Chainsaw carburetor starts and stalls

chainsaw, carburetor, starts, stalls

Why does the chainsaw start and immediately stall

The chainsaw starts up and immediately stalls, the reason for this behavior may be hidden in the carburetor. A malfunctioning fuel pump or malfunctioning of the main fuel jet can cause this saw to behave like this. The inability to operate the chainsaw after starting, requires a full diagnosis at the service center.

All of the above options for engine malfunction have similar causes, which, depending on their neglect, can have different manifestations. For example, with a slight intake of air into the crankcase of the engine, its work will not change much, the engine power will drop slightly, its maximum speed will increase, and it will be able to heat up a little more. In the middle stages of air leakage, the engine will stop idling and will get very hot during operation. Strong air suction, will make it impossible for the saw to work, it will start and immediately stall.

In parallel with the visible manifestations of malfunctions, for example, the inoperability of the chainsaw after starting, processes will take place inside the engine at the time of its malfunctioning, which irreversibly lead the saw to the most serious consequences, for example, melting the piston, jamming the crankshaft.

The chainsaw starts and stalls cause

Owners of chainsaws sometimes have to deal with the fact that the saw, for no apparent reason, stops working normally. To understand why the chainsaw stalls under various operating modes, and also to describe how you can diagnose a malfunction, we will try in our article.

  • Why does a chainsaw stall when heated
  • Why does a chainsaw stall under load
  • Why the chainsaw doesn’t pick up speed and stalls
  • Algorithm for checking the crankcase for leaks
  • Why does the chainsaw start and immediately stall
  • Malfunctions leading to improper operation of the chainsaw
  • Summing up

Malfunctions leading to improper operation of the chainsaw

There are a number of faults that must be taken into account when diagnosing, since they can lead to interruptions in the operation of the saw.

  • Worn crankshaft bearings. With worn out crankshaft bearings, runout is inevitable on the main shaft, where the flywheel is attached. In such a situation, it is impossible to adjust the gap between the flywheel and the ignition coil, which entails interruptions in sparking, and the unstable operation of the chainsaw.
  • Impulse channel contamination. The impulse channel serves to ensure the operation of the fuel pump, respectively, its contamination leads to improper operation of the pump, which will make it impossible for the saw to work (it will start and immediately stall).
  • CPG wear. As a rule, with increased wear of the CPG, there is a decrease in compression in the engine of the chainsaw, which will necessarily affect its ability to develop speed.
  • Dirty fuel and air filters.

Algorithm for checking the crankcase for leaks

  • Remove the side cover and tire from the chainsaw.
  • Unscrew the spark plug and put a lace with knots into the cylinder through the spark plug hole, thereby stopping the movement of the piston and crankshaft.
  • As a lace with knots, you can use the old cord from the starter, tying knots on it every 3-5 cm.
  • Spin the chain saw drive sprocket.
  • Remove the oil pump cover and the pump itself.
  • Remove the starter from the chainsaw.
  • Unscrew and remove the flywheel.
  • Remove carburetor.
  • Using a syringe, through the carburetor hole in the cylinder, pour gasoline into the crankcase, while observing the crankshaft oil seals. If gasoline flows through them, then the oil seals have become unusable and must be replaced with new ones.
  • It is better to entrust the installation of oil seals to professionals.

An indirect sign of crankcase leaks are oil leaks in the area of ​​the oil seals.

Why does a chainsaw stall when heated

The situation in which a chainsaw starts up cold, and in the process of heating it can stall, is familiar to many who deal with them. The main reasons for this behavior of the saw are as follows.

  • Defective ignition module (coil). Determine the malfunction by checking the spark first on a cold engine, and then on a hot one. If there is no spark on a hot engine, then it is worth trying to fix the malfunction by replacing the ignition coil.
  • The carburetor of the chainsaw has an incorrect setting (fills a hot candle). You can determine the problem by how the saw is started on a cold one. If for a cold start it is not required to close the air damper, and the engine starts without a preliminary flash, then the fuel mixture is formed incorrectly and after the engine warms up, the fuel fills the spark plug and makes it impossible to start. The problem is eliminated by adjusting the carburetor.
  • Spark plug defective. In such a situation, similar to a faulty ignition coil, the spark disappears when the engine heats up. It is worth trying to replace the spark plug with a new one, and if this does not help, then you need to check the ignition coil and the gap between it and the flywheel.

