In detail: DIY chainsaw repair from a real master for the site my.housecope.com.
The chainsaw is a worthy replacement for hand saws and axes. Today, this tool is available in almost every household - it is indispensable for setting up a personal plot, construction and repair work. Intensive use and improper care of the tool can lead to premature failure. However, the owner of the chainsaw does not have to go to the workshop right away - many of the faults that can happen to her during operation can be completely eliminated on their own.
6 Checking the carburetor and signs of need for adjustment
7 Calibration algorithm and safety precautions when troubleshooting the chainsaw carburetor
8 Other chainsaw malfunctions
9 DIY chainsaw repair, video
Correct diagnosis is essential for a successful repair. Therefore, in order to determine why the chainsaw failed and, most importantly, how to make it work again, you first need to know the features of its design.
It should be noted that it does not differ in particular complexity, since it includes:
engine (two-stroke gasoline);
functional part (saw bar and chain);
systems that ensure the joint operation of these two units (ignition, filtration, lubrication, etc.), that is, the tool as a whole.
In order to simplify the diagnosis of malfunctions, it is customary to distinguish them into two main categories:
engine malfunctions;
malfunctions of other parts of the chainsaw.
Most often, failures occur in the engine systems, however, the rest of the tool, due to intensive use or improper care, can fail at any time. How to determine exactly where the breakdown occurred? Simple logic will help us with this.
Video (click to play).
If the problem is in the engine, it will:
do not start;
deafen;
work unstable;
overheat;
smoke;
develop insufficient power.
As for all other malfunctions, as a rule, they manifest themselves with a normally operating motor.
If your chainsaw won't start, the first thing to do is to check for a mixture of fuel in the tank. By the way, it must be prepared in the proportions indicated by the engine manufacturer, otherwise the instrument will simply not start.
After verifying that the fuel mixture is correct and available, the ignition system should be checked. To do this, you need to inspect the spark plug.
Her condition can say a lot:
indicates that the fuel mixture does not enter the carburetor, which means that the problem is not in the ignition;
fuel-splattered candle
is the result of an overabundance of the fuel mixture, which lies either in a violation of the engine starting algorithm, or in an incorrect carburetor adjustment;
this is a signal about the presence of low-quality oil in the engine lubrication system, incorrect carburetor settings, or an incorrectly prepared fuel mixture.
If the spark plug is splashed with fuel, wipe it thoroughly after removing it. The fuel supply system should also be cleaned. To do this, it overlaps, after which the starter is turned on. A carbonized candle must be carefully cleaned with an awl and emery.
When checking the spark plugs, you should pay attention to the distance between the electrodes (the normal gap is 0.5-0.65 mm), as well as the condition of the gasket and the presence of a spark. A damaged or worn gasket will have to be replaced, and the spark can be checked by putting on the ignition cable, connecting the cylinder and plug nut, and starting the starter.
If the discharge does not occur, the plug must be replaced. In the event that a spark does not appear with a new candle, then the problem is in the connection to the high-voltage wire or in it itself.
If the fuel mixture does not flow into the cylinder, but the spark plug is working properly, this may mean that:
Clogged fuel filter.
To clean this unit, remove the fuel hose and check the jet. If it is weak, the filter must be removed through the filler hole of the fuel tank and cleaned or replaced if completely worn out.
As a preventive measure, it is recommended to replace the fuel filter at least once every 3 months.
This is nothing more than a hole in the fuel tank cap, which is cleaned out with an awl.
The fuel mixture is not supplied or is supplied insufficiently.
There may be several reasons for this:
the air filter is clogged (in this case, it must be removed, rinsed with water, dried and replaced);
the carburetor settings are out of order (which means this unit needs to be re-adjusted);
the integrity of the carburetor membrane is broken (must be replaced);
the channels of the carburetor are clogged (it must be disassembled and all parts and assemblies must be cleaned).
If at low speeds the engine of the chainsaw works normally, but at high speeds it starts to stall and smoke, the problem may be hidden in the muffler.
To check the quality of its work, you should do:
dismantling (with the obligatory closing of the outlet);
disassembly (if the muffler is collapsible);
cleaning from carbon deposits using special detergents or dry method;
drying (using a hair dryer);
reassembly and assembly.
Dry cleaning without respiratory protection is not recommended. The carcinogens present in the soot will be released into the surrounding atmosphere in the form of dust, the inhalation of which is extremely hazardous to health.
To prevent clogging of the muffler during the operation of the chainsaw, you should carefully monitor the composition of the fuel mixture and the quality of its components.
If the chainsaw engine does not start or cannot develop normal power, it is likely that sufficient pressure does not build up in the engine cylinder for combustion of the fuel mixture. The reason for this may be the wear of the elements of the cylinder-piston group - the piston, rings, bearings, etc. In order to assess the condition of this unit, it should be visually inspected, having previously removed the muffler.
For a more complete diagnosis, a compression gauge is placed in the spark plug hole of the two-stroke engine of the chainsaw. It measures the compression in the engine. Based on the results of the check, one can judge the state of the CPG, however, the exact facts can only be obtained with a complete disassembly of the unit.
