What to do if the chainsaw won’t start

Reasons for malfunctioning chainsaws

If the chainsaw does not start, then you need to conduct a step-by-step diagnosis. It is recommended to go from simple to complex and do everything in order. Although devices from different manufacturers differ from each other, they have the same principle of operation and layout: they are based on a two-stroke gasoline engine, which turns a tensioned cutting chain through a gearbox.

Diagnostics must be carried out sequentially:

  • Filter inspection.
  • Checking the electrical system (there is a spark on the electrode of the candle or not).
  • Revision of the fuel supply and breather, which is built into the fuel tank cap.
  • Exhaust duct investigation.

Each of the four stages must be considered separately.

What you need for repair:

  • Set of car wrenches, drivers and heads.
  • Screwdrivers: Phillips and slotted, flat spatulas for cleaning parts.
  • Metal brush (cord brush) and brushes with hard bristles.
  • A bowl for washing parts (a cut plastic canister is suitable).

It is recommended to use a compressor to purge the motor parts. The use of technical gases (especially oxygen) is prohibited.

Filters

If the chainsaw has been working for a long time, then the air or fuel filters may become clogged. In the first case, the required portion of air will not enter the cylinders, the combustion of the fuel mixture will not occur. If the fuel system is clogged, the supply of the gasoline mixture will stop.

The air cleaning element should be removed carefully, dust should not enter the carburetor. The element needs to be blown out, washed with soap and water, dried and put back in the same way.

To check the condition of the fuel filter, you need to remove the hose from the carburetor, try to pump fuel manually. If the trickle is too weak or completely absent, then the filter needs to be replaced or washed. You can purchase a new one from your dealer, or contact power tool repair shops.

Gasoline supply. Breather

First you need to prepare a workplace:

  • Remove dirt and dust from the workbench.
  • Prepare clean rags, brushes, containers for washing small parts.
  • If there is a compressor, prepare it for purging the carburetor passages.

The chainsaw itself needs to be cleaned and blown off with compressed air. Now you can start diagnostics.

  • Fuel tank. inside should be free of dirt, iron filings, sand and other impurities.
  • A breather built into the lid. air must enter the tank through it, otherwise a vacuum will be created during operation and fuel will not enter the carburetor.
  • Hoses and pipes. for cracks and other defects. If you suspect, replace.

After assembly, it is required to check: if, as a result of manual pumping with the feed pipe removed from the carburetor, the gasoline mixture flows in a dense stream with jerks, then the system is working. If the chainsaw still does not start, then the carburetor is to blame.

Chainsaw won’t start: what to do?

Modern chainsaws are quite capricious devices, although the creators use the same technologies in their production. The problem is in the materials used. According to independent sources, a tool for sawing wood of an average price category serves 500-1200 hours, professional devices. up to 2000, and sometimes even longer. At the same time, it is important to follow the manufacturer’s recommendations: service the equipment in a timely manner, observe a certain operating mode, fill in high-quality fuel and oil.

Outlet channels

You may need to clean the exhaust ports on your chainsaw.

After prolonged use of the chainsaw, the exhaust channels could become coked, due to which there is opposition to the translational movement of the piston. Simply put, not removed gases slow down the engine.

  • Remove the muffler of the chainsaw.
  • Remove the gasket carefully.
  • Dismantle the spark arrester.
  • Disassemble the housing (if possible) of the resonator.
  • Clean the parts with detergent solutions (kerosene, WD-40) and mechanically.
  • Wipe, dry the nodes.
  • Assemble the system back.

Candle check

The operation is similar to that carried out by all motorists with gasoline engines. If there is a new and 100% working candle in stock, then the easiest way is to put it on and try to start the chainsaw. At the same time, the old one should be inspected: heavy carbon deposits indicate that the engine is not working correctly. If there are no deposits, it is possible that the gap between the electrodes was violated, due to which the spark stopped forming or was too dim. The distance between the contacts varies between 0.2-0.5 mm.

  • Errors made when adjusting the carburetor.
  • Too much oil added to the mixture.
  • Remove high voltage wire.
  • Unscrew the candle and attach the previously removed wire back to it.
  • Lean the “skirt” of the candle against the unpainted part of the cylinder.
  • Try to start the engine.

You can try to disassemble the ignition unit, clean the contacts, dry, assemble and try again. A number of faults cannot be eliminated, therefore, in some cases, the unit will need to be replaced, but this is an extreme measure.

