, when the chainsaw is idle, you should always drain the remaining fuel.

It is necessary to periodically check the spark plugs. In this case, you should remove carbon deposits that are clogging the connection gap, and also check the tips for the presence of fuel. Another cause of problems with spark plugs can be that they get wet with gasoline. To do this, they need to be removed, wiped with a rag and left to dry. Faulty spark plugs are replaced.

If there is no spark between the spark plug and the high-voltage wire, but there is a good connection between them, it is necessary to replace the ignition unit.

A clogged muffler is a common cause of a breakdown in which the chainsaw starts and immediately stalls. To eliminate the malfunction, you need to dismantle the muffler and clean it of carbon deposits using sandpaper or a special chemical solution. If the chainsaw model is non-separable, chemicals are poured into the system and left there for several hours, then it is purged.

The carburetor needs to be adjusted if the chainsaw stalls at idle. Fine tuning is a rather labor-intensive process, so it is usually done in service centers. But, on some models there are elements for adjusting it; just turn the bolt half a turn to increase the speed of the chainsaw, and the problems will be eliminated. If the jets, injectors, channels and filters are clogged, it is necessary to disassemble and clean the entire carburetor. When oil seals, gaskets, and cuffs wear out, they must be replaced to prevent air leaks.

If problems arise with the fuel or air filter, it is necessary to replace the fuel pump or clean the air filter.

If the breather is clogged, you need to clean it with a regular needle.

When a chainsaw starts and immediately stalls, the reason may lie in improper operation of the chain. To troubleshoot problems, check the presence of oil in the chain lubrication tank, as well as the oil drain tube for ruptures or blockages.

When inspecting the piston group, you should pay attention to the cylinder and, if necessary, replace it or the piston. You can bore the cylinder to fit the dimensions of the new piston. If the piston and cylinder are normal, you should pay attention to defects in the piston rings and the need to replace them.

Among other things, you should monitor the service life of parts indicated in the product passport, which include the drive sprocket, tire, chain, part of the anti-vibration system, and replace them in a timely manner.

If the tool is idle for a long time, it is worth checking the condition of the fuel line. If the tube is cracked, you will have to replace it with a new one.

Even with a strong desire, a chainsaw cannot be classified as a complex device. And let us also note: the simplicity of the design is its characteristic feature. However, despite this fact, even such a simple device breaks down, taking a considerable amount of time to repair.

The difficulty is not the repair procedure itself, but the correct identification of damage. Completely different deficiencies can cause the same breakdown. Therefore, there is no need to rush to immediately disassemble the engine or carburetor before signs of failure have been examined. There is little that can be useful here; you will have to use your own mind more.

Existing types of breakdowns can be classified into one of two categories: damage to the engine system with numerous groups and components in it (ignition, fuel supply, exhaust, cylinder-piston) and breakdowns of other components (lubrication system, brake, tire, clutch, etc. ).

When the engine is faulty

It often happens that the normal performance of the engine in chainsaws is disrupted. It is the search and restoration of damaged engine systems that takes up the lion's share of users' time. They may have the following manifestations:

• cannot start;
• the chainsaw stalls when it starts;
• job instability;
• It idles normally, but stalls at high rpms.

When planning to repair a chainsaw yourself, it is advisable to use the method of exceptions - consistently check the probable causes of damage. They start checking those that will take the least time to correct.

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Ignition system malfunctions

Absolutely all of the indicated types of engine malfunctions can be caused by malfunctions in the ignition system. If problems occur with your chainsaw, you should start looking for the problem with the spark plug. Which also has some other meaning: the condition of the spark plug will give a hint about the operation of the fuel group as a whole. If you find any problem, you need to analyze the spark plug, first unscrewing it. Why do you disconnect the wire and unscrew it using a special key?

A dry spark plug indicates that the source of the problem is not with the ignition system, but with a lack of fuel fluid in the cylinder. In this situation, the spark plug is screwed back in and the fuel group is analyzed.