If the piston is chipped or scratched, it will obviously need to be replaced. The same applies to deformed or broken piston rings - for normal engine operation, they must be completely intact and free of carbon deposits.
A properly working carburetor guarantees maximum efficiency of the chainsaw, that is, it is possible to develop full power with the most economical consumption of the fuel mixture. The adjustment of this unit is usually carried out by the manufacturer, but its design provides for the possibility of adjustment already during operation.
The fact that such a setting will have to be performed by the owner of the chainsaw is evidenced by:
Strong vibrations or damage to the protective cover.
CPG wear.
Carburettor clogged.
Inability to start the engine or its spontaneous stops after starting.
Increase in fuel consumption and emissions while decreasing engine power.
Chainsaw carburetor adjustment is carried out in strict accordance with the manufacturer's instructions using three special screws, which are responsible for the maximum ("M") and minimum ("L") revolutions, as well as the idle speed of the engine ("T"). In order to exclude unwanted interference by an inexperienced user with the carburetor operation, some manufacturers install only one idle screw.
Carburetor adjustment is carried out in two stages:
Basic (carried out with the engine off).
Finishing (carried out with a running, pre-warmed engine).
For basic adjustment, screw in screws H and L as far as the stop and back out 1.5 turns. Final adjustments require the engine to warm up for 5-10 minutes at low revs.
The final calibration is performed by unscrewing the idle screw until the minimum engine speed is reached (in this case, its operation must be stable, and the chain must be stationary). If the engine stops at idle speed, the screw must be returned back, and if the saw chain is still in motion, continue turning counterclockwise.
Calibration check is performed by test:
Acceleration (with a smooth press on the accelerator, the engine should quickly pick up speed to the maximum indicator).
Maximum speed (if there is an ignition interruption, screw H should be slightly loosened).
Work at idle speed (the chain should not move, and the engine should pick up speed as quickly as possible).
If the owner of the chainsaw is not familiar with the carburetor device and does not have the tool necessary to calibrate it, contact a specialist. The carburetor is a very complex unit, so any wrong action can lead to irreversible consequences, for example, complete engine failure.
If the diagnostics showed that everything is in order with the engine and its systems, then the cause of the malfunction should be looked for in other units of the chainsaw. The most common problems are:
failure of the starter;
improper operation of the lubrication system;
incorrect operation of the chain brake;
saw chain wear, etc.
If the cause of the tool failure is not visible to the naked eye, as is the case with the engine, it is necessary to perform a thorough diagnosis of the faults and eliminate them in accordance with the manufacturer's recommendations and safety regulations.
The chainsaw is a worthy replacement for hand saws and axes. Today, this tool is available in almost every household - it is indispensable for setting up a personal plot, construction and repair work. Intensive use and improper care of the tool can lead to premature failure. However, the owner of the chainsaw does not have to go to the workshop right away - many of the faults that can happen to her during operation can be completely eliminated on their own.
Correct diagnosis is essential for a successful repair. Therefore, in order to determine why the chainsaw failed and, most importantly, how to make it work again, you first need to know the features of its design.
It should be noted that it does not differ in particular complexity, since it includes:
engine (two-stroke gasoline);
functional part (saw bar and chain);
systems that ensure the joint operation of these two units (ignition, filtration, lubrication, etc.), that is, the tool as a whole.
In order to simplify the diagnosis of malfunctions, it is customary to distinguish them into two main categories:
engine malfunctions;
malfunctions of other parts of the chainsaw.
Most often, failures occur in the engine systems, however, the rest of the tool, due to intensive use or improper care, can fail at any time. How to determine exactly where the breakdown occurred? Simple logic will help us with this.
If the problem is in the engine, it will:
do not start;
deafen;
work unstable;
overheat;
smoke;
develop insufficient power.
As for all other malfunctions, as a rule, they manifest themselves with a normally operating motor.
If your chainsaw won't start, the first thing to do is to check for a mixture of fuel in the tank. By the way, it must be prepared in the proportions indicated by the engine manufacturer, otherwise the instrument will simply not start.
After verifying that the fuel mixture is correct and available, the ignition system should be checked. To do this, you need to inspect the spark plug.
Her condition can say a lot:
indicates that the fuel mixture does not enter the carburetor, which means that the problem is not in the ignition;
is the result of an overabundance of the fuel mixture, which lies either in a violation of the engine starting algorithm, or in an incorrect carburetor adjustment;
this is a signal about the presence of low-quality oil in the engine lubrication system, incorrect carburetor settings, or an incorrectly prepared fuel mixture.
If the spark plug is splashed with fuel, wipe it thoroughly after removing it. The fuel supply system should also be cleaned. To do this, it overlaps, after which the starter is turned on. A carbonized candle must be carefully cleaned with an awl and emery.
