The chain of a chainsaw rotates at idle speed
Why chains for chain saws pull quickly?
A quick check of chain tension is done very simply by grasping the prong and pulling it upwards. If the chain is tensioned correctly, the tail will be 1/3 of its height into the bar groove. If it is too high, it is too tight, and if it is too low, it is too loose.
The saw should normally move freely along the guide bar, without much effort. If the element is difficult to move, it is a sign of excessive tension.
Severe tension on the chain saw’s cutting element causes the guide bar to heat up and wear out, increasing stress on the engine and causing it to quickly wear out. Do not operate the machine with a loose chain because the chain can get caught and break during sawing, which is dangerous to the operator of the machine. The chain can come off the bar and injure your limbs, and it often damages itself and damages the tire. Also, working with a loose chain element causes one-sided wear on the guide bar and causes the machine to cut sharply, leading to sideways movement of the saw.
What you will need
To adjust your chainsaw’s chain tension, you will need:
- Socket wrench for saw head cover nuts.
- Slotted or Phillips head screwdriver under the adjusting screw.
- Heavy-duty gloves for checking chain tension.
A suitable wrench and screwdriver are usually supplied with the chainsaw. Gloves are needed so that you do not injure your hands on the sharp chain. You can also check the tension with two screwdrivers, grasping the chain on opposite sides of the bar for a test twist.
Chainsaw engine malfunction
Signs of chainsaw engine failure:
In certain situations, it is better to seek professional help and take your saw to an authorized service center. But you can do a few things yourself.
In general, in order to eliminate the very cause, you must first correctly identify it, otherwise the entire repair will be tantamount to shooting at sparrows from a cannon, and perhaps even shooting at the “imaginary” sparrows, because there may be no breakage.
If you are trying to start the chainsaw, and it does not start, and it does not make any strange unusual unusual sounds (knocking, grinding), it means that you just start it incorrectly (if you keep the chainsaw on the pump, the engine is flooded with fuel, and after that it is difficult to start it).
What’s the Proper Way to Start a Cold Engine? 1. Push the lever or switch to the “choke closed” position. 2. If the model has a fuel priming pump, pump the fuel mixture into the carburetor. 3. Pull the starter knob until there is resistance, then vigorously pull the hand aside (2-3 times). Don’t try to “rip” the starter cord out of the chain saw! The saw should start, then stop. 4. If the engine fails to start, move the lever to the half throttle or operating position and try starting the chainsaw in that mode. Note: some models have an ignition pushbutton switch, so make sure it is turned on.
What to do if the engine still does not start? First unscrew the spark plug and examine it. It happens that when you start the chainsaw in cold weather, you accidentally fill up the combustion chamber with fuel mixture. In this case you should also unscrew the spark plug, dry the combustion chamber by idling, clean the spark plug, and try to start the saw again.
How to check the spark on the spark plug? Unscrewed spark plug connected to the high-voltage wire, put it on the cylinder and pull the starter. Be careful! Do not touch the spark plug with your hands during this procedure! If you see a blue spark, the spark plug is fine. Re-insert the spark plug, try again to start the saw. If it fails again, check the spark plug wire connection, the coil and the ignition system.
You can tell what’s wrong with the saw by the condition of the spark plug:
- Dry spark plug. Apparently there is no fuel mixture flowing into the cylinder. The problem is not the spark plug, so screw the spark plug back on. And check the fuel system.
- Wet, heavily fueled spark plug. The reason for the fuel surplus is either a bad startup or a carburetor misfire.
- The spark plug is covered with black sludge. It may indicate the use of low-quality oil (so use only original oil for your saw), a misadjusted carburetor, or an improperly prepared fuel mixture. The spark plug should be washed, cleaned well from carbon deposits with an awl or a needle, the electrodes wiped with a sandpaper and screwed back in place.
When checking the spark plug, pay attention to the gap between the electrodes (it should be 0.5. 0.65 mm). Worn gasket must be replaced.
Check and Adjust Carburetor
At service centers, carburetor adjustments are made on special equipment. The adjustment screws have different angles of rotation for each saw (see operator’s manual for details). The need to adjust the carburetor is not necessary very often, especially if you bought the saw from a trusted dealer. All our Husqvarna saws are sent to the service center for adjustment of rpm before sale.
