Husqvarna chainsaw starts and stalls cause

Fuel supply system

If fuel does not flow into the tank of the chainsaw, then there may be two reasons for this:

• Clogged filter.
• Lid clogged.

In this case, the fuel is not supplied in full, and the tool does not start or starts and immediately stalls. The repair consists in cleaning the air filter and cover.

The filter must be removed very carefully so that dirt that clogs it does not get into the carburetor. It can be cleaned and washed with ordinary detergents.

Chainsaws “Husqvarna”. major faults

The Swedish manufacturer’s tool can turn hard work into a simple task. Chainsaw models Husqvarna 137, Husqvarna 240 and Husqvarna 365 are distinguished by three features:

• high engine power;
• improved engine filtration system;
• the ability to absorb unnecessary vibrations.

If the tool is operated strictly according to the instructions and its malfunctions are eliminated in a timely manner, then it will delight with reliable and stable operation. Correctly carried out repairs with original spare parts will allow you to use the saw for a long time.

The main reason for a chainsaw breakdown is most often engine failures, which can manifest as follows:

• do not start;
• unstable work at idle;
• start up and immediately stall;
• not have enough power.

In this case, the malfunction should be sought in the ignition system, piston group or fuel system. Often the reason for poor performance of the tool can be associated with the clutch, brake system, lubrication mechanisms, tire.

Chainsaws internal combustion engine characteristics

The main malfunctions of chainsaws are associated with engine failures. Domestic and foreign manufacturers use single-cylinder two-stroke internal combustion engines as a chain drive. The design of the motor is simple. The ignition is conventional, without the installation of capricious electronics. Chainsaw engines operate reliably in various climates. Fuel for a carburetor engine is obtained by mixing AI-92 gasoline and special oil. Since there is no oil pump in the design, the piston and cylinder are lubricated with a mixture of gasoline and oil. The saw motor develops power from 2 to 5 kW, and the crankshaft rotational speed reaches 14,000 rpm. At such high rpm and load, the oil requirements are special. Use the oil specified in the instructions. When changing the oil to a conventional motor tool, the tool life is sharply reduced. Remember that filling the tank with gasoline without adding oil is strictly prohibited.

Husqvarna 240 chainsaw starts and stalls

Hello! If you are on this page, then, most likely, your chainsaw stalls when you press the gas, and you want to know why this is happening and what to do about it. Well, I will try to help you with this problem by examining the most common causes of such a misfortune, as well as methods of eliminating them.

To begin with, I will immediately write for novice users that many chainsaws require warming up the engine at idle speed for about one minute before work. Saw may stall when gas is added while engine is cold.

So, if a heated chainsaw can idle, but stalls under load, then this means that:

• improperly tuned or clogged carburetor. the most common case;
• it does not have enough air, the consumption of which increases sharply with increasing speed. this means that the air filter is dirty (a rare case, since the filter becomes clogged gradually, so the user first notices a loss of power);
• it does not have enough fuel, the consumption of which also increases with increasing speed. this means that the fuel filter is dirty (also an infrequent case);
• Well, the most unpleasant case is if there is excessive friction between the piston and the cylinder wall due to a lack of oil in the fuel mixture. after such a chainsaw operation, you will most likely fly into the repair of the piston group, since seizures form on the piston and cylinder walls that prevent saw operation.

Let’s look at these cases separately.

Tools and materials

Chainsaw two-stroke engine diagram.

The design of the mechanical units of chainsaws is characterized by good reliability and maintainability. Almost all units and parts have free access. With the necessary equipment, they can be easily removed for repair or replacement. To disassemble and check the life support systems of the chainsaw engine, you should stock up on the following tools and materials:

• a set of fitting and assembly tools;
• socket wrench;
• tester;
• pressure gauge for measuring compression;
• probes for measuring gaps;
• needle;
• sandpaper;
• fuel mixture (gasoline oil);
• rags.

How I Fixed my Bogging Chainsaw by @GettinJunkDone

Fuel filter dirty

If the option with an air filter did not suit you, then we try to change the fuel one. It is located in the gas tank and is attached to the hose through which fuel is taken from the tank.

This hose must be gently pryed with something and removed from the gas tank its edge, on which the filter is fixed. Here, the option with work without a filter, as in the case of an air filter, it is better not to use it, since you cannot know for sure if there are any unnecessary impurities in the fuel.

Husqvarna 240 won’t stay running

Fuel filter

Therefore, we simply change the fuel filter to a new one and try to work. If everything is fine, then congratulations. you have found the reason.

Cleaning and adjusting the carburetor

If all of the above did not help, then, most likely, adjustment or cleaning of the carburetor is required. It is not recommended to do these procedures on your own, since most often such attempts still end with a trip to the service. So it’s better to go there right away and not disassemble anything on your own. But if you still want to dig deeper yourself, then it is best to watch a video that shows how experts do it:

I will end on this. Thanks for attention! Read more articles on this site! Until next time!

Using a chainsaw makes hard work easier. But sometimes the chainsaw starts and stalls, the reason for this can be any. What to do? You have to choose: take it to the workshop to specialists or try to repair it on your own. We will try to help the reader understand the reasons for the refusal, ways to eliminate breakdowns and give advice on the operation of chainsaws. In turn, it will be useful for the owner to familiarize himself with the factory operating instructions and the design features of his chainsaw. This information will help him to correctly use and professionally repair the tool.