If the spark plug is significantly contaminated with fuel, it means there is an excess of fuel. This phenomenon is associated with carburetor misalignment or non-compliance with starting requirements. In such a situation, the spark plug is cleaned and dried, the cylinder is released by closing the liquid supply and using a starter to ventilate the combustion chamber and get rid of excess liquid. Then the spark plug is returned and the start is repeated.

The presence of abundant dark carbon deposits also only confirms the presence of problems in the fuel system.

Violations may occur in the proportions between gasoline and oil, in poor carburetor adjustment, or in the addition of low quality oil. They wash the spark plug with gasoline, remove carbon deposits using a needle or awl, clean the electrodes with fine-grained sandpaper and put them back.

Also, in all situations, it makes sense to check the gap between the spark plug electrodes. According to its vintage, it must correspond to a value in the range of 0.5-0.65 mm. The sealing spark plug gasket also requires checking. If it is worn out or damaged, it will provide an insufficient seal to the combustion chamber. And this will cause a decrease in compression in the cylinder and problematic engine operation.

Even when checking the spark plug gives reason to believe that the damage is related to the fuel system, the spark plug is tested for spark formation. At least to eliminate suspicions that there are problems with this issue. Perform:

• putting a cable on the spark plug;
• using insulated pliers, press the spark plug nut or thread against the cylinder;
• press the starter handle and observe whether a spark occurs or not.

When a spark does not occur, the spark plug is changed. If even when replacing the spark plug no spark occurs, then the high-voltage condition is analyzed for breakage and contact with the spark plug.

A lack of spark can be caused by a malfunction of the ignition module or failure to maintain the gap between it and the magnetic wire of the flywheel. The latter should be equal to 0.2 mm. In particular, violation of the gap becomes quite possible if the saw was disassembled the day before and the flywheel with the ignition module was removed. The defective ignition module is replaced.

Having completed all the steps to check the ignition system and not finding any deviations, proceed to analyze the fuel supply system.

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Fuel supply system is faulty

If, when examining the spark plug, it is determined that liquid is not supplied to the cylinder, then the probable reasons for this fact are determined. They are:

• fuel is not supplied from the tank due to the cap hole (breather) being clogged, and a vacuum arises inside the tank, creating an obstacle to the exit of liquid;
• the fuel filter located in the tank is dirty;
• fuel fluid does not flow from the carburetor or does not flow in sufficient quantity into the cylinder.

In order to diagnose the first 2 reasons, remove the fuel hose from the carburetor and observe whether fuel flows out of it or not. When it flows out in a full stream, the filter and breather are not looked at. If the flow is weak or does not flow at all, then the source of damage is considered to have been found. The breather is cleaned with a needle.

Through the fill hole of the empty fuel tank, use a wire hook to remove the fuel filter along with the suction hose. From the latter, the filter is removed and cleaned or replaced with a fresh one. Chainsaw manufacturers recommend changing the fuel filter after each trimester.

A weak flow of liquid into the cylinder from the carburetor or poor proportions between liquid and air is caused by several reasons:

• clogging of the air filter;
• unadjusted carburetor, clogging of its channels or filter mesh.

Typically, the chainsaw repair procedure is accompanied by cleaning the air filter, since it becomes dirty very quickly. When this happens, the flow of air into the carburetor is reduced, and the fuel fluid at the outlet becomes too rich, which leads to interruptions in the normal functioning of the engine.

Removing a dirty filter for cleaning is done with great care so as not to shake off dirt into the carburetor. The filter is cleaned or washed with water and a cleaning agent, dried and returned to its place.

Centrifugal clutch of a chainsaw: 1 – friction linings, 2 – springs, 3 – drum.

By adjusting the carburetor, misalignment is eliminated. As usual, this is done using 3 screws - maximum and minimum rotation, idle speed. The adjustment is carried out strictly following the descriptions in the instructions. Otherwise the engine will simply break down. Other manufacturers of chainsaws provide a single idle screw in order to eliminate unnecessary interference in the performance of the carburetor by inexperienced users.