When checking the spark plugs, you should pay attention to the distance between the electrodes (the normal gap is 0.5-0.65 mm), as well as the condition of the gasket and the presence of a spark. A damaged or worn gasket will have to be replaced, and the spark can be checked by putting on the ignition cable, connecting the cylinder and plug nut, and starting the starter.
If the discharge does not occur, the plug must be replaced. In the event that a spark does not appear with a new candle, then the problem is in the connection to the high-voltage wire or in it itself.
If the fuel mixture does not flow into the cylinder, but the spark plug is working properly, this may mean that:
Clogged fuel filter.
To clean this unit, remove the fuel hose and check the jet. If it is weak, the filter must be removed through the filler hole of the fuel tank and cleaned or replaced if completely worn out.
As a preventive measure, it is recommended to replace the fuel filter at least once every 3 months.
This is nothing more than a hole in the fuel tank cap, which is cleaned out with an awl.
The fuel mixture is not supplied or is supplied insufficiently.
There may be several reasons for this:
the air filter is clogged (in this case, it must be removed, rinsed with water, dried and replaced);
the carburetor settings are out of order (which means this unit needs to be re-adjusted);
the integrity of the carburetor membrane is broken (must be replaced);
the channels of the carburetor are clogged (it must be disassembled and all parts and assemblies must be cleaned).
If at low speeds the engine of the chainsaw works normally, but at high speeds it starts to stall and smoke, the problem may be hidden in the muffler.
To check the quality of its work, you should do:
dismantling (with the obligatory closing of the outlet);
disassembly (if the muffler is collapsible);
cleaning from carbon deposits using special detergents or dry method;
drying (using a hair dryer);
reassembly and assembly.
Dry cleaning without respiratory protection is not recommended. The carcinogens present in the soot will be released into the surrounding atmosphere in the form of dust, the inhalation of which is extremely hazardous to health.
To prevent clogging of the muffler during the operation of the chainsaw, you should carefully monitor the composition of the fuel mixture and the quality of its components.
If the chainsaw engine does not start or cannot develop normal power, it is likely that sufficient pressure does not build up in the engine cylinder for combustion of the fuel mixture. The reason for this may be the wear of the elements of the cylinder-piston group - the piston, rings, bearings, etc. In order to assess the condition of this unit, it should be visually inspected, having previously removed the muffler.
For a more complete diagnosis, a compression gauge is placed in the spark plug hole of the two-stroke engine of the chainsaw. It measures the compression in the engine.Based on the results of the check, one can judge the state of the CPG, however, the exact facts can only be obtained with a complete disassembly of the unit.
If the piston is chipped or scratched, it will obviously need to be replaced. The same applies to deformed or broken piston rings - for normal engine operation, they must be completely intact and free of carbon deposits.
A properly working carburetor guarantees maximum efficiency of the chainsaw, that is, it is possible to develop full power with the most economical consumption of the fuel mixture. The adjustment of this unit is usually carried out by the manufacturer, but its design provides for the possibility of adjustment already during operation.
The fact that such a setting will have to be performed by the owner of the chainsaw is evidenced by:
Strong vibrations or damage to the protective cover.
CPG wear.
Carburettor clogged.
Inability to start the engine or its spontaneous stops after starting.
Increase in fuel consumption and emissions while decreasing engine power.
Chainsaw carburetor adjustment is carried out in strict accordance with the manufacturer's instructions using three special screws, which are responsible for the maximum ("M") and minimum ("L") revolutions, as well as the idle speed of the engine ("T"). In order to exclude unwanted interference by an inexperienced user with the carburetor operation, some manufacturers install only one idle screw.
Carburetor adjustment is carried out in two stages:
Basic (carried out with the engine off).
Finishing (carried out with a running, pre-warmed engine).
For basic adjustment, screw in screws H and L as far as the stop and back out 1.5 turns. Final adjustments require the engine to warm up for 5-10 minutes at low revs.
The final calibration is performed by unscrewing the idle screw until the minimum engine speed is reached (in this case, its operation must be stable, and the chain must be stationary). If the engine stops at idle speed, the screw must be returned back, and if the saw chain is still in motion, continue turning counterclockwise.
Calibration check is performed by test:
Acceleration (with a smooth press on the accelerator, the engine should quickly pick up speed to the maximum indicator).
Maximum speed (if there is an ignition interruption, screw H should be slightly loosened).
Work at idle speed (the chain should not move, and the engine should pick up speed as quickly as possible).
If the owner of the chainsaw is not familiar with the carburetor device and does not have the tool necessary to calibrate it, contact a specialist. The carburetor is a very complex unit, so any wrong action can lead to irreversible consequences, for example, complete engine failure.
If the diagnostics showed that everything is in order with the engine and its systems, then the cause of the malfunction should be looked for in other units of the chainsaw. The most common problems are:
failure of the starter;
improper operation of the lubrication system;
incorrect operation of the chain brake;
saw chain wear, etc.
If the cause of the tool failure is not visible to the naked eye, as is the case with the engine, it is necessary to perform a thorough diagnosis of the faults and eliminate them in accordance with the manufacturer's recommendations and safety regulations.
