Chainsaw Stalls At Idle Cause

Why does a chainsaw engine stall when you press the gas

Despite the high performance of chainsaws, sometimes there are moments when the tool stops working normally. In particular, a common situation is the fact that the chainsaw starts to stall when you press the gas. For experienced tool owners, this problem is known, but beginners who are faced with this for the first time will have to seek help from specialists. But do not rush, in the material you can find all the important causes of the malfunction, as well as try to eliminate them.

Chainsaw Stalls At Idle Cause

Stalls when you press the gas

If the engine stalls when gas is added, this may be due to:

  • Clogged or improper carburetor setting;
  • Dirty air filter, whereby the engine does not have enough air to set speed;
  • Clogged fuel filter, which contributes to the intake of an insufficient amount of fuel mixture;
  • Malfunction of the cylinder-piston group. With an insufficient amount of oil in the fuel mixture, excessive friction of the piston against the cylinder walls occurs, which leads to overheating and the formation of scoring.

In case of overheating with a lack of oil in the fuel mixture, it will be necessary to overhaul the engine, which is one of the most unpleasant consequences. In order to properly adjust or clean the carburetor, you should give it to a specialist, as lack of experience with small parts can damage the mechanism. Do-it-yourself air and fuel filter check.

It’s important to know! The fuel filter should be replaced every 3 months during daily use of the tool.

If the chainsaw does not allow you to develop speed when you press the gas, then it is advisable to try to replace the fuel mixture in the tank, especially if it has been in the tool for a long time.

Check filters

In the event that the saw does not receive enough air or fuel, naturally, it will stall when trying to increase the speed or even just at idle speed. The filter contamination is checked purely visually. Filters need to be changed if dirt problems are suspected.

What to do if the chainsaw stalls when you press the gas

One of the most common questions regarding the operation of this device: why does the chainsaw stall when you press the gas and what should be done to solve this problem? In such a situation, you need to do the following:

  • Check the fuel filter;
  • Inspect the fuel hoses for tightness;
  • Check the muffler;
  • Try to speed up a little;
  • Check the condition of the rubber seals on the crankshaft.

Clogged muffler

Over time, the muffler can become clogged. This occurs as a result of using a fuel mixture with too much oil. Deposits in the muffler impede the free flow of gases, resulting in reduced engine power. This malfunction can be determined by the gradual manifestation of the problem, as well as by the soot on the muffler.

Stalls under load

If the chainsaw starts to stall under load, then the reason for this is, first of all, an incorrect carburetor setting. If this reason is eliminated, then in addition to problems with the carburetor, the reason for the inoperability of the tool under load may be damage and wear of the crankshaft oil seals or carburetor gaskets, through which air is sucked into the system.

It’s important to know! It is better to diagnose such a malfunction in a service center, where the exact cause will be established.

It is recommended to start troubleshooting by checking the oil seals and gaskets, and after that check the correctness of the carburetor setting. Another reason why the chainsaw starts up and immediately stalls under load may be the chafing of special hoses, through which impulse is transmitted from the crankcase to the fuel pump. But such hoses are not installed on all models of chainsaws, but only mainly on professional ones. Replacing this hose is recommended to correct the problem. How to do it correctly is discussed in the:

Why the chainsaw does not start well and stalls

With a poor start of the equipment "to cold" the problem may be in the absence of compression, ie. The rings are worn out due to a long service life, they need to be replaced. Sometimes the reason that the engine does not start well in an unheated state is a problem with the muffler, as well as poor contact between the plug and the wire.

Also, the reasons for a poor start can be wear or damage to the gasket, rubber cuff in the accelerator pump of the carburetor, which causes an additional air flow, leading to an increase in saw speed.

The chainsaw starts and stalls: the reason,

The reason that the chainsaw can stall right after the factory lies in the malfunction of a certain part of the equipment.