When carburetor adjustment turns out to be ineffective, clean the channels with the filter mesh and immediately check the integrity of the membrane. The carburetor of a chainsaw is considered a capricious device, so you should disassemble and clean it, understanding the full responsibility of the operation.

The peculiarity of working with it is that many small elements of its components have the ability to imperceptibly jump out of their places and get lost forever. Having disassembled such an unruly mechanism once without thinking, you may not be able to put it back together in the same form.

If you have little or no experience in carburetor repair, then it is better not to tackle it yourself, but to entrust this important undertaking to a specialist from the service center. The carburetor is sometimes cleaned there using ultrasound.

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The muffler has failed

Chainsaw fuel system: 1 – fuel filter, 2 – carburetor, 3 – manual pre-priming pump.

Often the cause of engine breakdown, especially when the engine functions perfectly at low speeds, but at high speeds it heats up and the chainsaw stalls, is clogging of the spark arrester in the muffler with combustible products, creating obstacles to full exhaust.

Repair in such a situation comes down to removing the muffler, disassembling it and wet cleaning of carbon deposits using detergents. After washing the non-removable muffler, dry it with a hairdryer. Since soot consists of carcinogenic particles, it is unacceptable to clean it dry, because toxins will enter the master’s respiratory system. After removing the muffler, the exhaust hole is plugged with a cloth.

The reason for clogging is also the reason why they use fuel fluid with an excess amount of oil (more than recommended by the manufacturer), low-quality oil or not intended for 2-stroke engines.

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Damage to the cylinder pistons group

Damage to the cylinder-piston group (CPG) is considered more serious. This includes: wear of the cylinder and piston, scratches on their walls, wear or sinking of the piston rings in the grooves, wear of the crankshaft bearings. Many of these problems cause a decrease in pressure in the cylinder and the inability of the engine to start or operate at full capacity when it heats up.

Air purification system: 1 – cover covering the fine filter, 2 – fine filter, 3 – cover covering the coarse filter, 4 – coarse filter.

The condition of the CPG is assessed in one of several ways.

1. Removing the muffler allows you to view part of the end surface of the cylinder in the opened hole. Although the visible area is small, it can still shed light on the state of the CPG.
2. Compression is measured, which is very informative regarding the condition of the CPG elements. The procedure is performed using a compression gauge placed in the spark plug hole.
3. Using a drill, a manual starter or a flexible shaft, rotate the crankshaft, immediately checking the pressure on the pressure gauge. For a saw with normal performance, it should be at least 8-9 atm (or 0.8-0.9 MPa). As it decreases, it leads to a decrease in engine performance. A pressure of 5 atm still assumes the engine is running, but at idle.

Accurate assessment of the condition of the CPG is only possible with complete disassembly of the engine: unlocking the crankcase from the cylinder and removing the piston. If nicks, chips or deep scratches are found on the latter, it is replaced. As for the cylinder, if there is damage on the surface or it is worn out, it is bored to the repair size. Low compression can be caused by wear or coking of the piston ring. A serviceable ring does not contain carbon deposits, is held freely in the piston groove, adjoining the surface of the cylinder from the inside quite tightly.

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Chain lubrication system malfunctions

Without exception, all chainsaw repair manuals contain references to damage to the chain lubrication system, which is quite common. This:

• supply of lubricant to the chain in insufficient quantity or non-supply at all;
• oil leakage.

Coarse air purification system: 1 – snow filter, 2 – mesh filter.

When the chain is dry, inspect and clean the channels supplying oil to the tire. Clogging them is not uncommon.

In case of significant (small quantities are considered normal) oil leaks, inspect the connection of the tubes to the pump fitting for leaks, which may fall off or crack. Changes in the integrity of the oil line (drips are not taken into account) can cause insufficient chain lubrication. Air is sucked into the pump, which reduces its performance. Problems with tightness can be corrected by changing the tubes or sealing them.

Cracks in the oil pump housing are considered a significant problem with the lubricant group. Then they change it.