However, failure to fix the adjusting screws sometimes happens.
Causes of failure to adjust the carburetor of the chainsaw:
- Severe engine (pistons) wear. In this case, you need to take more care with the engine, but adjusting the carburettor can improve the functionality of the saw for a while.
- Clogged carburetor due to damaged air filter, poor-quality gasoline, and scale buildup.In such a situation, in addition to adjusting the carburetor, you will also need to flush it.
- Severe vibration of the saw or damage to the fuel cap. It happens very rarely, but there are still cases of.
Signs that indicate the need to adjust the chainsaw carburetor:
- The engine either does not start or starts and immediately stops. This is due to the use of a bad fuel mixture.
- Significant increase in fuel consumption and emissions. Increased exhaust indicates that the fuel is not burning completely. Adding too much fuel may be the cause.
The carburetor adjustment diagram is different for different chainsaw models and is described in the instruction manual. However, the general principle remains the same: It is necessary to change the quantity and quality of the fuel mixture fed into the engine cylinder.
Three screws will help us to adjust the carburetor:
- “L”. low, for low rpm setting
- “H”. high, for adjusting high RPM
- “T” (“LA”, “S”). for adjusting the idle speed (models that have only one screw have the “T” screw)
When adjusting the carburetor of a chainsaw, the following rules should be observed:
- Make sure the saw chain is pointing in the opposite direction from you
- Place your power tool on a stable and flat surface so that the cutting attachment does not touch any metal objects.
Please note: the instructions show the exact angles of rotation of the adjusting screws. Avoid damaging the engine by following these instructions.
There are two steps in the process of adjusting carburetor: the basic one (with stopped engine) and the final one (with warmed up engine).
The chain does not rotate
Why the chainsaw chain does not turn when the engine is running even at full speed?
- Drive sprocket. Either it is jammed, or the crown is so worn that it is not affected and chainThe chain saw does not turn. In any case, you need to assemble the sprocket to find out the exact reason why the chain won’t turn. If the crown is worn, the sprocket must be replaced (or the crown if the sprocket has a prefabricated structure).
- The brake chain is jammed As a result, the sprocket is blocked by the brake mechanism while the motor is running. Stop the motor and release the brake. If this happens under load, the brake mechanism will have to be replaced, as will the sprocket, since many elements can melt and overheat due to the high temperature.
The chain saw has the following causes
Every year, manufacturers develop machinery that is more complex and reliable in design, but easy to operate. Chain saws are no exception. But no matter what advanced features are included in the device, it is difficult to avoid chainsaw malfunction. To diagnose a problem you can do it yourself with the help of the instruction manual. Let’s look at the main types of faults encountered.
Let’s find out the reasons why a chain saw cuts crookedly. It shows up when sawing under load, when the guide bar is pushed sideways little by little. It is especially noticeable when a wide trunk is sawed by double cutting, first from above, then from below. The result is an uneven, angularly cut surface that in some cases is unacceptable. Example. facing bars.
- Uneven sharpening of saw teeth. This is the most common cause of why the device saws askew. Toothing should be uniformly ground to avoid cutting problems. The optimal solution is to buy a sharpening machine that is adjusted to the most worn tooth of the saw mechanism. Or go to a workshop that has such equipment. The result is that all the teeth are the same size.
- The chain or bar you are using does not fit the parameters. When buying these items, note the width of the groove. This is not only important for the equipment to work properly, but also for safety when sawing.
- The saw headset of the device is very worn out. If the saw does not cut well, there may be excessive wear on the headset. Visual inspection will indicate the problem. If the right or left side of the tire is more worn, it must be replaced with a new one. In the event of increased wear it makes sense to perform a complete diagnosis of the lubrication system. This is often the cause of excessive wear on one side of the chain.
In case of a complicated repair it is better to take the technique to a specialized workshop.
If a new chain saw heats up, it is because the piston group elements have not yet fettled. In this case it is necessary to run it in without overheating. If the problem is related to a device already in operation, the cause may be a late ignition. Sometimes the machine overheats because the fuel mixture is mixed incorrectly.
It is not picking up speed
The problem appears at startup. Chainsaw won’t rev, cuts or stops, shuts down, cranks, kicks back when started.
