The chainsaw only works at high rpm

Shoots at the muffler:

  • Enriched air-fuel mixture. Why does the chainsaw “shoot”? There is too much gasoline and too little air in the mixture, so the mixture does not completely burn out in the chamber and partially burns out in the muffler. Exhaust carbon deposits are a clear sign of this. Air filter cleaning or carburetor adjustment required.

The engine “shoots

If during operation there are extraneous sounds similar to shots, then there is a problem with the muffler or carburetor. How do I keep my chainsaw quiet? It depends on which node the fault is in.

Stalls immediately after launch:

  • The fuel mixture is not prepared correctly, there is too much oil in it, so the octane number of gasoline is less than it should be, so the chainsaw only works on suction or immediately stalls.
  • Spark plug carbon or improper spark plug-to-wire gap.

Engine stalls

The engine starts, but at idle or under load, the chainsaw stalls. In this case, most often you should perform the same actions as described above.

chainsaw, only, works, high

How to adjust your chainsaw depends on exactly when the problems begin:

Chainsaw saws to the side

When sawing, you will notice that the cut is uneven. Why does the chainsaw cut crooked? There are several reasons:

  • Incorrect chain sharpening. The teeth are sharpened at the wrong angle or in one direction only. Correct sharpening required.
  • Incorrect chain. At very high revs, the difference of even 0.2-0.3 mm between the width of the groove or the width of the landing will be visible, which is why the chainsaw cuts to the side. An appropriate circuit must be installed.
  • Uneven tire wear. Over time, the tire wears out on one side and then the chain is pulled to the side. Flip the tire regularly so that the wear is even on both sides. If the wear is too great, replace the tire.

Chainsaw won’t start

If there are difficulties with starting a chainsaw, many immediately sin on the carburetor. In fact, there are several options and the cause of the malfunction can be any:

  • Clogged air and / or fuel filters. The problem is solved by cleaning the filters.
  • Lack of fuel in the tank. Yes, there is such a reason. some owners forget about such an insignificant detail as refueling a chainsaw and think that a couple of liters of gasoline will last for six months. In addition, the fuel in the tank should not be stored for more than 14 days, because gasoline evaporates and octane number is lost.
  • Check the pipe from the fuel tank to the carburetor. it could be clogged or cut off, so gasoline does not enter the tank.
  • No spark on spark plug. Why there is no spark. there can be many reasons: there is no contact, you need to change the candle or it is flooded. Why pours a candle on a chainsaw is another question. But if this happens, you need to dry and reinstall, and then check for a spark. If the spark plug is heavily soaked, it is recommended to replace it.
  • Check muffler for carbon deposits. If there is carbon deposits, thoroughly clean the muffler, but it is still recommended to take the chainsaw to a service center to check the cylinder and piston there, because carbon deposits are a sure sign of improper operation of precisely the elements of the cylinder-piston group.
  • The carburetor is clogged. How to properly adjust the chainsaw so that the carburetor works well was discussed in a separate article.

If none of the above methods helped, then the reason is more serious. the breakdown of one of the nodes of the connecting rod-piston group. In this case, it is recommended to take the chainsaw to a service center.

Stalls at maximum speed and works only on suction

  • Clogged air or fuel filter. Seals need to be cleaned and checked.
  • The breather is clogged and because of this, fuel does not flow and the pumping of gasoline on the chainsaw does not work. Take the needle and gently clean the breather.
  • Fuel pump malfunction. Remove the pump and check if gasoline is oozing out of it. If oozing. replace the gasket or the pump itself.

10 do-it-yourself chainsaw malfunctions

Even professional chainsaws from world famous manufacturers break down. no one is immune from this. The question is how often breakdowns occur and how serious they are. It is one thing to sharpen the chain or replace the drive sprocket, and another thing if the chainsaw does not start or fires at the carburetor. In fact, most of the malfunctions can be easily eliminated with your own hands, for example, when the chainsaw does not lubricate the chain or stalls.

Reasons for malfunctioning

There can be several reasons for reducing power and reducing rpm. Let’s list some of them:

  • Incorrect ratio of oil to gasoline in fuel. If there is not enough oil, then the cylinder walls are not lubricated and scuffs appear. If there is an excess of oil, then in this case the engine does not gain power. The saw emits excessive smoke during operation.
  • Incorrect carburetor operation. This is due to incorrect adjustment. The working mixture comes of poor quality. The engine gets stuck with fuel, and the chainsaw stalls when you press the gas, or, conversely, there is not enough gasoline.
  • Spark plug electrode burned out. The motor runs intermittently. Strong vibration appears.
  • Lost contact in the electrician of the tool. In this case, the saw will not start at all.
  • The air filter is clogged. The engine does not develop power and stalls at idle speed.
  • Clogged petrol filter. Insufficient flow of fuel to the carburetor.
  • Clogged exhaust system. In this case, the power drops to 40%.
  • Wear of the cylinder-piston group. Insufficient compression ratio does not allow developing power. Engine derating occurs.
See also  Chainsaw does not give oil to the chain

Defective fuel supply system

If, during the examination of the spark plug, it was found that liquid is not supplied to the cylinder, then the probable reasons for this fact are found out. They are:

  • fuel is not supplied from the tank due to the clogged hole in the lid (breather), and a vacuum arises inside the tank, which creates an obstacle for the liquid to escape;
  • the fuel filter located in the tank is dirty;
  • fuel fluid from the carburetor does not flow or does not flow into the cylinder in an insufficient amount.