Modernization does not stand still. And the old chainsaws, which in addition to being able to only cut wood, emitting a terrible roar and vibration that could be heard almost kilometers away, are long gone. Almost silent, thorough tools that are now a pleasure to hold in your hands have flooded the market, giving users a feeling of complete happiness and technical freedom.

But, unfortunately, no matter how technically and visually advanced the advanced technology is, its breakdowns are a fairly common occurrence, which manufacturers talk about only “by default.” Chainsaws are no exception to this, multifunctional working units that require enormous attention from the user in order to recognize the “catch” in time and stop the problem at the earliest stages.

The main of these nuances usually relate to the moment of launch, which should be taken with full responsibility. Let's look at the main processes that can occur with a chainsaw when the engine is turned on.

The chainsaw does not gain momentum - what to do?

Moreover, this phenomenon may also be accompanied by the fact that the engine periodically does not start at all, loses speed, and cannot withstand a load greater than idling. If you do not pay attention to this problem in time, you may “lose” it altogether due to severe overheating.

The main reason for this usually lies in the engine area, so that's where it's worth taking a closer look.

Other points that could lead to such consequences are:

• faults with spark plugs;
• problems with the carburetor or simply its incorrect adjustment.

The spark plug can be visually diagnosed, therefore, if it is too dry or, on the contrary, very wet, and even with a significant deposit on top, it is necessary, if not replaced with a new one, then simply cleaned or dried and tried to work outside the saw’s ignition system.

Regarding the carburetor, the source of malfunctions can be:

• wear of piston components;
• its littering;
• air filter failure;
• use of gasoline with a low octane number and inadequate quality;
• damage due to vibration effects of the tool itself.

Each individual model is usually based on a 3-screw adjustment method, and the “H” screw will help to achieve maximum torque.

And yet, if the chainsaw does not develop speed, perhaps the reason is not in itself, but in the time of year in which the work is being carried out. Thus, negative thermometer marks are one of the factors that can completely cripple a chainsaw. Many users note that in severe frosts, even pouring heated oil does not help and the lubricant involuntarily freezes on the tire. Ice coating on the carburetor and frost on it are also quite common. What can be done?

Reduce the use of the tool before the onset of damage, or if the design allows, change the damper mode from summer to winter, which is installed on some models under the air filter cover.

What can cause a chainsaw to not idle?

• clogging of filtration parts;
• disturbances in the operation of the ignition system;
• carburetor adjustments are out of order;
• the gasoline drive is defective or damaged during operation;
• the muffler or exhaust channels are clogged;
• malfunction of cylinder-piston and installed valves.

Of course, it is difficult to independently diagnose everything at once, but by moving through the suggested points you can still get an answer to your question. In half the cases, it is enough to clean the carburetor, check the installation of the jets - and the job is done, the chainsaw works as before.

What to do if the chainsaw does not slow down?

The opposite of the previous situation is when a gas-powered tool very quickly reaches high power and does not reduce it. In this case, it may occur that neither a screw on the body nor cleaning the carburetor can eliminate this. It would seem that what else is needed, the saw works, produces power as in the instructions. But the trouble is that in this case you need tens of times more fuel than usual.

The following steps may help:

• checking the throttle cable;
• inspection of the return spring, which could simply have slipped off;
• sealing the rear flap, which must be closed very tightly.

Usually one of these events can make a huge difference.

Another technical problem is the situation when the chainsaw itself picks up speed, which usually has more than one reason. In this case, as well as under load, the saw may begin to occasionally stall, preventing it from being fully used for its intended purpose.

The leading reasons for this may be:

• clogged carburetor or fuel and air filter;
• violation of the integrity of the hose that supplies fuel;
• depressurization of the leading pipe from the carburetor to the engine cylinder;
• and again, incorrect setting of one of the screws (usually the H-screw) of the carburetor system.

Therefore, the simplest thing you can do at home is to clean the carburetor and filters, both air and fuel. It is important to maintain the correct adjustment of the screw elements L and H. Some advise completely removing the fuel filter from the design, but this is not a solution, because the carburetor will not last that long.