What to do if all else fails?

If the chainsaw still does not start, and it was not possible to identify the causes and remedies, then this is a reason to visit the service center. But if he is not nearby, then you can try to perform a number of other actions, all this at your own peril and risk.

Sometimes the only way out is to contact the service center for help.

What else could be the reasons for the malfunctions:

chainsaw, start
  • Low compression ratio in the cylinders. if the compression rings are worn out or deformed, then there is an excessively large gap between them and the cylinder walls. Because of this, the fuel mixture does not burn, but seeps out.
  • The carburetor is not tuned. it is difficult for an amateur to properly adjust the device, but it’s worth a try.
  • Mechanical faults. if extraneous sounds were heard before the breakdown: grinding, clanking, ringing, then the internal parts of the engine are probably destroyed. Without experience in overhauling two-stroke engines, it will be extremely difficult to do something.

Compression is measured using a device of the same name (compressometer). It is screwed in instead of the spark plug, after which you need to try to “start” the engine. The reading that appears on the dial will be the actual compression value. The nominal value will have to be found in the documentation for the engine.

If there is no compressometer, then we do this:

Finding 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 correct a malfunction by returning the instrument to work.

Checking the condition of the fuel and air filters.

If everything is in order with the fuel quality, the chainsaw engine may not start due to clogged fuel and air filters. To diagnose these elements, it will be necessary to perform a number of manipulations associated with their dismantling.

  • Disconnect the gasoline supply channel from the carburetor;
  • Pump up fuel.

If there is little or no pressure in the branch pipe, disconnect the filter. Before this, free the tank from the mixture and remove the filter element itself. Dismantling is done with a wire hook. A clogged replacement cartridge that causes a poor starting of the chainsaw engine can be cleaned, but it is best to replace it with a new one. When using the tool in dusty conditions, it should be cleaned on a regular basis.

A clogged air filter can cause the chainsaw engine to run erratically, making it stalling or difficult to start. Dust and dirt deposited on the adsorbent material make it difficult for air to enter the system, make the fuel mixture so rich that it will sometimes be difficult to start the tool.

chainsaw, start

Checking the air filter is one of the first steps in finding the cause of a poor start.

Care should be taken when removing the air filter, as dust accumulated on the surface of the saw during operation can enter the carburetor. And this is fraught with more expensive repairs. After detaching the cartridge, thoroughly clean it of accumulated dirt and rinse it with the addition of detergent. Dry the element and put it back in place just as carefully.

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 cause of 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 it starts, 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.

Identifying and eliminating obvious chainsaw malfunctions.

To determine the reason why the chainsaw does not start or stalls when starting, 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 engine. 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.

to the content

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. We disconnect the fuel system pipe from the carburetor and try to pump it up. In the case of a complete order, when pumping up, gasoline will be supplied in jerks in accordance with the norms set by the manufacturer. Poor or no fuel supply may result from:

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

Often the reason for a poor start of the chainsaw can be a tank that is too full. In this case, you should 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, which is filled 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, the remaining gasoline is not drained, and the tool is left 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 cause carbon deposits on the piston, rings and cylinder liner. Therefore, always prepare the mixture only in the required amount before work.

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

The first step in looking for reasons why your 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 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 that affect 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:

Top Reasons Chainsaw Won’t Start — Chainsaw Troubleshooting

  • 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.

Top 5 Reasons A Chainsaw Won’t Start

How to start a cold chainsaw if the candle 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 carried out 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.

Why does a chainsaw start badly?

There may be several reasons why the saw does not start well. It is necessary to check them one by one, excluding one after another, approaching a guess. The simplest reason is lack of fuel or ignition off. So, you can fill the tank with a fuel mixture and check the start of the ignition system. If this does not help, proceed to checking the condition of the spark plugs. The absence of spark from spark plugs is most often explained by 2 reasons carbon deposits have accumulated on the candle, which must be cleaned off candles wet from gasoline. The first sign of this is a strong smell of gasoline near the candle. The candle can be dried with a rag, having previously unscrewed with a key, or simply wait 10-15 minutes until the mixture disappears. If the spark plug gets wet frequently, it is necessary to determine the reason why too much fuel is being supplied. It also happens the other way around, when the candle is dry, and there is not even a smell of fuel near it. The reason for this is that the mixture does not reach the combustion chamber. This process needs to be restored to resume work.

