The chainsaw starts and stalls Reasons why the chainsaw starts and stalls immediately, does not develop speed and does not give maximum power, and their elimination
Why does the chainsaw start and immediately stall
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 operation 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. A strong air leak 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, melting of the piston, jamming of the crankshaft.
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.
A saw that is unable to operate under load will also be unsteady at idling. They will swim. 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 is detected in the carburetor, the cause can be eliminated by installing a repair kit of gaskets.
Only after the above actions have not yielded results and the engine crankcase with the carburetor is sealed, you can start adjusting 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 operate at all under load.
, which shows how to replace a defective impulse hose with your own hands on a HUSQVARNA 142 chainsaw, can be seen below. In it step by step the process of disassembling the saw is filmed, the impulse hose is shown and the consequences of its malfunctioning HUSQVARNA 142 are discussed.
Malfunctions leading to improper operation of the chainsaw
There are a number of faults that must be taken into account when diagnosing, since they can lead to interruptions in the operation of the saw.
- Worn crankshaft bearings. With worn out crankshaft bearings, runout is inevitable on the main shaft, where the flywheel is attached. In such a situation, it is impossible to adjust the gap between the flywheel and the ignition coil, which entails interruptions in sparking, and unstable operation of the chainsaw.
- Impulse channel contamination. The impulse channel serves to ensure the operation of the fuel pump, respectively, its contamination leads to improper operation of the pump, which will make it impossible for the saw to work (it will start and immediately stall).
- CPG wear. As a rule, with increased wear of the CPG, there is a decrease in compression in the engine of the chainsaw, which will necessarily affect its ability to develop speed.
- Dirty fuel and air filters.
The chainsaw starts and stalls. Why?
There are several simple rules for the operation and maintenance of a chainsaw, the observance of which will allow you to maximize its service life. Preparing the correct fuel mixture, regularly cleaning filters and periodically replacing parts will save you from having to repair your tool for a long time. If it was not possible to avoid the breakdown, then you can figure out its cause completely independently. This applies to all brands of chainsaws, from the more complex Husqvarna and Stihl models to the simplest Makita and Patriot models.
The chainsaw stalls immediately
What to do if the chainsaw stalls immediately after starting? First you need to check the presence of fuel in the gas tank. If its level is not enough, then you need to prepare the fuel mixture in strict accordance with the ratio of gasoline and oil prescribed in the operating instructions. Gasoline must have the highest possible octane number, and the required brand of oil, as a rule, is indicated in the data sheet of the chainsaw.
Next, we check the spark plug, as well as the contact of its tip with the high-voltage wire. The gap between them should be no more than 0.5 mm. If necessary, the candle is cleaned of carbon deposits and dried. It is recommended to occasionally change the candle to a completely new one. The reasons for the tool stalling when you press the gas lie in the fuel filter or carburetor jet. Cleaning the gas filter will not take much time and effort, but it is better to entrust the disassembly and cleaning of the carburetor to the specialists of the service center.
Chainsaw stalls at idle speed
Cases are common when the chainsaw stalls at idle. First of all, you need to check the muffler, and, in case of contamination, clean it from exhaust tar deposits. Also on the carburetors of some models, etc., there are bolts with the inscriptions H and L, respectively, rough and fine tuning. By adjusting the bolt L during the operation of the chainsaw so that its speed increases (turn the bolt just half a turn), it is possible to eliminate this problem. Adjusting the carburetor requires an electronic tachometer and is a rather time consuming process. That is why, in such cases, it is better to turn to professionals.
After starting, the engine immediately stalls: why is this happening
During the operation of the car, a frequent situation is that after turning the ignition key, the car starts, the engine starts to work and stalls after a few seconds. As a rule, 3-5 seconds pass from the moment of starting to stopping the internal combustion engine. Before the engine stops completely, engine vibrations are also noticeable, the power unit shakes, it works very unstable.
This happens as a result of a decrease in speed, resonance effects of a rotating crankshaft, etc. If you try to start the engine again, the motor may no longer start, or the situation described above may happen again.
The reasons for this problem are different. The main thing is that if the car starts up and stalls, this indicates that in-depth diagnostics are needed. Next, we will talk about what to do in such a situation, as well as how to find the reason why the engine stalls after starting.