You can check the ignition coil using a multimeter or by replacing it with a known good one. The test with a multimeter of the primary and secondary windings is carried out in the resistance measurement mode. The resistance index of the primary winding, working coil, is 1 kOhm. secondary 4 kOhm.

Why the chainsaw doesn’t pick up speed and stalls

If the chainsaw is not able to pick up speed a minute after starting or stalls when the gas trigger is pressed, most likely the carburetor or crankcase is leaking. As in the previous case, the problem can be solved by checking for leaks and adjusting the carburetor.

If the chainsaw does not pick up speed and stalls after it has been running normally for about 5 minutes, the reason may be a defective fuel tank breather. The vacuum created in the fuel tank during tool operation prevents the engine from receiving the necessary amount of fuel for its normal operation, and for this reason it will be unable to gain speed or stall. At the same time, if you stop the tool, open and close the fuel tank cap and start the chainsaw again, the tool will work normally again for about five minutes, after which it will stop gaining speed or stall.

The reason that the chainsaw does not pick up speed can also be excessive carbon deposits in the muffler, which makes it difficult to exhaust exhaust gases, thereby reducing the power and engine speed.

If you want to check the tightness of the crankcase, but there is no special tool, you can use the following test procedure.

Why does a chainsaw stall under load

In some cases, the chainsaw under load is unable to work normally and simply stalls. A common reason for this behavior is improper carburetor adjustment, or air leaks through the crankshaft oil seals or carburetor gasket. And also this behavior can occur due to leaks in the carburetor.

It is best to diagnose the cause and eliminate the fact that the chainsaw starts and stalls under load, best of all in a service center, since a special tool is needed to check the tightness of the carburetor and crankcase.

A saw that is unable to operate under load will also be unsteady at idle speed. They will “float”. Diagnostics begin with a check for leaks in the crankcase and carburetor. If air leaks through the crankshaft oil seals, they must be replaced. If air leakage is detected in the carburetor, the cause can be eliminated by installing a repair kit of gaskets.

Only after the above actions have not yielded results and the crankcase with the carburetor is sealed, you can start adjusting the carburetor.

The reason for this algorithm is as follows, if the air leak from the crankcase is not eliminated, but the carburetor was simply adjusted to normal engine operation, then the fuel mixture will contain more fuel than is required with a sealed crankcase, which in turn will significantly increase its consumption. Also, most likely, carbon deposits will appear in the engine, which will also negatively affect the further operation of the chainsaw.

Husqvarna chainsaw won’t stay running

In some models of chainsaws, to ensure the operation of the fuel pump, special hoses are installed that transmit an air impulse from the engine crankcase to the carburetor fuel pump. If this hose is frayed, the saw will idle unevenly and will not work at all under load.

Owners of Husqvarna 137 and Husqvarna 142 household chainsaws should first of all check the impulse hose for any deviations in engine operation from the norm, since this is considered the most common reason for the breakdown of these chainsaws.

A video showing how to replace a defective impulse hose with your own hands on a Husqvarna 142 chainsaw can be viewed below. It shows step by step the process of disassembling the saw, shows the impulse hose and stipulates the consequences of its malfunction Husqvarna 142.

Summing up

When the first signs of improper operation of the chainsaw appear, it is worthwhile to carry out a complete diagnosis. In order to avoid damage to the saw as a result of improper maintenance, it is better to entrust the work of identifying and eliminating engine malfunctions to professionals. And most importantly, you do not need to use a chainsaw with minor defects, since this will lead to even greater problems.

Read more:  Stihl Chainsaw Doesn't Develop Turnovers

Chainsaw stalls under load

If the chainsaw stalls under load, this may be due to the fuel system or a dirty air filter. Changing the fuel with the correct gasoline / oil ratio or cleaning the air filter are universal solutions to this problem. An improperly prepared mixture of low-quality gasoline and, for example, engine oil is the main reason for the malfunctioning of a chainsaw, including in the case when it heats up and stalls.