- If the device does not hold idle speed, the causes may be a clogged filter, poor quality fuel mixture, carburetor, ignition module or deformation of motor elements under load.
- If the saw does not develop traction at full power, pay attention to the carburetor. The settings on the power unit may be faulty. Adjust throttle trigger H, which is responsible for cutting under load. Adjust the fuel flow at high rpm for this.
- Does not drop revolutions. The problem is that the unit may accelerate quickly at high rpm and not decelerate. You need to check the throttle function, the toggle switch, the presence of a corkscrew on the throttle shaft.
- Gets up and down uncontrollably. The causes may be in the carburetor, the fuel supply system, the connectors leading to the carburetor.
- Vehicle is running on suction only. Caused by improperly prepared fuel mixture, large amount of oil.
These are the most common causes of this type of problem.
Oil is leaking
Owners of chain saws often face the problem when oil leaks from under the unit from below. The cause is a damaged oil hose that connects to the pump.
Ignition problems are due to weak or no spark on the chainsaw. When checking the spark plug, there may be a blue spark. That tells you that everything is okay. If the spark is gone, check the high-voltage cable. There may be a wire break in it. Another possibility, why there is no spark, is related to the wrong gap between the ignition module and the flywheel coil. The normal rate is 0.2 mm.
No gasoline is coming in
To find the seat of the breakdown and determine why the device does not pump gasoline, disconnect the gasoline line from the carburetor. Try pumping fuel. If it is fed slowly, there may be problems:
Specialists do not fill the tank to the brim. This can put the unit out of order.
If the machine is smoking, power is dropping, look at the engine. Unstable starting, overheating, etc. may also indicate a malfunction.
Chain is spinning at idle speed
If the chainsaw chain spins at idle, it may be due to the following factors:
- The clutch spring is broken. Visual signs: The chain is turning almost always, even if the engine fails to start.
- A piece of clutch chipped off, a spring is off. Signs: chain saw springs back, noises are heard.
- Worn clutch. Signs: frequent slipping of the chainring.
Saw’s headset running at idle speed is due to clutch problems.
Chain does not cut
Performance loss on a chainsaw is caused by dull chain teeth. This is the most common problem, because sharpening needs to be done regularly. How to do this with a machine, file or grinder, read the related article.
Stops at maximum rpm and runs only on the choke
- Air or fuel filter is clogged. Seals need to be cleaned and checked.
- The fan is dead and therefore the fuel is not flowing and the gasoline pump on the chainsaw is not working. Take the needle and gently clean the dichalic.
- Faulty fuel pump. Remove pump and check if gas is leaking from it. If oozing, replace gasket or pump itself.
Blows into the muffler:
- Enriched air/fuel mixture. Why the chainsaw shoots? There is too much gasoline in the mixture and too little air, so the mixture does not burn out completely in the chamber and partially burns out in the muffler. Exhaust deposits are an obvious sign of this. Need air filter cleaning or carburetor adjustment.
Shooting into the carburetor:
- Ignition too late the air/fuel mixture does not have time to burn in the cylinder, so you get a sound like a small explosion.
- Leaky air-fuel mixture. Too little gasoline is getting into the mixture requires adjustment of the chainsaw, or more precisely the jets, to increase the fuel supply. Why Chainsaw does not startPulls on its own for the same reason.
Chainsaw does NOT start
When you have difficulty starting a chainsaw, many people immediately blame the carburetor. In fact, there are several options and the premise of the malfunction can be any:
- Clogged air and/or fuel filter. The problem can be solved by cleaning the filters.
- No fuel in the tank. Yes, there is also such a reason. some owners forget about such an insignificant detail, as filling gasoline chainsaw and think that a couple of liters of gasoline enough for six months. Also, the fuel in the tank should not be stored for more than 14 days.к. the gasoline evaporates and loses its octane rating.
- Check the pipe from the fuel tank to the carburetor. it may have been forgotten or broken, so no gasoline is flowing into the tank.
- There is a spark on the spark plug. Why there is no spark. there may be many reasons: no contact, need to change the spark plug or it is flooded. Why a spark plug fills up on a chainsaw. that’s another question. But if it happened, you need to dry and re-install, then check the spark. If there is heavy soot on the spark plug, it is recommended to replace it.
