Chinese Chainsaw Won’T Start

Doesn’t start on cold and hot main reasons

If there is a spark on the chainsaw, but the tool does not start cold, then the reason lies directly in the absence of compression. Measure the amount of compression of the engine to verify this problem. If the compression value is NOT lower than 8 atmospheres, then everything is in order. If not, then the engine has worked its way out, and the CPG needs to be replaced. When the metal parts are cold, they narrow, thereby reducing the compression. To start the chainsaw on a cold one with low engine compression, you should do the following:

  • Pull the starter handle until the internal parts do NOT warm up due to friction
  • When parts are warmed up, compression will increase, so the engine will start
  • It is recommended to carry out these manipulations in the warm season, since it is almost impossible to start a chainsaw in winter with low compression.

It should be noted that it is very harmful to work with a tool with low compression. In addition to low performance, such operation will lead to permanent damage to the chainsaw engine.

Another situation when the chainsaw will not start hot. This is primarily due to engine flooding. If it starts well on a cold chainsaw, but when there is a break after work, and there are difficulties with starting, then it is necessary to start without closing the air damper. The damper must be fully open (air is supplied) to start the engine hot. If you can’t start the chainsaw, then you need to half-close the choke. Try to start the engine, and as soon as it starts, you can open the throttle completely.

If you cannot start a heated chainsaw engine, then proceed as follows:

  • Loosen the idle screw in a clockwise direction by орота a turn.
  • Increase the number of revolutions, simplifies the process of starting the engine
  • Start the engine with the choke half open
  • After starting the engine, return the idle screw to the opposite position if the chain moves at idle

Filling the spark plug can be due to a malfunction of the ignition module, as well as a large gap between the coil and the magneto. If the reason for the impossibility of starting the engine of the chainsaw in the carburetor, then it should be correctly adjusted as soon as possible.

Is there fuel in the tank and what is its quality

Checking the presence of fuel in the tank. This is the first place to start diagnostics. Even if there is still fuel in the tank visually, make sure that the fuel line is lowered into it. If the fuel in the tank is at the bottom, then this is the main prerequisite for the fact that it is impossible to start the engine. After adding fuel to the tank, it is necessary to pump the system, and only then carry out a test run of the engine.

If there is enough fuel in the tank, make sure that the supply hose inside the tank is NOT disconnected. On some models of chainsaws, such a malfunction is a “disease”. If the tank is full, this does NOT mean that the breakdown is not related to the fuel system. Check the quality of the fuel (oil and gasoline). Gasoline for chainsaws is used mainly of the AI-92 brand. Only a special two-stroke oil should be used as oil, but NOT motor oil or at all working off.

The prepared fuel mixture cannot be stored for more than 2 weeks, as the mixture begins to lose its properties, which negatively affects not only the operation of the engine, but also its starting. How does a poor-quality mixture affect engine starting, you ask? Everything is very simple, with long-term storage of the mixture, oil precipitates, which leads to clogging of the channels and jets of the carburetor.

The instructions for each brand of chainsaw indicate recommendations in what ratio should be diluted with gasoline and oil. It is this recommendation that should be followed when preparing a mixture for a two-stroke engine of a chainsaw, otherwise it will significantly reduce the life of your tool.

The main reasons why the chainsaw won’t start

When the chainsaw does not start, the search for the cause should begin with diagnostic procedures. To carry out them, it is not at all necessary to understand the device of the gasoline tool, and it is enough to follow the sequence of actions. Common reasons why your chainsaw won’t start are:

  • Fuel line malfunction. From the tank, fuel in the form of gasoline with oil flows through the fuel line to the carburetor. The carburetor membrane, which acts as a pump, is responsible for its transportation. If there is no fuel in the tank, then naturally the chainsaw will start, so the first step is to make sure that there is fuel in the gas tank
  • Ignition system. Most often, the spark plug is to blame for the fact that the engine of the chainsaw does not start. This is due to the fact that it has a certain resource, and if the tool is used often and for a long time, then the candle fails. After making sure that there is fuel in the tank, you need to check the condition of the spark plug
  • Filtering elements. These are fuel and air cleaners that prevent small grains of sand from entering the carburetor and cylinder. The fuel filter cleans the fuel, and it is located on the fuel supply line to the gas tank. The air cleaner is located in the carburetor, and limits the ingress of chips and sawdust into the carburetor
  • Breather or pressure equalizer. This is the smallest element, which is often the main precondition that the chainsaw will NOT start. The main symptom of a malfunction is Breather. When the engine stalls during operation
  • Muffler or exhaust port. During the operation of the tool, carbon deposits settle on the walls of the exhaust system. As a result, the exhaust gases have nowhere to go, and therefore the chainsaw does not start, and if it starts, it immediately stalls
  • Carburetor. This is already a more serious malfunction, which can be eliminated by cleaning the device responsible for mixing fuel with air and supplying the finished mixture to the cylinder. Plugged carburetor passages and nozzles will cause the engine to not start
  • CPG. This is the most extreme reason why the chainsaw won’t start. The compression gauge will help to make sure of the wear of the cylinder-piston group. Having measured the compression of the chainsaw, you can make the Corresponding conclusion about the health of the engine itself
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These are all the components that need to be checked in order to find and eliminate the cause of the inability to start the chainsaw engine. In more detail each type of malfunction, as well as ways to eliminate them, we will consider further.