Do not forget that candles are consumables and require periodic replacement in the event of a malfunction. The air supply also plays an important role in starting. To eliminate the problem, remove the air filter. If necessary, clean it or sopun if available. The muffler may also need cleaning. Soot and carbon deposits accumulated in it affect the work. The last thing to think about is the wrong fuel mixture. But this is what can serve as a bad plant and poor quality work. complex breakdowns are not recommended to be performed by yourself; for their solution, you should contact the nearest service center.

Air intake and muffler condition

The cause of a problem start may be a clogged air cleaner filter with sawdust. If the engine starts with the air intake removed, special attention should be paid to cleaning the filter. A large amount of carbon deposits in the muffler affects the power and thrust of the power unit, but the engine should start without much effort.

Checking the tightness of the connection between the carburetor and the body

When the threaded fasteners are loosened, air is sucked in, which leads to a depletion of the gasoline-air mixture and, accordingly, a deterioration in its performance.

To replace a damaged gasket, it is recommended to use a repair kit, if it is not available, a gasket can be made from a gasoline-oil-resistant material identical in thickness.

Checking the condition of the fuel and air filters.

If everything is in order with the fuel quality, the chainsaw engine may not start due to clogged fuel and air filters. To diagnose these elements, it will be necessary to perform a number of manipulations associated with their dismantling.

Chainsaw Won’t Start (Easily Fixed) Must See!

For the fuel filter:

  • Disconnect the gasoline supply channel from the carburetor;
  • Pump up fuel.

If there is little or no pressure in the branch pipe, disconnect the filter. Before this, free the tank from the mixture and remove the filter element itself. Dismantling is done with a wire hook. A clogged replacement cartridge that causes a poor starting of the chainsaw engine can be cleaned, but it is best to replace it with a new one. When using the tool in dusty conditions, it should be cleaned on a regular basis.

A clogged air filter can cause the chainsaw engine to run erratically, making it stalling or difficult to start. Dust and dirt deposited on the adsorbent material make it difficult for air to enter the system, make the fuel mixture so rich that it will sometimes be difficult to start the tool.

Checking the air filter is one of the first steps in finding the cause of a poor start.

Care should be taken when removing the air filter, as dust accumulated on the surface of the saw during operation can enter the carburetor. And this is fraught with more expensive repairs. After detaching the cartridge, thoroughly clean it of accumulated dirt and rinse it with the addition of detergent. Dry the element and put it back in place just as carefully.

Checking the supply of the combustible mixture and the ignition system

First of all, you should make sure that there is fuel in the carburetor float chamber. After several attempts to start the engine, an unscrewed dry candle will tell you that the reason for the poor start is in the absence of a combustible mixture.

Recommended sequence of actions:

  • checking the fuel filter;
  • the patency of the gas line;
  • the cleanliness of the drain hole of the fuel tank cap;
  • freezing of the carburetor float valve in the closed position is not excluded.

To clean the volume of the cylinder, it is necessary to make several energetic jerks with the starter with the spark plug removed and the ignition off. In the absence of a new, obviously working candle, it is necessary to dry thoroughly and check the old one for a spark. Heating it up over an open fire is not desirable, since there is a high probability of the formation of insulator cracks and its complete failure.

To check for sparking, a spark plug with a cap on must be attached to the saw body and crank the crankshaft with a starter. A working candle gives out a strong discharge, accompanied by a characteristic crackle.

A small spark with a red tint indicates a malfunction of the ignition unit, high-voltage conductor or internal resistor of the standard candlestick.

What to do if the chainsaw won’t start

Even the most expensive garden equipment can break down. But if the chainsaw does not start, this does not mean that it is time to buy a new one or pay for the expensive services of repairmen. Most of the problems associated with this problem are not global and can be easily fixed by hand. The main thing is to correctly determine the reason why the chainsaw refused to properly perform its functions.

Filter problems

Dirty filters are one of the main factors that prevent your chainsaw from starting. Check the air filter for cleanliness, it is located under the housing-cover. The fuel cleaner is located directly in the fuel tank.

Air filter and spark plug location

In addition, you should inspect the breather in the gas tank. For diagnostics, remove all possibly clogged parts for a while, start the device without them.

Troubleshooting options and remedies

Whether your chainsaw is Champion, Husqvarna 236 or Patriot, the reasons for poor performance are identical. There are a lot of options for why the STIHL chainsaw does not start, but the most common are the following.