Chain oil supply.

In order to diagnose the first 2 reasons, the fuel hose is removed from the carburetor and it is observed whether or not fuel flows out of it. When it flows out with a full stream, the filter and breather do not look. If it flows weakly or does not flow at all, then it is considered that the source of damage has been found. The breather is cleaned with a needle.

Using a wire hook, remove the fuel filter together with the suction hose through the filling hole of the empty fuel tank. The filter is removed from the latter and cleaned or replaced with a fresh one. Chainsaw manufacturers recommend changing the fuel filter after each trimester.

A weak inflow of fluid into the cylinder from the carburetor or non-observance of the proportions between fluid and air is caused by several reasons:

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

Usually, the procedure for repairing chainsaws is accompanied by cleaning the air filter, since it becomes very dirty very quickly. When this happens, the intake of air into the carburetor decreases, the fuel fluid at the outlet becomes too rich, which leads to interruptions in the normal operation of the engine.

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

Chainsaw centrifugal clutch: 1. friction linings, 2. springs, 3. drum.

By adjusting the carburetor, its misalignment is eliminated. As usual, this is done by means of 3 screws. maximum and minimum revolutions, idling. The adjustment is carried out, strictly adhering to the descriptions in the instructions. The engine will otherwise simply break down. Other manufacturers of chainsaws provide a single idle screw in order to exclude unnecessary interference with the carburetor performance of inexperienced users.

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

The peculiarity of working with it lies in the fact that many small elements of its constituents have the ability to imperceptibly jump off their seats and get lost forever. Having disassembled such a naughty mechanism once without thinking, it can be returned in the same form and not assembled.

If there is little or no experience in carburetor repair, then it is better not to take on it yourself, but entrust this important event to a specialist from the service center. The carburetor is sometimes cleaned there by means of ultrasound.

Trimmer Only Works On Suction

Thank you all for the comments and advice.

If you lift the saw with the bar vertically upwards. and gas in this position. it passes.

See also  How To Start A Chainsaw After A Long Idle Time

If cleaning the muffler did not help to remove the problem, and the engine of your saw is carburetor, then you can try to adjust it. Most engine models have coarse and fine adjusting bolts (H and L, respectively). By increasing the engine speed with their help, you can remove the problem. Keep in mind that adjusting the carburetor is a rather narrow process requiring the introduction of a tachometer.

Fixing a Chainsaw That Won’t Rev. One Possible Cause

The car stalls at idle: possible causes

In order to answer the question of why the saw, at times being capricious, stalls at idle, it must be understood that the basis of this tool is an ordinary two-stroke internal combustion engine.

From this it follows that different problems lead to malfunctions with the main components of any internal combustion engine: fuels and lubricants, the ignition system, the quality of the air-fuel consistency and compression inside the cylinder.

The main motor malfunctions include the following:

Stihl MS290 Dying At Full Throttle

  • the motor does not start
  • starts up, but, working unstably, stalls rapidly at idle
  • the chainsaw works fine at idle, but stalls under load.

There may be different reasons for idling disturbances. But all of them can be reduced to several general positions. So, ICE malfunctions are caused by such difficulties as:

Internal combustion chainsaw engine.

possible clogging of the fuel and air filter

  • lack or problems in the spark plug operation
  • violation in the initial settings of the carburetor, caused by strong vibrations during the operation of the mechanism
  • gas line disadvantages
  • incorrect ratio of ingredients in the “fuel mixture”
  • muffler contamination
  • malfunctions of the cylinder-piston group.
  • Chainsaw stalls when heated. NZIZN.RU

    Why does a chainsaw stall under load

    Chainsaw adjustment, DIY repair of common faults

    By increasing the engine speed with their help, the problem can be eliminated. Keep in mind that adjusting the carburetor is a delicate process that requires a tachometer.


    If the vehicle smokes, its power drops, pay attention to the engine. Its breakdown may also be indicated by an unstable start, overheating.

    Why is the chainsaw heated

    Why does it wear out

    This is one of the questions that chainsaw owners are constantly asking. The answer is easy. Friction occurs on the surface of the headset, which is the cause of wear.

    Contact with rubbing surfaces of dust and dirt, increases wear of parts.

    There is another pressing question: why does a tire wear out prematurely? You can answer it if you study the design of the tire and the principle of operation of the lubrication system, which we will try to do.

    The lubrication system begins with an oil tank, where oil is filled and then, using an oil pump, is transferred to the point of contact of the tire shank with the chainsaw body. To adjust the oil supply, the tool pump is equipped with a special screw. There is a special slot in the place where the tire is installed, which coincides with the hole for receiving grease on the tire. The cause of premature wear may be insufficient lubrication of rubbing parts, which in turn occurs with the following malfunctions.