If the chainsaw won’t start anyway what to do

The above are the main reasons why the chainsaw does not start. And this applies to tools of different brands Stihl, Husqvarna, Partner, Makita, Champion and others. In the Friendship chainsaws, the principle of operation is different, but in general, the troubleshooting should begin with the ignition system, or rather. Inspection of the condition of the electrodes of the candle. If the performed manipulations DO NOT help to Get the desired result, then it is necessary to resort to more serious actions. This means that you need to follow these steps:

  • Check the serviceability of the carburetor and adjust it
  • Measure the amount of compression of the engine, and then make the Corresponding conclusion in its serviceability
  • Compression in the crankcase is checked

Checking the compression in the cylinder allows you to assess the condition and serviceability of the CPG. To measure compression, you need a compression meter. It is screwed into the spark plug hole, after which the starter handle is pulled. The compressor shows the corresponding cylinder pressure. This value should be at the level of 8-12 atmospheres.

If the pressure is significantly lower, then this is a direct sign of a device malfunction. In case of malfunction, the cylinder-piston group is replaced with a new one. When installing a new CPG, it is necessary to carefully treat all parts with oil so that at the time of starting the engine, chips and scuffs are NOT formed.

If there is no compression in the crankcase, then the chainsaw will also not start. The reason for the decrease in the pressure in the crankcase is the gasket, or rather its damage. This gasket is placed between the cylinder and the crankcase, and to make sure it is working properly, you should perform the following manipulations:

  • Disconnect the fuel line from the tank
  • Lower the tube into a container with a prepared mixture of gasoline and oil
  • Start the chainsaw engine
  • If the engine starts and fuel is sucked in, then this indicates the serviceability of the gasket.

If the fuel is NOT sucked in, then the crankcase gasket needs to be replaced.

Carburetor. This is the most important and most difficult part of a chainsaw. If all of the above steps did not help to Get a positive result, then this indicates that the carburetor is faulty. The main malfunction of the carburetor is the clogging of its channels and nozzles. Membranes and other elements fail less often. In any case, you will need to disassemble the chainsaw carburetor, clean it and replace the failed parts.

As you can see, there are enough reasons that the chainsaw does not start. To find out what exactly happened in your case, you need to remember the symptoms the day before. Perhaps before the chainsaw stopped starting, engine malfunctions were observed, power and performance decreased, and other breakdowns were also appropriate. Based on THESE technical symptoms, it is necessary to start the search. If you do not know where to start, then the diagnostics should be carried out in order, as described in the material.

Exhaust duct or muffler cleaning and influence on engine starting

When the chainsaw is operating, resinous deposits are deposited on the walls of the exhaust duct and muffler. Nagar. Periodically, this carbon deposit needs to be cleaned, but most tool owners remember this only after the chainsaw does not start. Why is this happening? The reason is that Burnt Food has nowhere to go, so the engine will NOT be able to start. When the exhaust channel is dirty, the chainsaw only loses power, but also its independent engine stops working.

Deposits on the muffler walls are caused by the following factors:

  • Use of low-quality gasoline and oil
  • Incorrect gasoline to oil ratio when mixing
  • Long-term use of the tool without preventive measures

There is no difficulty in cleaning the muffler of the chainsaw. The cleaning sequence is as follows:

  • To begin with, unscrew the screws securing the muffler
  • The cooling panel with a gasket is dismantled
  • Next, you need to remove the spark arresters
  • The resonator case is disassembled
  • All elements are cleaned and washed from carbon deposits with kerosene or other cleaning fluids. This must be done exclusively with a respirator and glasses. Carcinogenic substances are very dangerous for humans
  • Wait until the cleaned elements dry
  • Assemble in the reverse order of removal.