The chainsaw stalls immediately

What to do if the chainsaw stalls immediately after starting? First you need to check the presence of fuel in the gas tank. If its level is not enough, then you need to prepare the fuel mixture in strict accordance with the ratio of gasoline and oil prescribed in the operating instructions. Gasoline must have the highest possible octane number, and the required brand of oil, as a rule, is indicated in the data sheet of the chainsaw.

Next, we check the spark plug, as well as the contact of its tip with the high-voltage wire. The gap between them should be no more than 0.5 mm. If necessary, the candle is cleaned of carbon deposits and dried. It is recommended to occasionally change the candle to a completely new one. The reasons for the tool stalling when you press the gas lie in the fuel filter or carburetor jet. Cleaning the gas filter will not take much time and effort, but it is better to entrust the disassembly and cleaning of the carburetor to the specialists of the service center.

Chainsaw stalls at idle speed

Cases are common when the chainsaw stalls at idle. First of all, you need to check the muffler, and, if it is dirty, clean it from exhaust tar deposits. Also on the carburetors of some models, etc., there are bolts with the inscriptions H and L. respectively, rough and fine tuning. By adjusting the bolt L during the operation of the chainsaw in such a way that its speed increases (turn the bolt just half a turn), it is possible to eliminate this problem. Adjusting the carburetor requires the mandatory presence of an electronic tachometer and is a rather time-consuming process. That is why in such cases it is better to turn to professionals.

The chainsaw starts and stalls. Why?

There are several simple rules for the operation and maintenance of a chainsaw, the observance of which will maximize its service life. Preparing the correct fuel mixture, regularly cleaning filters and periodically replacing parts will save you from having to repair your tool for a long time. If it was not possible to avoid the breakdown, then you can figure out its cause completely independently. This applies to any brands of chainsaws, from the more complex Husqvarna and Stihl models to the simplest Makita and Patriot models.

Chainsaw stalls when tilted

With the horizontal position of the chainsaw, the fuel pipe lies at the bottom of the gas tank, but when the tool is tilted, the pipe is above the fuel mixture, i.e. in the air. This is precisely the reason that the chainsaw stalls on its side.

Chainsaw stalls at high revs

In the event that the tool stalls at high rpm, there are three parts to check: the air filter, the fuel pump, and the gasoline filter. The air filter must be cleaned, you can even wash it under water and dry it thoroughly. Then it is enough to disconnect the fuel hose from the carburetor and see if fuel flows out of it or not. If it flows with a full stream, the petrol filter need not be checked. If, on the contrary, the fault has been found. The breather can be cleaned with a regular needle, and the filter can be carefully disconnected from the suction hose, cleaned or replaced with a new one. The gasoline pump is checked for wear: if fuel does not seep through it, then everything is fine with it. If the problem that your tool stalls at full speed is due to some damage to the pump, then this part just needs to be replaced with a new one.

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Why the chainsaw starts and stalls

If the saw does start, but stalls at the first attempts to do the job, the reason may be different. The reason is chain jam due to lack of lubrication or problems with the chain brake, which makes further work impossible. In this case, check the oil level in the container. If everything is in order, the reason may lie in the tube leading the fluid to the lubrication mechanism. It can clog, break, stopping oil flow, or burst, causing oil to leak out without reaching its destination.
The reason is problems with the carburetor. Parts of it may have deteriorated and require cleaning or adjustment. It is quite difficult to determine the breakdown in this case. Cleaning the carburetor is a rather difficult and monotonous task that not everyone can do. The same applies to checking the condition of its parts. It is better to entrust such an operation to professionals. The only thing you can do at home (but only for some models) is to customize it. All instructions on how to do this are in the accompanying documentation.

Chainsaw carburetor

The last reason is trivial. the low level of the fuel mixture in the tank. It manifests itself when the chainsaw stalls when tilted. The mystery lies in the fact that when the fuel runs out when tilted, it accumulates in a certain part of the tank. When tilted, the suction tube may end up in the airy part, which stops fuel flow into the chamber.

Chainsaw outlet check.