Engine Starts and Stops: Troubleshooting
So, if a similar problem manifests itself, then it is necessary to take into account a number of features. First of all, the following factors will affect the operation of the internal combustion engine after launch:
- Fuel supply;
- Air supply;
- Spark on spark plugs (for gasoline internal combustion engines);
- Correct operation of glow plugs (for diesel engines);
- Proper operation of the ECM and electronic sensors;
With that said, the first place to start is by checking the main possible causes:
- Quite often, malfunctions in the alarm and anti-theft complex can cause the engine to fail after starting. In other words, the immobilizer does not turn off and continues to block the start of the internal combustion engine, which is its main function to prevent theft of the vehicle. If the alarm blocks the engine, then it is necessary to check the operation of all elements, try to reset the error, turn off the anti-theft system, etc.
- Problems with the IAC and the idle valve often arise due to contamination of these elements. You should also pay attention to the cleanliness of the throttle valve. As for the crankshaft sensor, incorrect data that it transmits to the ECU can cause the engine to stop immediately after starting.
- Poor quality of fuel and lubricants can also cause malfunctions. As a rule, problems begin in cases when low-grade fuel was filled or the engine uses inappropriate / deteriorated engine oil.
- A faulty fuel pump, air leakage in the fuel line, the formation of air jams and contamination of the fuel filters do not allow creating the required pressure in the power system or supplying fuel in the required volume.
- The air filter and its contamination leads to the fact that the working mixture is significantly enriched. In other words, there is not enough air for the engine to burn fuel, the spark plugs are flooded.
- Problems with ECM sensors (EGR sensor, oxygen sensor, DPKV, etc.) can lead to both unstable engine operation at idle and a complete engine stop after starting.
Now let’s dwell on the most common problems and how to fix them, looking at them in detail.
- First of all, the culprit may be the low level of fuel in the gas tank and its quality. If gasoline or diesel fuel runs out, then the engine will start on the remains in the power system, but its further operation will be impossible.
Water is heavier than gasoline and sinks to the bottom. If this is the case, then the problem has been detected. To solve it, it will often be enough to dilute the existing fuel with high-quality fuel, after which the engine can usually be started.
However, this does not always work. Cases are not excluded when the supply of low-quality fuel available in the tank will need to be completely drained, after which a thorough cleaning and flushing of the power system is performed.
If the malfunction manifests itself on a diesel engine, then fuel problems can lead to more serious consequences. For example, if a diesel engine starts up and stalls in winter, then paraffinized and frozen diesel fuel may be the cause. In this case, diesel fuel must be warmed up, filters cleaned, etc.
It is much worse if gasoline accidentally gets into the tank of a diesel car. In such a situation, there is a high risk of serious damage and failure of the expensive fuel equipment of a diesel engine (injection pump, injectors).
- The next reason that the engine starts, runs and stalls may be the battery. The fact is that many systems and actuators need a sufficient battery charge for normal operation.
- Another element worth paying attention to in the event of a sudden stop of the internal combustion engine after starting is the fuel pump. On modern injection cars, the fuel pump is located in the fuel tank.
In order to check its operation, you must turn the key in the lock, turn on the ignition and listen carefully. In the first seconds after turning the key, a characteristic slight hum-buzz should be heard. This sound lasts for a few seconds, indicating that the fuel pump has started working and is creating pressure in the fuel system.
If such a sound is not heard, then it is necessary to determine the reason why the gasoline pump does not pump gasoline. The pump motor itself, the fuel pump relay, fuses and other elements of the electrical circuit can fail. We also add that the ECU can turn off the power to the pump if the crankshaft sensor does not give a signal.
It is also important to take into account that the filter mesh on the gas pump can become clogged. For accurate diagnostics, it is advisable to measure the fuel pressure in the fuel rail using a pressure gauge.
Another common cause can be a fuel filter. If it is dirty, then a decrease in throughput leads to the fact that the pump cannot pump gasoline in the proper volume for normal engine operation. As a result, the unit stalls after starting.
- If there is fuel in the system and the pressure is normal, then the problem may be related to the ignition system. Most often, candles and candle high-voltage wires fail. For wires, it is common for the engine to stall after washing or in wet weather.