- Check muffler for sludge build-up. If there is soot. thoroughly clean the muffler, but it is still recommended to take the chainsaw to the service center, so that they checked the cylinder and piston, t.к. soot is a sure sign of improper operation of the elements of the cylinder-piston group.
- The carburetor is out of order. How to properly adjust the chain saw, so that the carburetor worked well, discussed in a separate article.
If none of the above methods helped, it means one of the connecting rod and piston group components is broken. In this case it is recommended to take your chainsaw to a service center.
Let’s find out the reasons why a chainsaw cuts crookedly. This can be seen when sawing under load, when the guide bar is pulled sideways little by little. This is especially noticeable when dusting a wide trunk by double-cutting, first from the top, then from the bottom. The result is an uneven, sawed-off surface that is sometimes unacceptable. An example is when cutting logs.
- Uneven sharpening of the saw teeth. This is the most common reason why a reciprocating saw is misaligned. Teeth should be ground to the same distance to avoid problems when sawing. Optimal solution is to buy a sharpening machine that adjusts to the most worn tooth. Or call a workshop, where there is such equipment. The result. all teeth are the same size.
- The chain or guide bar you are using does not fit the parameters. When buying these items, you need to consider the width of the groove. This is important not only for proper operation of the equipment, but also for safety when sawing.
- The unit’s saw headset is badly worn. If the device does not cut well, there could be excessive wear on the headset. Visual inspection will indicate the problem. If the right or left side of the bar is more worn, it must be replaced with a new one. If there is excessive wear, it makes sense to perform a complete diagnosis of the lubrication system. This is often the cause of excessive wear on one side of the chain.
In case of complicated repair it is better to take the equipment to a specialized workshop.
How to increase the working life of the coupling?
To avoid unplanned repairs, the chainsaw operator should follow certain recommendations. They will help extend the life of the chainsaw clutch and protect it from damage to the main active elements.
- regular lubrication of the clutch parts;
- timely cleaning of the mechanism from dust and dried oil;
- operate the chainsaw only with a fully serviceable guide bar and a well sharpened chain
- Avoid the installed cutting attachment from striking hard metal objects.
Increased wear of chainsaw clutch occurs due to improperly installed brake lever. To avoid further damage, the operator must constantly check the lever, not allowing the chain to rotate while the inertia brake is engaged.
Removing and replacing the clutch with your own hands according to the instructions
Not many sawyers know how to remove the clutch on a chainsaw. The design of mechanisms on different chainsaw models differs, but the principle of operation is the same everywhere. The disassembly procedure is also almost identical, so below we will consider how to unscrew the clutch on a chainsaw with an internal sprocket.
Initially you need to prepare the necessary tools:
- A special wrench called a puller. It is often supplied with the chainsaw
- Screwdriver to unscrew the screws that hold the guard in place
- Spanner. used to unscrew the cowl and tire mounts (comes with the tool)
- Rope. in order to lock the crankshaft. It is best to use asbestos rope, but any kind will do for this purpose. A rope is used if the tool is not provided with a special piston locking wrench
If disassembly is carried out for the purpose of replacement, the new mechanism must be prepared in advance. When buying a new clutch, you only need to know the exact make of chainsaw, as the devices differ in external diameter, threads and construction of the working mechanism. Instructions on how to remove the clutch clutch on a chainsaw is as follows:
The first step is to unscrew the nuts that hold the shroud and bar in place
The procedure is not difficult and does not take long. Reassembly is done in the reverse order of removal. To avoid any malfunctions, it is recommended to install a fully identical clutch on the corresponding tool model.
This is of interest!The same procedure for removing and replacing the clutch for all brands of chain saws Husqvarna, Partner and others.
The chain saw does not start
When problems with starting the chainsaw, many people immediately blame the carburetor. In fact, there are several options and the cause of the malfunction can be no matter what:
- The air and or fuel filter is clogged. Failure is solved by cleaning the filters.
- No gasoline in the tank. Yes, there is a reason. some owners forget about such a minor detail, how to refuel the gasoline saw and think that a pair of liters of gasoline and lubricant. enough gasoline for six months. Not counting that, the fuel in the tank should not be stored for more than 14 days, t.к. The gasoline evaporates and the octane rating goes out.