One of the reasons that a chainsaw does not start well may be a clogged exhaust channel or its muffler. At the same time, a drop in power is noted in the process of sawing sawn timber and logs. This is most often due to resinous deposits on the spark arrestor or muffler channel, which are formed during the combustion of a poor-quality mixture of gasoline and oil, which impede the removal of exhaust gases.

Resonator clogged with carbon deposits can cause poor starting of the gasoline saw.

Eliminate the reason for the poor start of the chainsaw, in this case, you can remove the accumulated combustion products. To do this, perform a number of manipulations:

  • Remove the muffler by unscrewing the screws;
  • Remove the cooling panel and gasket;
  • Remove the spark arrestor;
  • Disassemble the resonator housing;
  • Wash all elements from carbon deposits with a detergent;
  • Let them dry completely;
  • Collect everything in reverse order;

To prevent dust and sand from entering the cylinder when cleaning the muffler, cover the outlet of the chainsaw engine with a clean rag.

Checking the breather and cleaning it.

The breather is another element, from the improper operation of which the chainsaw may not start or stall during the sawing process. This element is located on the fuel tank cap in the area of ​​the air hole. This is a kind of valve that does not allow gasoline to flow out and equalizes the air pressure required for the free flow of fuel into the carburetor.

If the breather is dirty, the working chainsaw stalls, and when started, it refuses to start. The thing is that air stops flowing through the hole. As a result, a negative pressure (vacuum) is created inside the fuel tank, preventing the flow of gasoline to the carburetor.

Defining the problem is pretty straightforward. Disconnect the fuel hose from the carburetor and see what happens to the gasoline. If it flows freely in a good trickle, then everything is in order with the breather. If it is absent or it flows weakly and intermittently, then the reason is identified. the breather is clogged with dirt. You can solve the problem by cleaning the air hole with a regular needle or a powerful jet of compressed air.

chainsaw, carburetor, starts, stalls

Stihl chainsaw won’t start

The lightweight, convenient and compact Stihl chainsaw is often purchased for household work. Sometimes the owners are upset that the tool does not start: the engine turns on and suddenly stalls. In this article we will consider several reasons for such a malfunction, when the Stihl chainsaw does not start well or does not start at all.

The first thing that needs to be done in this case is to check the condition of the filter, the functionality of the fuel pump and carburetor, the external condition of the spark plug. perhaps there is no spark on the chainsaw. The same preventive work can include an assessment of the performance of pistons, cylinders, mufflers, crankshaft bearings.

After preliminary diagnostics, you need to try again to start the chainsaw, and contact a specialist if the problem is not resolved. One of the factors in the malfunction of the Stihl chainsaw may be insufficient lubrication of units and structural parts that rub during operation.

Checking the fuel mixture and spark plugs

The fuel mixture that is poured into the chainsaw must be pre-prepared. First of all, we must not forget that in the manufacture of the fuel mixture, it is necessary to use only high-quality components that are approved according to the operating book. Also, we must not forget that it is best to drain fuel before storing equipment or between seasons when the chainsaw is idle.

Read more:  Dismantling the Stihl 180 Chainsaw

Spark plug testing can be divided into several sections. First, you need to remove the spark plugs and check their tips for fuel. This can happen from time to time when the chainsaw starts. Most often this happens to inexperienced users who simply forget to follow the sequence rules when the chainsaw starts at cold speeds.

Secondly, there may be carbon deposits on the spark plugs, which simply clogs the joint gap. The gap should have a distance of 0.5 to 0.65 mm. Remove carbon deposits with fine-grain emery paper or a metal-hair brush.

Checking the spark on the spark plug and eliminating the causes.

The first step in finding the reasons why the gasoline saw won’t start is to check the spark on the spark plug. There are many factors that affect the performance of this element. However, the main ones at the initial stage of instrument troubleshooting are:

  • Incorrect carburetor adjustment;
  • The presence of more than it should be, the amount of oil in gasoline;
  • Clogged air filter.

All of them contribute to the formation of carbon deposits on the spark plug electrodes. In 50 cases out of 100, the saws do not start on a cold one due to the absence of a spark due to carbon deposits on the electrodes and their corrosion. As a result, the gap either decreases or increases.

