How to remove a chain from a Stihl chainsaw
Chainsaw Stihl mc 180. a reliable tool at a glance
Chainsaw Stihl mc 180. a tool designed for cutting wood in the transverse direction. The equipment belongs to the category of household appliances. The model differs from professional tools in the material of the working bodies and is designed for use periodically, no more than 40 minutes per work cycle.
DIY saw repair
With the advent of the light and handy Stihl MC 180 chainsaw in the household, it will completely replace the two-handed, bow and even hacksaw. Over time, the chains become dull, the sprockets wear out, the oil supply system is damaged. You can fix some problems yourself. Others require repair at special service centers.
You can check if there is grease in the reservoir, and if it enters the chain with a clean sheet of paper. Direct the tire at a sheet of paper, it should leave a characteristic trace in the form of an oil strip.
You can repair the saw yourself only after understanding the arrangement of the units and the sequence of operations for removing and restoring or replacing the unit. The Stihl 180 chainsaw operating manual will become a reliable assistant. It is in it that you can find installation techniques and a sequence of repair operations:
- oil supply systems;
- bringing the carburetor into working condition;
- repair or replacement of the oil pump.
In addition, the DIYer can shorten the stretched chain and sharpen it.
If the saw chain remains dry during operation or oil leaks, it means that the malfunction and repair of the lubrication system of the Stihl 180 chainsaw is required. At the same time, the oil lines and the tightness of the connection with the fittings are inspected. Be sure to clean the oil supply filter. If the hoses have minor mechanical damage, the tightness can be restored with a sealant.
The carburetor makes itself felt by the difficulty when starting the saw, the running tool does not gain momentum, stalls when throttled. The reason may be the wear of the cuff on the piston, as a result, air is sucked in when discharged. For repair, the carburetor is removed and they get to the cuff on the accelerator, disassembling the unit in the sequence:
- remove the cover with the membrane by unscrewing the screw;
- remove the retaining ring;
- disconnect the air damper, remove the throttle;
- pull out the accelerator with the spring;
- replace the tiny cuffed piston and reassemble the carburetor in reverse order.
Problems may be related to the ignition system. After checking the performance of the candles and cleaning the carbon deposits, adjust the carburetor, supply system and clean the injections. The carburetor is a complex unit and the operation of the chassis depends on its setting. If there is no confidence and skill, it is better to use the services of a specialist. Often, work on low-quality gasoline, with not recommended oil is the root cause of all problems.
To help the master on the resources there is information on how to repair a Stihl 180 chainsaw with your own hands, for example, a video will show the disassembly sequence.
You can see about the diagnostics of the lubrication system here:
Why does the chain come off
Many, even the most experienced users of chainsaws, have encountered in their life a situation where the chain jumped off the guide bar during operation. The most common cause is insufficient chain tension or wear.
In 80% of cases, the stretched chain links slip from the teeth of the drive sprocket, and it flies out from the guide under the action of centrifugal force. Although sometimes the problem appears due to the incorrect position of the sprocket relative to the axis of rotation or a loose saw bar on the chainsaw.
Chainsaw chain sprocket
The sprocket itself is made of durable steel and is located under the cover, it is attached to the engine crankshaft and, thanks to special teeth, drives the saw chain. For different types of chains, sprockets with different numbers of teeth are used. Not only the quality and efficiency of sawing depends on the serviceability of the drive sprocket, but also safety, since the speed of the chain brake also depends on it.
This part is under constant load during the operation of the chainsaw, therefore, its wear is inevitable. However, there are reasons leading to premature wear of the drive sprocket. First of all, this is the incorrect operation of the chain lubrication system. The use of low-quality oil, poor operation of the oil pump, as well as the use of low-quality or faulty chains significantly increases the overheating of the mechanism and, as a result, leads to wear of parts.
There are many models of chainsaw chains on the market now. First you need to know what size is right for your chainsaw and not make a mistake in buying. The second step is to properly install it on the chainsaw. This is a somewhat laborious process, but if you know how to put on and adjust the chain to the saw bar yourself, then the happy owner should not have any problems. We tried to describe in detail the process of installing a saw blade on a chainsaw.
Hopefully, after reading this article, you will succeed the first time. But in order to minimize the occurrence of problems with the chainsaw and chain in the future, do not forget 3 basic rules:
- If the chain is worn out and sagged, replace it with a new one;
- If vibration appears during sawing and the cut is bad. watch the chain tension on the chainsaw;
- Never use saw blades that are defective or repaired by dubious specialists, your health and those of those who are nearby are much more important than a little savings on buying a new and reliable chain.
In the video. replacing the leading sprocket of the chainsaw
Saw chain features
The saw’s working mechanism is a chain. Saw chains are manufactured using a special technology:
- The cutting element is made of high carbon steel, and the use of chrome plating or applying a victor layer to the cutter. The more complex the manufacturing technology, the higher the cost of the chain.
- Hinge holes are sanded to reduce friction and extend life.