Chainsaw device diagram.

What to do if the engine stalls after starting?

We often observe a short operation of the saw after starting. the chainsaw stalls almost immediately. This malfunction has characteristic symptoms. The list contains the probable causes of the malfunction and how to fix it:

• Lack or small amount of fuel. If a failure occurs when sawing in an inclined position, then this indicates a rise in the intake tube above the fuel level. Check for fuel in the tank. Fill up with gasoline to the required level.
• Poor quality fuel mixture. Prepare fuel in strict accordance with the saw manufacturer’s instructions. Replace the mixture completely.
• Breather clogged. Low fuel consumption to the engine. Breather is a breathing hole in the tank lid. Clear the blockage with a needle.
• Poor contact of the candle with the high-voltage wire cap. In this case, the porcelain insulator of the candle becomes very hot. Strip the contact and put the “cradle” firmly on the spark plug.
• Defective spark plug. Replace with a new one or a known good one.
• The muffler is clogged with combustion products (exhaust gas). The muffler needs to be cleaned.
• Carburetor not adjusted. To adjust the quality of the mixture, the carburetor has 3 screws: “L”. fine tuning, “H”. coarse adjustment of high speed and “T”. adjustment at idle. Observing the sequence of adjusting the screws, we achieve higher crankshaft revolutions.
• Clogged air filter. Air enters the carburetor in a small amount. we get an enriched mixture. The saw will stall as the load increases when cutting hardwood and large diameter trunks. Rinse the filter in warm water and dry.
• Failure of the piston group. Replace defective parts.

Now you can independently find and eliminate the reasons due to which chainsaws start and stall, the reasons for their stop. Recall that a chainsaw develops a high speed of movement of the working body (chain) and is considered a dangerous cutting tool. Strictly follow the safety rules when performing work, maintenance and repair of the chainsaw.

Chainsaws, simple in design and reliable in operation, are very popular among owners of private houses and summer residents. When handled correctly, this tool will last a long time and rarely break. over, it will not be difficult to eliminate the cause of the chainsaw malfunction with your own hands, especially if you know where to look for the cause.

The reason for stopping the chainsaw in the midst of work may be:

• poor quality of component parts and whole units;
• unskilled care;
• the use of low-quality fuel and oil substitutes;
• illiterate exploitation.

Remoteness from maintenance services and the high cost of the provided repair services, forcing the owners of failed tools to restore their functionality on their own.

This option is possible only after the end of the warranty period. The difficulty lies in the fact that traces of dismantling of individual components and assemblies noticed by service specialists can be the fault of refusal to repair more complex and expensive parts for free.

The chainsaw starts and stalls. the reason

If the chainsaw starts and stalls at the first attempts to do the job, then the reason may be problems with the chain brake or its jamming due to lack of lubrication. In this case, the oil level is measured. If the amount of lubricant is sufficient, then the cause may be in the tube that leads it to the lubricating mechanism.

Another reason may be a broken carburetor. If he only needs adjustment, it can be done independently in accordance with the instructions. If the carburetor needs cleaning or repair, then you cannot do without the help of professionals.

Another possible cause of this malfunction is a low fuel level in the tank. In this case, the saw stalls when tilted, since the remaining fuel mixture ends up in the part of the tank opposite to the place where the suction tube is located.

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 idling. 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 in the carburetor is detected, the cause can be eliminated by installing a repair kit of gaskets.

Only after the above actions have failed and the crankcase with the carburetor is sealed, you can proceed to adjust 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.

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 discusses the consequences of its malfunctioning HUSQVARNA 142.

Why the chainsaw starts up and immediately stalls

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. 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, inside the engine at the time of its malfunctioning, processes will take place that irreversibly lead the saw to the most serious consequences, for example, the piston melting, crankshaft jamming.

An easy way to determine the quality of a mixture

The easiest and most affordable way to check the quality of the mixture is the spark plug center insulator. Brown color of any intensity indicates correct carburetor adjustment.

The result of working with a rich mixture is the formation of black carbon deposits on the insulator, a lean mixture manifests itself as a pure insulator of white or light gray color.

If, after normal start-up and warm-up, the fuel-filled saw periodically stalls during operation, it is recommended to eliminate the vacuum in the gas tank by cleaning the breather. The reason for the unstable operation of the engine may be condensate water that has got into the carburetor float chamber.

Why does a chainsaw stall when heated

It often happens that the chainsaw starts up on a cold one, but stalls during the heating process. This behavior of the tool can be caused by the following reasons:

• The carburetor is incorrectly set. This problem can be identified by how the device is started up on a cold one. If it is performed without closing the air damper, and the engine starts without a preliminary flash, this means that after heating the engine, the fuel fills the candle. The solution to this problem is to adjust the carburetor. Details on carburetor adjustment
• Coil (ignition module) malfunction. This problem can be identified by sequentially checking the spark, first on a cold, and then on a hot motor. If there is no spark on a hot engine, then you need to replace the ignition coil.
• Defective spark plug. In this situation, as in the case of a malfunction of the ignition module, the spark disappears when the engine heats up. It is necessary to replace the spark plug with a new one, and if this does not lead to a solution to the problem, then the ignition module and the distance between it and the flywheel should be checked.

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.

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 jamming 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 flow 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.