When cleaning the walls of the outlet channel, it is necessary to close the cylinder opening with a rag. This will eliminate the possibility of dust and sand getting into the cylinder. After cleaning the muffler and the exhaust duct of the chainsaw, you can start starting the engine of the tool. At the same time, you will Feel how the chainsaw will work at full power.

Checking the spark plug and the gap between the coil and the magneto

Spark plug. This is the most important part that is responsible for the ignition of the fuel mixture supplied to the cylinder chamber. If the candle has served its purpose, then it will give out a weak Spark or NOT at all. You can check this in the following way:

  • Unscrew the spark plug
  • Put it on the cylinder by connecting it to the candlesticks
  • Switch on ignition
  • Pull the starter handle

If the spark occurs constantly, then this indicates the serviceability of the candle. And it is correct Not only the spark plug, but also the ignition system. Coil and high voltage wire. If a spark occurs on the spark plug, but intermittently (Intermittently), then such a part must be replaced. First you need to check the gap between the contacts. The gap should be between 0.5 and 1 mm.

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For each model of a chainsaw, manufacturers indicate the recommended gap size, so you need to use a reference book. You can measure the gap with a special probe or a letter of paper folded several times.

The absence of a spark on the spark plug indicates a malfunction of the ignition system, therefore, before replacing a part, you should make sure that the ignition coil and high-voltage wire are in good working order. The chainsaw may not start due to clogged spark plug electrodes. Black carbon deposits or wet electrodes. All this may indicate the following malfunctions:

  • Black carbon deposits. Chainsaw carburetor not adjusted correctly. The mixture entering the cylinder contains a lot of fuel and little air. You can eliminate the malfunction by cleaning the carbon deposits on the spark plug electrode and then adjusting the carburetor
  • If the candle is wet (it floods), then this may indicate the following. Either the ignition system is faulty (including the spark plug itself), or an excess amount of fuel enters the cylinder, thereby filling the spark plug. First you need to make sure that the spark plug gives a good spark, and only then adjust the carburetor. It is not recommended to dry a wet candle by calcining, so it should be wiped dry and then allowed to dry in the sun
  • If the spark plug has a red or pink carbon deposit on the electrode, this indicates that the gasoline used contains a large amount of additives. Typically, this effect is produced by AI-95 and higher gasoline, an increase in the octane number in which is achieved by adding additives

When the candle is brown (brick), then this is talking not only about a properly adjusted chainsaw carburetor, but also about the health of the ignition system. If a new spark plug is used, which, when checked, produces a weak spark (or there is no spark at all), then this is a sign of a malfunctioning ignition coil. The coil must be replaced together with the high-voltage wire.

Searching for reasons why the chainsaw won’t start

Amateur and professional chainsaws are complex devices. The service life of their two-stroke engines, components and assemblies has its own limitations. For this reason, quite reliable and expensive tools, along with cheap Chinese units, periodically fail and refuse to start. The situation when the chainsaw does not start or stalls is not very pleasant and sometimes confuses the user. How to identify and eliminate the malfunction, returned the tool to work.

Restoring the work of the tool

To restore the saw, it does not matter whether the Ural or Stihl brand, you need to know the location of the breakdown.

First, we check and change the unusable fuel mixture. If the saw still does not start, then check further point by point.

The problem is the candle. We pull out and dry. In no case should you pierce it, because this will lead to a malfunction of the part. After 30 minutes after drying, you can put the plug back in, before that check if there is any fuel left in its place.

In addition, the candle can simply break, so it is better to have a spare one to exclude the cause.

Another prerequisite for the fact that the tool does not start well and stalls is poor contact between the spark plugs and the high-voltage wire. If everything is in order here, but there are still sparks. Perhaps the ignition unit itself has broken. Such a breakdown can only be corrected by replacing it.

The air filters should be checked and cleaned from time to time. If from the moment of purchase you have NOT checked it, then it could become clogged with dust and the floor is a prerequisite for a malfunction.

In models such as Stihl 180, Ural or Partner 350, the breather is clogged, which often leads to breakdown. You can use a sewing needle to clean it.

Stihl 180, Druzhba, Ural and Husqvarna 142 models sometimes have muffler clogged, it also needs to be checked and cleaned.

If the problem is in the carburetor, then without experience, it is not worth trying to fix it. It is best to turn to specialists.

If, after checking and eliminating the above problems, your saw still does not start, then most likely the breakdown lies in the CYLINDER group.

When, upon inspection, you see damage and chips on the piston or cylinder assemblies, then these elements will have to be replaced.

If the reason for the malfunction of the chainsaw is the pipes, which are leaking, then most likely an insufficient amount of lubricant is supplied to the chain. To eliminate the problem, only the tubes are replaced, and the joints are covered with sealant.