  • The most commonplace reason why the chainsaw started up and stalled could be the low fuel level in the tank. This can be confirmed by stopping the operation of the tool when tilting, when fuel residues accumulate in a certain place in the fuel tank. With low-quality fuel, there may also be a problem with the operation of the chainsaw, in this case, you need to completely replace it.
  • Breather blockage, which significantly reduces fuel consumption to the engine.
  • Insufficient contact of the wire cap with the plug, which leads to strong heating of the plug insulator. Contact deterioration can occur due to mechanical shear or carbon deposits.
  • Broken spark plugs.
  • Clogged muffler, which impairs exhaust gas output, causing the engine to stop running. For this reason, the chainsaw can start and stall at idle speed. Sediment in the muffler can also appear due to poor-quality fuel or improper use of the tool.
  • Poor carburetor adjustment.
  • Breakage of the piston group
  • Fuel filter or pump problems. In this case, gasoline may flow through the pump or poorly flow through the fuel filter to the carburetor. As a result, the chainsaw starts up and stalls when the speed increases.
  • Dirty air filter. Problems with this piece of equipment lead to the fact that, with increased loads on the engine, it simply cannot cope with them due to blockage and stops. A similar result is also obtained with an increase in speed.
  • Short circuit due to lack of or insufficient lubrication, or a problem with the chain brake.

The reasons why the chainsaw starts and stalls

A chainsaw has long been not a luxury, but a necessary tool for those who have a summer cottage or home ownership. But, like any other technique, this tool tends to fail, despite the simple device.

The classification of the main faults includes:

  • Complete absence of engine plant
  • Engine starts and stalls
  • Unstable tool performance
  • Stop under load
  • Loss of power.

If the chainsaw does not start at all, the reason may be:

  • Manufacturing defect
  • Lack of fuel
  • Problems with starting the ignition system
  • No spark from spark plugs
  • Poor fuel mixture
  • Carburettor clogged
  • High voltage wire problems
  • No compression.

Why does the chainsaw start and stall, what to do in this case? The reasons for this need to be considered in detail.


The operation of the equipment must be correct, with periodic inspection of the constituent elements to prevent damage. To troubleshoot, it is necessary to check all components of the equipment for their functioning.

If the chainsaw starts and stalls, the cause can be eliminated on your own. If it is a shortage or improperly prepared fuel mixture, it must be corrected. For prophylaxis during the idle time of the chainsaw, you should always drain the remaining fuel.

Spark plugs should be checked periodically. In this case, remove carbon deposits that clog the joint gap, and also check the tips for the presence of fuel. Another cause of spark plug problems can be gasoline getting wet. To do this, they need to be removed, wiped off with a rag and left to dry. Defective spark plugs are replaced.

If there is no spark between the spark plug and the high-voltage wire, but if there is a good connection, the ignition unit must be replaced.

A clogged muffler is a common cause of breakdown, in which the chainsaw starts up and immediately stalls. To eliminate the malfunction, you need to dismantle the muffler, clean it from carbon deposits using sandpaper or a special chemical solution. If the model of the chainsaw is non-separable, chemicals are poured into the system and are there for several hours, then it is blown.

The carburetor must be adjusted if the chainsaw stalls at idle speed. Fine tuning is a rather laborious process, so it is usually done in service centers. But, on some models there are elements for adjusting it, it is enough to turn the bolt half a turn to increase the speed of the chainsaw, the problems will be eliminated. If the jets, nozzles, channels and filters are clogged, the entire carburetor must be disassembled and cleaned. When oil seals, gaskets, cuffs are worn out, it is necessary to replace them, preventing air leakage.

If there is a problem with the fuel or air filter, replace the fuel pump or clean the air filter.

If the breather is clogged, it must be cleaned with a regular needle.

When the chainsaw starts up and immediately stalls, the reason may lie in the malfunctioning of the chain. To troubleshoot problems, check the presence of oil in the chain lubrication container, as well as the oil return pipe for breaks or blockages.

When inspecting the piston group, pay attention to the cylinder; if necessary, replace it or the piston. The cylinder can be bored to fit the new piston. If the piston with the cylinder is normal, you should pay attention to the defects of the piston rings and the need to replace them.