- Rivets are used only hardened by a special technology.
- The teeth are marked with marks that can be used to determine wear and perform uniform sharpening.
- After connecting the links into a chain, the product is stretched to ensure dimensional stability during operation.
Intelligent automatic chain lubrication system extends service life. New saws must be selected according to the characteristics specified in the operating instructions for the Stihl 180 chainsaw.
You need to know that chains with victorious surfacing are 3-5 times more expensive than ordinary ones, but it is impossible to sharpen them with your own hands when repairing a Stihl 180 chainsaw. This tool is used more often by employees of the Ministry of Emergency Situations.
For extended maintenance-free periods, use the oil recommended by the tool manufacturer. A special mineral composition is used to prevent chain pitching. It is unacceptable to use oil intended for additive to gasoline for Stihl saws.
It is often asked if the Stihl 180 can be used for longitudinal cuts. The power of the saw allows you to cut wood only across the grain.
The price of the Stihl MS 180 chainsaw is significantly different. The most inexpensive basic model of the usual configuration. The cost of the device depends on the country of manufacture. A German or American product is more expensive than a Chinese one for obvious reasons.
The main reasons for replacing the drive sprocket
The universal wrench is the main tool that will be required when replacing the sprocket.
The most common reasons that force the tool to be repaired associated with the replacement of the drive sprocket are:
- jamming of the chain due to the occurrence of defects during the operation of the unit;
- high wear of the sprocket as a result of long-term operation of the unit.
With regular use of the device, increased wear of the drive sprocket occurs as a result of the application of increased loads on it in the process of sawing wood. There are two ways to operate the device:
- using one saw chain;
- using several saw chains alternately.
When using the first method of operation, the chain is operated until it is completely worn out. This method has several disadvantages. The main one is the problem of monitoring wear during intensive operation of the unit.
When using two or more chains in the process, it is possible to achieve uniform wear of the chains and sprocket, which makes it possible to extend the period of operation of the device before carrying out repairs, which consists in replacing the sprocket. In addition to the wear of the sprocket, one should not forget about the bearing that is installed in the sprocket. This structural element works at any engine speed. When replacing a sprocket, change the bearing at the same time.
The clutch complete with the sprocket must be replaced in a timely manner. If the repair work is not carried out on time during the operation, the tool has increased vibration, which leads to an increase in the wear of the bearings installed in the internal combustion engine on the crankshaft axles. The maximum depth of wear of the sprocket teeth should not exceed 0.5 mm. The life of the sprocket is twice that of a single chain, so two chains should be used during operation. After the chains have reached the end of their life, replace the chains and the drive sprocket at the same time.
Design features of the leading sprockets
Any manufacturer specifies the pitch of the teeth in the instruction manual. Considering that a driven sprocket is also installed on the saw bar (designed to create the necessary tension), the step there and there should be the same.
Chainsaw drive sprockets can be solid and prefabricated. In the first case, the sprocket includes a hub onto which a ring gear is pressed. This is how the parts in Champion chainsaws are arranged. The product should be removed completely when replacing, since at home it is almost impossible to comply with the preload value set at the manufacturing plant. And buying a crown separately is also a problem.
In chainsaws from Stihl or Husqvarna, the replaceable crown is located directly on the drum shaft, and therefore its replacement is not difficult.
Tooth wear is established according to the following criteria:
- There are clearly visible radii in the places of transition from tooth to cavity.
- Tooth width uneven in height.
- Chipped metal at the top of the tooth.
- On the inner surface of the bore in the hub, there are numerous seizures and risks (due to poor lubrication).
- A groove from the saw bar is visible on the sprocket (it is also necessary to change the chain).
- The chain is seized at the initial moment of start.
If at least one of the above factors is present, the drive sprocket must be replaced.
Before starting work (especially if the chainsaw has worked relatively little), it is worth checking the fastening of the saw bar. The tensioning screw has come off or the fastening nuts have been unscrewed. the guide is already misaligned with the longitudinal mowing line of the saw blade. It begins to contact not with the center, but with the periphery of the drive sprocket teeth, provoking their intense wear. After tightening the indicated elements, the operation of the chainsaw is checked: if the backlash is not eliminated, then the asterisk will have to be changed.
How to remove the clutch from a chainsaw and put it back in place?
Diagram of the process of removing the clutch from a chainsaw (for example, let’s take a situation when a drum needs to be replaced):
- remove the saw headset using a universal key;
- remove the chain, tire;
- unscrew the air filter cover;
- then we twist the candle;
- we fix the piston with a stopper or rope;
- remove the clutch with a punch (puller) or a universal wrench to remove the clutch;
- remove the clutch by unscrewing it clockwise;
- remove and replace the drum.
After the steps described above, the entire assembly is carried out in the reverse order.
Unit clutch design
Chainsaws are units that are equipped with drive sprockets, which are a single complex with a clutch basket.
The clutch engages automatically, depending on the number of engine revolutions.
