Why Chainsaw Stalls: Causes And Solutions

If the chainsaw stumbles and starts to stall, the performance of the simplest sawing operations is out of the question. Not only budget-grade tools but also quite prestigious models from leading manufacturers are subject to inevitable failures.

The reason for stopping the chainsaw in full swing can be:

  • poor quality of parts and entire assemblies;
  • unqualified care;
  • the use of low-quality fuel and oil substitutes;
  • illiterate exploitation.

The remoteness from the service departments and the high cost of the provided repair services force the owners of the failed tools to restore their working capacity on their own.
This option is possible only after the expiration of the warranty. The difficulty lies in the fact that the traces of the dismantling of individual components and assemblies seen by service specialists can be the cause of the refusal of free repair of more complex and expensive parts.

The advantages of self-repair.

Experts offer several search options. causes of poor engine start or if the power unit stalls during operation. The recommendations are equally valid for household and professional class chainsaws.
Owners with operating experience of the petrol-sawing machinery use simple, time-tested intuitive troubleshooting algorithms, which allows resolving many failures and breakdowns directly in the process quickly.
The success of the work contributes to the knowledge of the design of the tool and the interaction of all its components, the availability of repair and maintenance skills and operational experience. These abilities allow owners to use their chainsaw technology with high efficiency.
Self-repair provides the ability to save material resources and reduce downtime significantly.

Determining the nature of the fault.

The main part of the failure of chainsaws of any class accounted for fuel equipment. For the ignition system, this figure is an order of magnitude less. Stopping chainsaws due to mechanical failures in the practice of household and professional sawing is even less common.

Electrical equipment.

Malfunctions of the ignition system are determined simply by checking the spark for a spark and adjusting the gap in the contacts. After verifying the integrity of the wiring causes of failure should be sought in the work of the electronic unit.
The absence of a spark on the contacts can be a consequence of the breakdown of the suppressor resistor located in the housing of the candlestick. To check its integrity, it is sufficient to connect the high-voltage wire directly to the candle.

Mechanical failure.

A sudden stop of a chainsaw can be caused by a piston jamming in the cylinder or the destruction of the crankshaft bearing due to oil starvation or poor quality of engine oil.
In the first case, the serviceability of the tool can be restored by pouring a few drops of engine oil into the plug hole. Elimination of damage to the crank mechanism provides for complete disassembly in a well-equipped workshop.

Elimination of fuel equipment failures.

A simple analysis of failures and faults shows that more than half of them fall on unqualified fuel system tuning. Upon closer examination, it turns out that the reasons for the situation when the engine does not start, is not gaining momentum and stalling is almost the same.

In most cases this is:

  • air leaks due to the weakening of screw fasteners or the destruction of the crankshaft packing;
  • jet contamination;
  • float valve leaks;
  • wear of the booster pump seal.

Signs of characteristic failures.

If the saw engine is not gaining momentum and stalling, does not develop power and stalls under load, most likely there is a shortage of fuel or incorrect adjustment of the carburetor.
The list of possible causes. a pollution of the fuel filter or filter element of the air intake, too rich or poor gasoline-air mixture, etc.

Signs of a rich engine operation:

  • slower speed;
  • smoke from the muffler;
  • reduction of traction and fuel consumption.

Chainsaw stalls when you press the gas. most likely the mixture is too poor.

A simple way to determine the quality of the mixture.

The easiest and most affordable way to check the quality of the mixture is the central insulator of the spark plug. Brown color of any intensity indicates the correct adjustment of the carburetor.
The consequence of working on a rich mixture is the formation of a black deposit on the insulator, a weak mix. it manifests itself as a pure insulator of a white or light gray colour.
If after a normal start-up and warm-up, the saw-fueled 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 can be condensate water that has entered the carburetor float chamber.

Engine shutdown during operation.

In another embodiment, if the chainsaw heats up and stalls, troubleshooting should be sought in the settings of the carburetor or the high-voltage circuit of the ignition system unit.
When it overheats, the spark disappears or becomes so weak that its power is not enough to fully ignite the air-fuel mixture.
The engine also stalls for hot when malfunctioning of the damping resistance fails, which locates at the tip of the spark plug.

The engine stalls when switching to idle.

The fault is manifested by unstable work in the working mode and stalls at idle. The reason for this phenomenon, most likely in the air suction between the carburetor and the suction inlet pipe of the cylinder. Failure eliminates by tightening the screw fastener.

The engine of the chainsaw shuts down after reaching the maximum speed mode.

The power unit stalls at high speeds due to the non-compliance with the stated requirements of the electronic unit performance. Failure is more characteristic of budget chainsaws made in China.

The reason for refusal may be:

  • lack of fuel mixture in the float chamber due to valve sticking;
  • a clogged fuel filter or a breather in the fuel tank cap.

The power unit also stalls at high speeds due to a dirty air intake filter. The same signs are typical for the situation when the chainsaw started up in a standard mode and stalled during the warm-up phase.

Fuel system tuning.

Qualified carburetor adjustment allows you to bring the power unit to a combination of maximum traction parameters and economical fuel consumption.
The success of the work is facilitated by pre-cleaning the air intake filter, warming up the engine to operating temperature, making adjustments in the sequence specified in the instruction.

The result of the correct setting of the carburetor is:

  • a quick set of revolutions without a “failure” characteristic of a poor mixture during the sharp giving of gas;
  • no increased smoke from the muffler;
  • stable idle speed.

Non-standard failures.

If a normally working engine of the chainsaw stalls when the tool is tilted to one of the sides, you should open the gas tank cover and remove the hang of the flexible fuel receiver.
Virtually the entire range of Chinese chainsaws is more or less copied from popular models of European origin, so the structural differences are minor. The above recommendations can be used if the Chinese chainsaw failed.
The maintainability of the Chinese chainsaw technology is enhanced by the unification of the repair stock and the interchangeability of many components and parts with the same type of models.