Among other things, you should monitor the service life of the parts specified in the product passport, which include the drive sprocket, tire, chain, part of the anti-vibration system, and replace them in time.

If the tool is idle for a long time, it is worth checking the condition of the fuel line. If the tube is cracked, you will have to replace it with a new one.

Why stalls at idle

The first and most common cause of this malfunction is improper carburetor adjustment. You can adjust the idle speed yourself, for this you need to have a Stihl adjusting screwdriver, which is supplied with the unit. The adjustment hole is located on the right side of the Stihl 180 saw on the handle and is marked with "-" and "".

If the Stihl chainsaw does not keep revving and stalls at idle, you can be almost 90% sure that it has irregularities in the fuel pump operation system, as a rule, it is air leaks into the crankcase through the oil pan gasket, or, much more often, through the oil seals crankshaft. Air leaks reduce or completely stop the impulse that is fed through special channels to the fuel pump of the chainsaw. As a result, the Stihl 180 chainsaw does not receive the required amount of fuel and stalls at idle.

Diagnostics can be carried out using a special device called a vacuum gauge.

The second way to check the performance of the oil seals is to pour gasoline into the crankcase and look at them, if the oil seals let gasoline pass, then they cannot provide normal pressure in the crankcase, which will make idle work impossible. And when operating at high speeds, with leaking oil seals, there is a possibility of seizure of the crankshaft bearings.

The algorithm for checking the crankcase and Stihl 180 oil seals for leaks is as follows:

  • Removable top cover.
  • Dismantle the air filter housing and carburetor.
  • The handle of the chainsaw is removed.
  • The starter spins and retracts.
  • On the opposite side from the starter, the side cover and the drive sprocket are removed.
  • A piston stopper is installed in the spark plug hole or a string from the old starter with knots imposed on it is stuffed into the cylinder.
  • The flywheel and clutch are unscrewed, after which the parts are removed. It is worth knowing that the chainsaw clutch has a left-hand thread and unscrews clockwise.
  • The gear wheel of the drive of the oil pump is removed.

Having disassembled the Stihl MS 180 chainsaw, you can see the oil seals, then you need to fill the crankcase with gasoline and check the leakage. The crankcase can be filled through the fuel window in the cylinder; for this, the piston must be raised as high as possible. If leaks are found, it is necessary to replace the defective oil seals, or re-seal the pallet. You can assemble Stihl 180 by following the reverse sequence of the algorithm.

Why does the chainsaw stall when you press the gas

Let’s say the chainsaw works normally at idle, but when the gas is pressed sharply, it stalls. What is the reason perhaps? It is immediately clear that the matter is not in the ignition (no spark), since if the ignition is faulty and there is no spark, the tool would simply not start. Means the fuel system remains.

There are many defects in the fuel accounting system to determine a clear prerequisite, because of which the Stihl 180 chainsaw stalls when you press the gas, you need to carry out its full diagnostics. We advise you to read about the common malfunctions of the Stihl 180 chainsaw and the elimination of these defects.

Filter check

The first thing to check is the fuel filter.

In some cases, a filter that is clogged with dirt is unable to pass enough fuel mixture through it. Accordingly, a fuel shortage arises in the system, which leads to the fact that when you press the gas of the chainsaw, the fuel burns out, and the new one does not have time to enter, as a result of which the Stihl chainsaw stalls. Also, with a clogged fuel filter, there may be a noticeable drop in the power of the chainsaw at maximum speed, but this is with slight contamination.

Filter check

The first thing to check is the fuel filter.

Sometimes, a filter clogged with dirt is unable to pass the fuel mixture through itself in sufficient quantities. Accordingly, a lack of fuel appears in the system, which leads to the fact that when you press the gas of the chainsaw, the fuel burns out, and the new one does not have time to flow under the influence of which the Stihl chainsaw stalls. Also, with a clogged fuel filter, there may be a noticeable drop in the power of the chainsaw at the highest speeds, but this is with insignificant pollution.