Therefore, before starting work, you just need to look to see if it is stuck, if there are any kinks in the hoses through which the fuel flows, and then take more drastic actions.

As you can see, there are many problems, but an excellent panacea for each of them is timely diagnostics, which can answer many questions about the technical malfunction of the device even before they appear.

There are often cases when owners of chainsaws are faced with their breakdown and it does not matter at all what model of this type of equipment, since the nature of the breakdowns is almost the same for all. Well, the chainsaw has stalled, so what next? Undoubtedly, you can take the equipment to specialized services that will repair your “iron friend” for a fee. But as they say: why pay more?

After all, you can personally disassemble the instrument and repair it, since the damage may be insignificant, but in the service you will pay a lot for this. But naturally, in order to bring a tool back to life yourself, you need to be able to understand the reasons for its breakdown and how to troubleshoot it. So let's learn! In this article you can find answers to questions regarding situations when the tool simply stalls after directly pressing the gas. So let's get started.

Basic elements of chainsaws

Before we begin to delve into the issues of tool breakdowns and repairs, let’s first figure out what the chainsaw itself consists of. First of all, I would like to note that this tool belongs to the category of equipment whose operation directly depends on the internal combustion engine.

It is also important that chainsaws are equipped with a single cylinder engine, and which operates on a type of fuel such as gasoline. It is worth noting that, despite its similarity with other tools, it does not have a gearbox. And it is replaced by a kind of single-stage chain transmission, through which the chain (saw) itself moves.

In fact, a chainsaw is a fairly simple design, but this does not prevent it from being reliable, practical and capable of fully ensuring immediate uninterrupted and cyclic operation even in quite difficult conditions. This tool consists of a huge range of certain elements “vital” for its correct and productive operation. This is a carburetor, a direct chain tensioner, a tire equipped with a chain and other elements.

Characteristics and possible causes of failure. Fixing the problem yourself

Chainsaws are fairly reliable and simple designs. Therefore, if you properly care for them and handle them based on the manufacturer’s recommendations, then they fail very rarely and various types of breakdowns are quickly eliminated. But if you are faced with this situation and want to repair your instrument yourself, without resorting to the help of professionals, then delve into the information presented below.

In fact, it is impossible to clearly and accurately determine the reason why the tool does not start. or stalls when you press the gas, since there are quite a lot of factors influencing this. But do not forget that starting from the fact that the chainsaw is equipped with a simple two-stroke engine, such conditions as lubrication, fuel, spark and air are important for its effective performance.

Consequently, the carburetor directly prepares the fuel-air mixture, the filter cleans the air from dust, the ignition unit and spark plug create a spark, and the gasoline contains lubricant.

1. An important fact is that for trouble-free operation of the tool it is necessary to pay close attention to the fuel itself. Since if this kind of mixture is not prepared correctly, then most chainsaws simply will not start. Consequently, not every owner will think to look for the cause of the breakdown in the fuel. That is why, in order for your tool to always work correctly, you need to use only high-quality gasoline for the mixture.
   

   And also use only the oil that is made by the manufacturer of your tool. In addition, it is important to prepare this kind of mixture in the amount that you will definitely use in one or two weeks, but no more (see the proportion of gasoline and chainsaw oil).

   Because otherwise, overexposure of the mixture directly in the canister will lead to it losing all its octane properties and this will lead to significant problems with the instrument.

2. The cause of the breakdown may also be a direct pouring the mixture into the candle at the moment when the mechanism is started. In order to solve this problem, you need to turn out and dry the candle, but remember that it should not be heated under any circumstances. Excess fuel must be drained through the hole (spark plug), wait 20-30 minutes, then put it back in place and try to start the tool again.
3. The chainsaw stalls when you press the gas because no spark. This can happen when there is no good contact between the tip of the spark plug and the wire (high voltage). However, if this kind of connection works correctly, but there is still no spark, then the ignition unit (electronic) is the cause. It is important to note that these types of spare parts cannot be repaired, so they can only be replaced.