- Check the pipe from the fuel tank to the carburetor. it could be clogged or cut and no gasoline is getting into the tank.
- No spark on the spark plug. Why is there no spark. the circumstances may be many: no contact, it is necessary to change the spark plug or it flooded. Why does the spark plug fill up on the chainsaw. that’s another matter. But if it is out, you need to dry and re-install and then check the spark. If the spark plug has a heavy deposit, it is recommended to change it.
- Check the muffler for soot. If there is soot. thoroughly clean the muffler, but it is still recommended to take the chainsaw to a service center to check the cylinder and piston, t.к. carbon black is a sure sign of malfunction of concrete parts of the cylinder and piston group.
- The carburettor is clogged. How to properly adjust the chainsaw so that the carburetor works perfectly was discussed in a separate article.
If none of the above methods did not help, it means that the cause of a more serious. breakage of the 1st of the nodes of the connecting rod and piston group. If this happens, take your chain saw to a service center.
How to adjust your chainsaw?
The carburetor is one of the most important elements of a chainsaw, whose main function is to enrich fuel with air and instantly feed the ready mixture into the cylinder of the power unit.
The following signs are indicative of carburetor malfunctions:
- problems with starting the gasoline saw. more effort is required to turn on the motor than usual;
- unstable operation of the internal combustion engine in different modes. unstable rotation of the engine at idle speed, as well as during the transition to low and high revolutions;
- sharp increase in the amount of fuel consumed. on average, the amount of fuel increases by 20-30%;
- increase the amount of exhaust gases emitted. the volume of gases increases by 50-60%, and the fumes themselves take on a dark blue, brown or black color.
The chainsaw adjustment must be performed with the engine in full working order and stable running. Before beginning to adjust will need to wash or replace the filter, check the integrity of the fuel pipes, as well as make sure there are no burrs and other damages on the surface of the cylinder and other parts of the power unit chainsaw.
For the possibility of self-adjustment of the chain saw, its carburetor is equipped with steel spring-loaded screws. Their number and markings depend on the brand and manufacturer of the chainsaw.
The procedure for adjusting the fuel unit for most chainsaws looks almost the same.
The algorithm of actions should be as follows:
- At first the saw must be shut down and wait for its engine to cool down;
- After that, all the screws available in the device of its carburetor should be screwed in the direction of the clock hand to the stop;
- Then each of the screws should be turned one-fourth or one-fifth of a turn in the opposite direction;
- Next it is necessary to adjust the work of the power unit at low revolutions. To do this you need to start turning the respective screw slowly in different directions. As soon as the engine begins to work as quietly and stably as possible, the screw should be left;
- To adjust the idle speed on your chainsaw. pay attention to the chain. If it is rotating on the bar, then you need to find the position of the screw where it will stand still;
- At the end it remains to adjust the work of the internal combustion engine at high revolutions. To do this, you will need to connect a tachometer to the cylinder of the motor and start turning the appropriate screw until the indicators on the scale of the device and the instructions in the instruction manual coincide. For example, if the manual to the saw specifies that its maximum rpm should be 12500 rpm, then the same number should be indicated on the tachometer scale during the adjustment.
To check the chainsaw’s operation after adjustment, you must stop it and wait for the engine to cool down completely. After that you should start the engine and smoothly depress the gas pedal lever. If at the same time the power unit picks up speed smoothly, it means that the adjustment of the saw has been done correctly.
When to retighten the chain
Based on all of the above, we can conclude that the chain on a chainsaw needs to be tightened every time after
- the purchase and assembly of a new tool;
- chain replacement;
- sharpening outside the bar;
- significant stresses;
- hard objects in the sawing area.
In general, the chain on a chainsaw must be tightened if you can see that it has become visually slack. And it is necessary to watch it both before and during sawing.
Is it possible to shorten the chain on your own?
In the case of a chainsaw chain stretched so far that it is no longer stretched, it is necessary to reduce its length.
This is also necessary if the bar is shorter than the chain and an appropriate saw unit cannot be found.
You can also extend the saw element by adding new links, which can be purchased separately or removed from a similar. In stores you can see chainsaw chain wound on coils that are sold by the metre. In general, chain repair for chainsaws can also be done at home, because it is easy to find all the components for it.