Checking the spark plug with an idle chainsaw

It is quite easy to check for a spark. This will require:

  • Remove the tip of the high-voltage wire;
  • Unscrew the candle;
  • Put the tip back on;
  • Lean the candle with a skirt against the cylinder;
  • Start with a starter.

If a good spark is observed between the electrodes at the time of starting the engine of the chainsaw, then everything is in order with the ignition unit. If it is not there, then it is worth cleaning the element itself and checking the gap of the electrodes. If necessary, use a special probe to adjust the distance between the contacts.

For candles from different manufacturers, the distance between the electrodes may fluctuate. For some, it may be equal to 0.5 mm. Others have 0.2 mm. Therefore, carefully study the manufacturer’s recommendations.

There may be no spark on the spark plug for other reasons. Of the main faults affecting the poor start of the chainsaw and the unstable operation of the internal combustion engine at idle, from which the tool can stall, the following can be attributed:

  • Overflow of the spark plug channel with fuel;
  • Lack of contact between the high-voltage cradle and the tip of the candle;
  • Failure of the ignition unit.

How to start a cold chainsaw if the spark plug channel is constantly flooding with gasoline? To eliminate the problem while starting the tool, you can use the following algorithm:

  • Unscrew the candle with a special key;
  • Wipe it with a clean and dry cloth;
  • Dry for 20. 30 minutes;
  • Remove carbon deposits with a file and adjust the gap between the electrodes;
  • Drain the remaining fuel from the spark plug channel and dry it;
  • Collect everything and try to start the mechanism.

As a rule, these measures are enough to start the chainsaw and get the job done. However, this extreme measure does not eliminate the main reason why the engine does not start or stalls. improper operation of the carburetor, which needs fine adjustment.

If there is no spark and poor contact of the high-voltage cradle with the spark plug tip, check the connection. The check can be done using a conventional tester. If a defect is found and it is eliminated, the chainsaw should start without any problems.

If the check showed that the contact is reliable, and the saw does not start further, look for the cause in the ignition unit. As a rule, a faulty unit cannot be repaired and restored. A complete replacement is required here.

The main causes of chainsaw breakdown

Although all possible breakdowns in some specific parts of the chainsaw system have been described, their solution may not be enough. It is necessary to dwell on some aspects of problem solving in more detail.

Where to look for the reason or where to start checking

All chainsaws have the same design and work according to the same principle. The chainsaw device can be found in this material. It does not matter which brand of tool. Stihl, Husqvarna, ECHO, Champion, Partner, Shturm and others. A malfunction that manifests itself in the form when the chainsaw stalls when you press the gas can occur equally both on expensive and high-quality tools and on budget Chinese devices. If a problem occurs, then it needs to be solved.

A chainsaw is a system of mechanisms consisting of parts. Any part in the mechanism can fail, which will lead to partial or complete failure of the tool. If the engine of the tool starts, this does not mean that the chainsaw is completely operational. When the engine stops working when the engine speed rises, there are corresponding reasons for this. With this malfunction, attention should be paid initially to a number of the following tool mechanisms:

  • Gas tank. make sure there is fuel. If there is sufficient fuel, you should also check the serviceability of the fuel filter, the presence of the connection of the supply hose with the carburetor, and also make sure that the breather is working

These are the main parts and mechanisms that should be checked first of all if a malfunction occurs when the chainsaw stalls when the accelerator is pressed. There are other reasons why a chainsaw engine stalls when the gas trigger is pulled. What else can contribute to the occurrence of this malfunction, as well as the features of eliminating breakdowns, we will find out further.

When you press the gas, the chainsaw starts to stall. reasons and solutions to the problem

The chainsaw is a highly efficient tool for working with wood. However, the high-speed motor of this tool can be used for a variety of other tasks, which is achieved through special attachments. Sometimes a malfunction such as the chainsaw stalls when you press the gas, which can be triggered by some factors. In order not to have to disassemble the tool completely, we will consider all sorts of reasons for this problem with a detailed description of how to fix them.

chainsaw, carburetor, starts, stalls

Adjusting the carburetor when the engine stalls when accelerating

If the check showed that the fuel supply system, muffler and spark plug are in good working order, then you need to look for a breakdown in other places. Initially, do not rush to disassemble the cylinder-piston group or change the carburetor. It is recommended to start repairs by adjusting the carburetor. For this, all chainsaws have special adjusting screws. They are designed to adjust the idle speed, as well as adjust the fuel supply at low and high speeds. A detailed description of how to adjust the carburetor of a chainsaw is described on the website.