    • excessive contamination of the oil filter (the first thing to pay attention to);
    • contamination of the oil supply channels on the headset or on the instrument itself;
    • incorrect adjustment of the oil supply by the pump;
    • malfunction of the pump itself;
    • the use of low-quality lubricants or oil that does not meet the requirements of the chainsaw manufacturer.

    To increase service life, manufacturers recommend the use of special oils with high adhesion.

    The choice of the original chain oil is the choice of real men!

    Thanks to this property, at high chain speeds, the lubricant is distributed and retained throughout the tire, and not only on the upper part of it, as is the case with conventional oils.

    It is not permissible to use it as an oil for lubricating used oil from a car engine. In the development there are metal impurities from the car engine, which, falling between the rubbing parts, act as an abrasive tool, and significantly increase wear.

    Oil flows

    Owners of chainsaws often face a problem when oil leaks from below, from under the unit. The reason lies in a damaged oil hose that connects to the pump.

    Saws crooked

    Let’s figure out the reasons why the chainsaw cuts crooked. This manifests itself during cutting under the load of trunks, when the tire is gradually pulled to the side. This is especially noticeable when sawing a wide trunk using the double cut method, first from above, then from below. As a result, the exit is an uneven sawn-off surface, which in some cases is unacceptable. Example. trimming bars.

    • Uneven sharpening of the saw teeth. This is the most common reason the device cuts obliquely. The teeth must be grinded at the same distance to avoid cutting problems. The optimal way out is to purchase a sharpening machine that adjusts to the most worn tooth of the saw mechanism. Or contacting a workshop where such equipment is available. The result is that all teeth are the same size.
    • The used circuit or bus does not match the parameters. When purchasing these elements, the groove width must be taken into account. This is important not only for the correct operation of the equipment, but also for safety when cutting.
    • The saw headset of the device is badly worn out. If the device does not cut well, the headset may wear out. Visual inspection will indicate a problem. If the right or left side of the tire is more worn out, it must be replaced with a new one. With increased wear, it makes sense to carry out a complete diagnosis of the lubrication system. This is often the cause of increased wear on one side of the chain.
    See also  Husqvarna 240 Chainsaw Sprocket Replacement

    In case of complex repairs, it is better to send the equipment to a specialized workshop.

    No spark

    Ignition problems are associated with a weak spark on the chainsaw or no spark. There may be a blue spark when checking the spark plug. This suggests that everything is in order. If spark is missing, check high voltage cable. There may be a wire break in it. Another option, why there is no spark, is associated with an incorrect gap between the ignition module and the flywheel magnetic circuit. The norm for this indicator is 0.2 mm.

    Reasons that lead away from a straight cut

    Sometimes there are situations when it is almost impossible to make a straight cut with a chainsaw, the tire goes to the left or right. The reason for this behavior of the tool may be the following:

    • Incorrect chain sharpening. The teeth of the chain are sharpened more on one side than on the other. You can fix the problem by sharpening the chain correctly.
    • Uneven wear of the chain links, the support pads of the chain links on one side have a large output, because of which the chain tilts slightly and it is no longer possible to obtain a straight cut. The problem can be solved only by replacing the chain.
    • Last but not least, uneven wear. As in the previous case, for this reason, the chain will change the slope and it will no longer cut exactly. The problem can be solved only by replacing the tire.

    The inability to make a straight cut with a tool is a sign of increased tire and chain wear, which in turn is worth looking for its cause. Eliminating the effects of wear by replacing consumables will not bring the desired result, because in case of not eliminated malfunctions of the lubrication system, after a while everything will be repeated.

    How to assemble

    After all repair work has been completed, the quality of the reassembly is of great importance. Incorrect positioning of the part can lead to equipment damage and be unsafe for humans.

    • The most critical part is assembling the saw headset. It is better to make it with protective gloves to avoid cuts from stars. When installing the chain on the bar, pay attention to the direction of the teeth edge. It should go forward on top of the tire. Place the mechanism on the drive sprocket. Return the clutch cover, tighten the nuts.
    • Use a special wrench to tension the chain. The quality of this work affects the safety and efficiency of equipment operation in the future. A poorly tensioned chain will fly off, and tight tension threatens to wear quickly. The chain can be lifted no more than 1 cm above the bar.Check the rotation and tighten the nuts.

    Any repair work on complex equipment should be carried out carefully. It is better to use original spare parts for this. Other options can negatively affect the life of the device. If you are not sure if you can do it yourself, it is better to contact a specialized workshop.

    This is especially applicable for expensive professional equipment. Improper repairs can lead to failure of the entire mechanism. To prevent breakdowns, try to follow the requirements of the instructions for work, service the tool in time, watch the mechanisms, use high-quality oil and fuel, replace wear parts.

    Even professional chainsaws from world famous manufacturers break down. no one is immune from this. The question is how often breakdowns occur and how serious they are. It is one thing to sharpen the chain or replace the drive sprocket, and another thing if the chainsaw does not start or fires at the carburetor. In fact, most of the malfunctions can be easily eliminated with your own hands, for example, when the chainsaw does not lubricate the chain or stalls.