One way or another, it is necessary to unscrew the candles, clean the elements, check them for a spark. If the spark plugs have not changed for a long time, then it is better to immediately install a new kit. As for the armored wires, they also need to be checked for operability and replaced if necessary. In parallel, on some cars, you need to check the ignition timing.
- Synchronous operation of the valve train can be disrupted due to the fact that the timing belt or chain may be incorrectly installed, stretch, wear out and can jump on the pulleys. As a result, the opening and closing of the intake and exhaust valves does not match the engine strokes.
In this case, to eliminate the problem, it is necessary to check the specified elements, set the timing belt according to the marks and perform other necessary procedures.
- ECU malfunctions are less common, but this possibility should also not be ruled out. Additional attention is deserved by cases when the controller was flashed, chip tuning was performed, or HBO was installed on the car.
You can do the specified diagnostics yourself. To do this, you need an adapter to the OBD2 diagnostic connector, which will allow you to read error codes and display the information received on the screen of a tablet, laptop or smartphone.
What is the result
As you can see, there are many reasons why the engine starts to work and stalls after starting. However, most of them are usually associated with the fuel system, ignition system and electronic control system.
In this case, it is appropriate to talk about low compression on the cylinders due to the fact that the engine has exhausted its resource (cylinder walls, rings, etc. Are worn out), that is, the unit needs major repairs. Compression can be measured at the workshop or by yourself using a compression meter.
The engine stalls at idle: what to check. Possible causes of malfunction on engines with a carburetor, injector, diesel power plants.
The idling speed is floating: why is this happening. The main malfunctions associated with idling on a gasoline and diesel engine.
The main reasons why the engine starts to stall after warming up. Frequent problems of carburetor and injection engines, fault diagnosis.
Why the engine may not pick up speed: a gasoline engine, a diesel unit, a car with LPG. Fault diagnosis, useful tips.
The reasons why, after pressing the gas pedal, failures occur and the engine begins to swell. Engine failures with LPG when switching from petrol to gas.
Reasons why the engine can stall when you press the brake. The power unit stalls during sudden braking, when the clutch and brake are pressed, etc.
At high revs
When the scythe stalls at high speeds, this is due to the following problems:
- Clogging or sticking of the valve located on the gas tank cap;
- The carburetor is out of alignment under the influence of vibrations arising during the operation of the mechanism;
- Problems with the circulation of the fuel mixture;
- Suction of atmospheric air;
- The fuel intake hose is cracked or loose.
Adjust the carburetor according to the trimmer operating instructions. For adjustment, it is often sufficient to loosen the tightening of its housing. If there are problematic points with the circulation of the fuel mixture, then it can gradually enter the carburetor. After its development, the engine stalls at high speeds.
The lawn mower often stops when it heats up. At the same time, it starts, works with jerks and gradually stops. This process occurs when the gasoline in the carburetor boils or the damper is installed in a rotary rather than disc type. In the latter case, the part is changed.
It happens that the trimmer heats up if the ignition circuit wire or coil is damaged. In order for the device to start working normally, parts are replaced.
When you press the gas
If the lawn mower stops when the throttle is pressed, the reasons may be as follows.
- The most common variant is carburetor adjustment failure, which occurs when the drive is under significant stress, after prolonged inactivity of the mechanism, or when it is used in difficult conditions.
- Clogging of the fuel valve, which is eliminated by loosening it, as a result of which gasoline begins to flow normally through the system.
- Loosening and drooping of the cable in the carburetor. The fuel hose can also be stretched to the point of rupture due to significant stress.
- Clogged breather (non-return valve), as a result of which fuel does not flow into the tank.
If the problem is related to the carburetor unit, then it can be recognized by the appearance of vibrations of the lawn mower.. When the hose bursts or the cable is stretched, these components are replaced.
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 may be the low fuel level in the tank. This can be confirmed by stopping the operation of the tool when tilting, when fuel remains 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 which case it is necessary to completely replace it.
- Clogged breather, 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 degradation 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 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 revolutions.
- Chain shortage due to lack of or insufficient lubrication, or a problem with the chain brake.
Why the chainsaw does not start well and stalls
With a poor start of the equipment to a cold, the problem may be the lack of compression, i.E. 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 flow of air, leading to an increase in saw speed.
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
- The engine starts and stalls
- Unstable tool performance
- Work 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
- Carburetor clogged
- High voltage wire problems
- Lack of compression.