Today we will consider the features of setting the carburetor at maximum speed. You can make sure that the chainsaw is not developing full power using a tachometer. If there is no device, then you can make sure that the engine does not develop maximum speed by ear. We are interested in the screw on the carburetor. Which is for setting high rpm. It is usually denoted by the Latin letter “H”, which is abbreviated from the word “High” (high or large).

To adjust the high speed of the chainsaw, you will need to perform the following manipulations:

  • Tighten screw H clockwise until it stops.
  • Next, you need to loosen it by 1.25-1.5 turns
  • Run the tool and test the speed performance

It is recommended to adjust the tachometer, but if it is not there, then you can check the maximum speed when the tool is working under load.

After a banal carburetor setting, you can fix the problem with the termination of the engine when the speed rises. It should be noted that it is necessary to adjust the carburetor of the chainsaw regularly, depending on the frequency of operation of the tool. It is not difficult to do this on your own, but you can achieve accurate tuning in one case. if you use a tachometer.

Why else can a chainsaw stall when you press the gas

If, after adjusting the carburetor of the chainsaw, the problem remains, then you should resort to checking a number of other factors. There are enough of such factors, and their verification must be carried out sequentially, moving from the easier to the more complex. It is in this order that we will consider all the reasons why the chainsaw does not develop high revs, and at the same time stalls. It should be noted that in this case, the tool starts up and works properly at idle speed.

  • Check the chain tension. if the cutting element is tightened too much, this will put a heavy load on the engine. In this case, it will be difficult for a high-speed engine to turn the chain, as a result of which we get its termination of work. The problem can be corrected if the chain tension is correctly adjusted. The chain should rotate easily by hand, but keep in mind that at XX it should not move. If the chain moves at idle speed, then you need to adjust the upper screw XX
  • The quality of the fuel mixture and the correctness of its preparation. It is recommended to use AI-92 gasoline for the chainsaw. It is mixed with two-stroke oil in appropriate proportions. Although the mixing ratio is indicated on the label of the container with oil, it is necessary to use the data indicated by the tool manufacturer. The optimal value of the mixture of gasoline and oil is 40/1, that is, 25 ml of oil must be added to 1 liter of gasoline. The proportion means that for 40 liters of gasoline you need to add 1 liter of oil. If you do not adhere to the manufacturer’s recommendations, then in the end this negatively affects the operation of the carburetor and the serviceability of the CPG
  • Silencer. very often sawfillers do not pay enough attention to the exhaust system of the tool. If the muffler is clogged, and this necessarily happens over time, this negatively affects the operation of the motor. Silencers on chainsaws are collapsible and non-collapsible. For non-separable devices, the connections are flared, so in case of clogging, you need to either replace the part, or flare for cleaning. A clogged muffler affects the operation of the tool, so do not wait until the chainsaw stops starting
  • Air leaks. parts and mechanisms of the chainsaw are connected to the cylinder through gaskets. As a result, such connections are sealed, which is important for the operation of the internal combustion engine. Tightening the bolts and nuts that secure the carburetor and muffler will help to verify such a malfunction. Suction can also occur due to deterioration of the gaskets, which should be replaced on the tool.
  • Fuel and air filters are elements responsible for filtering the air and the fuel mixture. If the air filter is clogged, increasing the throttle opening will not allow enough air to flow into the carburetor, causing the spark plug to flood. As a result, the engine will stall when trying to develop maximum speed. If the fuel filter is defective, the required amount of fuel does not enter the carburetor. Its lack leads to the fact that the tool cannot develop momentum, and immediately starts to stall
  • The presence of a fuel filter. This element can not only become clogged, but also detach from the fuel hose. As a result, it turns out that dirt will enter the carburetor, which will very quickly disable the mechanism.
  • A breather is a hole through which air enters the chainsaw tank, thereby eliminating the creation of a vacuum inside a sealed container. The breather is located on the lid of the gas tank or can be built into the wall of the tank. The principle of its operation is such that as the gasoline in the tank is consumed, the tank is filled with air. If the breather is defective, a vacuum is created in the tank, which prevents fuel from being pumped into the carburetor. The breather allows air to pass in one direction, and eliminates the possibility of fuel leakage from the tank. You can repair the part using a thin needle, which punches a hole
  • CPG malfunction. the chainsaw does not pick up speed also if the cylinder-piston group is worn out. To identify this cause, it is not at all necessary to disassemble the engine to look inside. A compressor should be used to check the amount of compression. The normal value should be at least 12 atmospheres, and if the value is lower, then the CPG must be replaced
  • Ignition System. If the engine starts, it is unlikely that the problem is an electrical malfunction. However, it will not be superfluous to unscrew the spark plug and visually inspect it. The presence of black carbon indicates the need to check the ignition. The first step is to check the gap between the ignition module and the flywheel, the value of which should be 0.25 mm. The integrity of the armored wire is also checked, and if it is damaged, then it must be replaced along with the module. Spark plugs have an appropriate resource, so they need to be changed, pre-setting a gap of 0.5-0.7 mm (indicated in the technical description for each tool model)
Read more:  How to check a piston on a chainsaw