The details of the mechanism cannot last forever, so they will have to be changed periodically. To find out how long which part serves, you need to look at the instructions.

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 lumber and logs. Most often this occurs 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.

A resonator clogged with carbon deposits can cause a poor start of a gasoline saw.

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

Chinese Chainsaw Won'T Start
  • Remove the muffler by unscrewing the screws;
  • Remove the cooling panel and gasket;
  • Remove spark arresters;
  • Let’s disassemble the resonator body;
  • Wash all elements from carbon deposits with 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.

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Determine the availability of fuel and its supply.

First you need to make sure that there is a fuel mixture in the tank of a chainsaw that does not want to start, and it regularly enters the carburetor. With a full tank, we check how the mixture is fed through the gas line. Disconnecting the fuel system pipe from the carburetor and trying to pump up. In the case of a complete order, when pumping, gasoline will be supplied in a jerk in accordance with the norms set by the manufacturer. Poor or no fuel supply can result from:

  • The fuel supply channel is clogged;
  • Debris-killed fuel filter.

Often a prerequisite for a poor start of a chainsaw may be too full a tank. In this case, pay attention to the presence of smudges under the saw case cover. If present, see the connection of the gasoline feed pipe to the carburetor. Most often, it is squeezed out by pressure when the tank cap is screwed on, refueling under the very neck, which prevents the engine from starting.

The quality of the fuel mixture can also be one of the reasons why the chainsaw does not start. If, after completing the work, DO NOT drain the remaining gasoline, and leave the tool for long-term storage (more than 2 weeks), then the processes of resin formation and polymerization of the components will begin to occur inside the tank. What can be a prerequisite for the appearance of carbon deposits on the piston, rings and cylinder liner. Therefore, always prepare the mixture only in the required amount before work.

Identification and elimination of obvious faults of the chainsaw.

To determine the reason why it does not start or stalls when starting the chainsaw, it is necessary to troubleshoot the tool. The essence of the procedure is to consistently inspect the condition and operation of the main working elements of the saw motor. At this stage, we check:

  • Spark plug present;
  • Fuel supply;
  • Filter status;
  • The operation of the breather of the stalling unit built into the fuel cap;
  • Discharge duct function.

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, which prevents the flow of gasoline into 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 out 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 for the identification. 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.


This is a fragile element of a chain saw that needs delicate debugging. If you have checked all of the previous items and they are working properly, start cleaning the carburetor. Contamination of it destroys the entire machine. Lay out a clean cloth on the work surface and gradually, piece by piece, we will disassemble this mechanism.

Clean off dust, tar and carbon deposits from it using Special Liquids. A nozzle cleaner is suitable. Then Reassemble the entire mechanism. If necessary, write down the order in which you removed the parts or lay them out on the table in order. The cleaned carburetor will start to function.



This element of the device is often overgrown with resinous deposits, which accumulate on it during the combustion of the fuel mixture. At the same time, the power of revolutions decreases, sometimes to complete inoperability. To clean the exhaust duct and muffler, remove them, remove the cooler and seal from the housing, disassemble the spark damper and resonator. All items removed from the case Wash in warm soapy water, dry and put back.

Dry cleaning of this element is unacceptable, as substances harmful to human health accumulate on it.

Fuel quality

It all depends on you. Read the instructions, read what quality gasoline is required for normal operation of the saw, And do not save on the power of this mechanism. Its gasoline consumption is low, and fuel with a low octane number will quickly “kill” it.

Insufficient chain lubrication

The reason for this may be clogged hoses, their deterioration and, as a result, leakage. A poorly lubricated chain and disc will wear out quickly. Check if the oil supply is good. Run dust and direct it onto a blank sheet of paper. If there are microscopic droplets on it, flying off the rotating chain, everything is in order. If the letter is dry, you need to clean out the hoses that supply lubricant to the disc and chain. Be sure to check the joints and joints of parts with hoses. Leaks must be cleaned, degreased and treated with a sealant.

Hoses and connections

These elements of the device are quickly frayed and worn out, as they are flexible and transport the fuel mixture. Hose leaks are fraught with the fuel mixture flooding the tool, and such breakdowns can only be repaired at a service center. As for the connections, it is better to check them for a tight fit immediately after purchase. Hoses have a certain service life.

After its expiration, they must be replaced. This applies to used hoses. If you check the hoses and connections and find leaks, remove the used element and replace it with a new one to avoid serious damage. You can check them by pumping the fuel mixture after disconnecting from the carburetor.