How to remove a rivet
To change or shorten parts of the chain, you need to separate the links as follows. Clamp the chain element in a vice and grind away the rivets. the projecting parts. You can use a file or nail file for this. Make sure that the sides of the link are not chipped.
it is not recommended to use an angle grinder, because there is a risk of overheating the links, which will change the physical properties of the metal.
Using the bar (as shown in the photo below), whip out the rivet.
There is another variant of disconnection of links. You do not need to grind the rivet heads. Place the link, namely its rivet, over a hole in the metal or over the slightly divided jaws of a vice. Next, put a locksmith’s chisel on the rivet’s head and strike it several times with a hammer.
Continue to hammer out both rivets alternately as they are rigidly attached by the opposite part of the link. Gradually, the rivets will begin to come out of the top of the link, and it will disconnect.
The advantage of this method is that the rivets can be reused because they are not worn out.
How to join the links
First you need to buy links from a specialty store that match the type of chain you have. You do this if you were grinding off the rivets when disassembling the chain element. Then it is necessary to assemble the link correctly, taking into account the arrows on the link. Place the assembled piece on an anvil and rivet with a light hammer blow.
Don’t be afraid to overtighten, as the rivet has a thickening in the center that serves as a limiter.
Some craftsmen advise connecting the links by welding. This method is suitable if the rivets were ground with a file. But first you need to experiment on some metal to choose the right welding regime.
Welding should be done with a shortened and thin electrode. Rivet is welded to the side of the link, and any extra metal is removed with a nail file. The only disadvantage of this method is overheating of the metal of which the chain elements are made. As mentioned above, overheating can reduce the links’ wear resistance.
When to retighten the chain
Based on all of the above, we can conclude that the chain on the chainsaw needs to be tightened every time afterwards:
- buying and assembling a new tool;
- chain replacement;
- sharpening outside the bar;
- of significant loads;
- hard objects in the sawing area.
In general, the chain on a chainsaw must be tightened if it is visually obvious that it has sagged. And it is necessary to watch it both before and during sawing.
Can I shorten the chain on my own?
If the chainsaw chain has become so stretched that it can no longer be tightened, it is necessary to shorten its length.
It also has to be done if the available bar is shorter than the chain and there is no possibility to find a suitable sawing element.
It is also possible to extend the saw element by adding new links, which can be purchased separately or removed from a similar. In stores you can see chainsaw chain wound on coils that are sold by the metre. In general, chainsaw chain repair can also be done at home, because it’s easy to find all the components for it.
How to remove a rivet
To change or shorten the chain elements, you will need to disconnect the links as follows. Clamp the chain element in a vice and grind the rivets. the protruding parts. You can use a file or nail file for this. Make sure that the sides of the link are not subject to grinding.
Do not use an angle grinder, since there is a risk of overheating the links, which will change the physical properties of the metal.
Using the bead (see photo below for how it looks like), tap out the rivet.
There is another way to separate the links. This does not require the machining of the rivet heads. Position the link, i.e. its rivet, over a hole in the metal or over the slightly divided jaws of a vice. Then place the mechanic’s chisel on the rivet’s head and hit it repeatedly with a hammer.
Continue beating out both rivets one by one, since they are rigidly attached by the opposite part of the link. Gradually the rivets will start to come out of the top of the link, and it will disconnect.
The advantage of this method is that the rivets can be reused, as they do not wear out.
How to connect the links
To begin with, you need to buy links at a specialty store that match the type of chain you have. You have to do it if you were grinding rivets when disassembling the chain element. Then you need the correct assembly of the link, taking into account the arrows on it. Place the assembled piece on an anvil and rivet the rivets with light hammer blows.
Do not be afraid to reattach as the rivet has a thickening in the center to serve as a stopper.
Some craftsmen advise to connect the links by welding. This method is good if the rivets have been filed off. But first you need to experiment on some iron to choose the right welding mode.
Welding should be done with a shortened and thin electrode. The rivet is welded to the side of the link, and the extra metal is removed with a nail file. the only disadvantage of this method is overheating of the metal from which the chain elements are made. As mentioned above, overheating can reduce the durability of the links.