If checking all the reasons does not allow a positive result to be achieved, then the carburetor of the chainsaw should be removed and cleaned.

The chainsaw stalls at high speeds. simple carburetor repair

The carburetor of the instrument is exactly the mechanism that most owners are afraid to disassemble on their own. The reason is that this mechanism consists of many small parts, the location of which must be remembered when carrying out dismantling work. However, not everything is as scary and difficult as it might seem. To understand how the carburetor has to do with the problem of stopping the engine when the engine speed increases, you need to find out its principle of operation, described on the website.

The chainsaw stalls when you press the gas due to the carburetor, if:

  • Diaphragm damaged
  • Clogged filter element (mesh in the carburetor). This malfunction can be encountered by owners of tools who do not have a fuel filter or it is simply disconnected from the fuel hose.
  • Needle sticking, which may be due to outdated fuel mixture
  • Clogged nozzles or clogged carburetor
  • Bending of the connecting part connecting the membrane with the needle to supply fuel to the fuel chamber of the carburetor. This part is also called a foot, since under the influence of the membrane on it, the needle moves and the channel opens. During operation, this foot can bend (work out) or break (the engine will not start if it breaks). If the foot is bent, then it can be unbent, but this does not guarantee that the problem will soon recur, therefore it is recommended to replace the part

It is recommended to clean and wash the chainsaw carburetor, as well as replace defective parts and elements. After that, you can put it back, not forgetting to also replace (if worn out) the gasket between the carburetor and the adapter.

Why the chainsaw stalls when the accelerator is pressed. summing up

When making an upgrade for the reasons why the saw stalls after you press the gas, you need to take stock of all sorts of reasons and their elimination. The reasons can be conditionally divided into two parts. simple and complex. You need to start troubleshooting with simple reasons, and end with more complex ones.

You definitely need to start the check from the tank, not from the carburetor, but from the gas tank. And make sure you are using a properly prepared mixture. Next, you need to check the serviceability of the muffler and the presence of carbon deposits on the spark plug. After that, you will already have an idea of ​​in which part of the tool you need to look for a breakdown. Perhaps a breakdown is. That you just need to wind up the maximum speed, for which the carburetor is tuned. If this does not solve the problem, then you should check the air filter and clean it.

Pay special attention to the carburetor, after cleaning and possibly repairing which the chainsaw should work like new. If even after this the problem remains, then do not be too lazy to check the amount of compression. Perhaps the engine has a strong performance, and needs to be replaced.

This completes the upgrade to restore the tool’s performance, and it is worth noting one more point, such as the use of fuel that has been stored for a long time. Many people dilute gasoline with oil, and store the mixture for months, and sometimes for six months. This cannot be done in any way, since the mixture has the properties of aging, and therefore, after its preparation, it must be used within 1-2 weeks. If you do not follow this recommendation, then you will often need to change not only the fuel filters, but also clean the carburetor, but the worst thing is that this contributes to accelerated wear of the CPG.