   

   Do not forget that by examining the spark plug you can obtain significant information regarding the breakdown of the chainsaw. Since if its surface is dry, then the reason for this is the cylinder, into which fuel is not directly supplied. That is why you will have to check the entire range of its supply step by step. If the spark plug is covered in black soot, this means that the carburetor is not working properly, that is, it supplies either a lot of fuel or pours oil directly into gasoline.

4. If the chainsaw stalls when adding gas, this means that fuel is supplied in insufficient quantities for full operation of the chainsaw. The reason for this may be either a clogged carburetor (its jet) or contamination of the filter itself (fuel). Remember that the first unit should be checked exclusively by professionals, but you can clean the second one yourself.
5. In addition, the cause of failure may be filter (air) if it is contaminated with dust. But do not forget that each model has its own easily eliminated and characteristic features. It is for this reason that do not hastily start disassembling and repairing the instrument, but it is best to “walk” through the forums, where there are a huge number of reviews from various owners, so as not to make things worse.
   

   Since, for example, a Stihl chainsaw stalls when you press the gas for a simple reason, namely a simple clogging of the direct breather.

   In order to solve this kind of problem, all you have to do is disconnect the (fuel) hose from the carburetor and pay attention to whether fuel is leaking out of it. Since if the mixture flows in a full stream, this means that the breather is not contaminated, but if on the contrary, then the cause of the breakdown has been found.

6. Here is another reason why a chainsaw stalls when you press the gas - muffler. It is this part that can interfere with the full operation of the tool in cases where it is directly contaminated with exhaust resinous deposits. To do this, you just simply need to clean it.
7. Quite often the chainsaw partner stalls when pressed and the reason for this is cylinder-piston group. Since by examining them, namely the piston and cylinder, you can easily determine the cause of the tool malfunction by directly replacing them. You can also directly bore the cylinder itself relative to the dimensions of the new piston.

   

   But if after inspection you find that there is no damage on both the piston and the cylinder, then the reason may lie directly in the rings (piston). To do this kind of check, you need to insert a piston into the cylinder and carefully begin to rock it using a connecting rod. If you suddenly feel play, then the rings need to be replaced, as they are already worn out.

8. Many people wonder: why does the chainsaw stall when I press the gas? The answer may also lie in insufficient chain lubrication(see chainsaw oil), since the oil line may be leaking, or the direct channels may simply be clogged. That is why pay attention to the chain, because if it is dry, then without delay, start cleaning the channels that supply oil directly to the tool tire. Then inspect in detail the parts where the oil pump fittings are connected to the pipes. But if you notice that oil is leaking at the joints, or you find cracks in the tubes themselves, then in the first case, seal the leaks with sealant, and the tubes will have to be replaced.

First of all, what you should remember when purchasing this kind of tool is that certain parts of the saw need to be replaced with new ones after their service life (passport) has expired. It is for this reason that the instructions should always be at your fingertips, since everything is described there in detail.

These types of details include: sprocket (drive), tire, part of the system (anti-vibration), as well as a chain. Since we should not forget that if this “filling” is not replaced with a new one at the required time, then these worn-out spare parts will negatively affect the remaining parts of the chainsaw. It is for this reason that you should check the depth of the immediate tooth cutting quite often. Remember that it should not be higher than 0.5 mm a week.

To sum it up...

Definitely, every thing we buy has its own expiration date and sooner or later it breaks, and it becomes a shame when the degree of its breakdown is so great that it cannot be repaired. But you must admit that quite often we are simply negligent in our use of technology (see about proper operation and how to properly cut down a tree so that it falls in the right direction), and when it stops working, then we try to find ways to eliminate the breakdowns, resulting in a huge number of services.

But remember that even though the equipment breaks down, we can extend its “life”. All that is necessary is to simply take care of it, break it in after replacing parts (read how chainsaws are broken in here) and keep its spare parts clean and tidy. And then, undoubtedly, it will serve for many more years. It is also important to use exclusively high-quality spare parts and “additives” (see attachments for chainsaws). Then your equipment will work smoothly, and you will simply forget what repairs are.