A centrifugal clutch is installed on the units, which works in automatic mode, depending on the number of engine revolutions.
When the engine of the unit is idling or at low speeds, the elements of the clutch basket, which have friction linings, have a certain level of freedom in the radial direction. The presence of freedom of movement leads to the fact that, under the action of the springs, the elements are attracted to the center of the rotation shaft and do not transfer the rotational motion to the sprocket drum. With an increase in the engine speed of the apparatus, the centrifugal force exceeds the force of the springs, which leads to the displacement of the elements with friction linings. These elements are pressed against the inner walls of the drum under the action of centrifugal force. Due to this contact, the rotational movement is transmitted to the drum and the sprocket, which drives the saw chain of the tool. The chain saw sprocket can be located either outside the tool, or under a special cover that protects the mechanism from damage, and the operator of the device from injury.
The main advantage of this type of clutch is that when the saw chain is jammed, elements with friction linings slip, which protects the internal combustion engine from serious damage.
The sequence of repair work
At the first stage, the saw headset is dismantled, the guide bar cover is removed. After removing the cover, the guide bar and saw chain are dismantled. The fastening nuts are unscrewed using the universal wrench, which is included in the delivery set of the unit.
After removing the saw chain and guide bar, the air filter is removed. Then the spark plug is dismantled. In place of the dismantled spark plug, a pre-prepared engine piston stopper is installed. The stopper allows you to fix the position of the piston in the cylinder and prevent the crankshaft from turning. The clutch should be removed using a special puller installed in the socket of the universal wrench. All actions should be carried out clockwise.
After removing the clutch, an approach to the internal parts of the device opens, that is, after removing the clutch, the sprocket can be removed.
After removing the clutch drum, depending on its type, the crown and sprocket are inspected and checked. Depending on the design of this unit, the worn out structural elements are replaced. When carrying out repairs, special attention should be paid to the springs of the centrifugal mechanism and its cams. If wear is found, replace them.
If the components do not cause any complaints, all structural elements are installed on the chainsaw in the reverse order. First of all, unscrew the piston stopper and pull out the starter cord, after which the piston stopper is installed in place. This complex sequence of operations makes it possible to clamp the centrifugal mechanism onto the crankshaft of the unit. The clutch is installed in place and clamped using the universal wrench supplied with the chainsaw. Clamping with a key should be done counterclockwise.
The last stage of the repair work is the installation of the remaining structural elements of the device.
When replacing the sprocket, all work must be carried out carefully and with care. All repair work must be carried out using special tools, otherwise the centrifugal mechanism or the saw chain may be damaged.
The chain transmission of a chainsaw of any design determines the performance of the tool. over, during operation, the chain stretches, and the teeth of the drive sprocket wear out. An illiterate sprocket selection will dramatically reduce the durability of the chainsaw teeth, and its incorrect adjustment will lead to premature wear.
A little about the rules for operating the node
Regardless of the manufacturer’s brand (Stihl, Husqvarna, Partner, Patriot, Makita), chainsaws are divided into household, semi-professional and professional. The difference, however, is not in the quality of the assembly or the manufacture of the components, but in the class of tasks performed, the performance and the continuous power of the drive. This predetermines the choice of the material of the leading sprocket for the chainsaw, its design and the design of the saw chain.
The performance of the tool will be determined by the way the chain-sprocket pair is operated. In most cases, users use one of two options:
- The chain is operated until the teeth are completely worn out, and then both the saw blade and the sprocket are replaced at the same time;
- Periodic replacement of chains with different pitch, and each will require its own drive sprocket.
The choice of option is often determined by the owner’s attitude to his instrument. If it doesn’t matter what to cut (wood or steel staples stuck in it, screws, etc.), then you can stop at the first option. The chain, however, will have to be adjusted periodically, thereby reducing the performance of the chainsaw.
It is strongly not recommended to leave the old chain with a new sprocket and vice versa. When the saw blade is worn out, the probability that the tooth pitch will not match is almost one hundred percent. Therefore, at the initial moment of starting, both components of the chain drive will be subjected to significant dynamic loads. As a result, either the chain will stretch prematurely, “adjusting” to the sprocket, or upon impact, one of the teeth on the drive sprocket will burst.
In addition, it is worth focusing on the operation of the bearing assembly of the drive sprocket shaft. When the saw is operating at working speed, only the crankshaft rotates. But all chainsaws periodically operate at idle speed when the bearing rotates. With a lack of lubrication, the wear of the seat occurs, and. as a result. additional beating of the teeth of the still fully functional chain transmission.
It follows from this that when replacing the chain and the drive sprocket for a chainsaw, it is a good idea to replace the bearing at the same time.
How to change the clutch on a chainsaw?
Owners of chainsaws have probably wondered more than once. how to change the clutch on a chainsaw? On most models of chainsaws, the dismantling and replacement of the clutch can be easily done manually by the owner himself; on a small number of models, the drum can be unscrewed only in a workshop (such chainsaws include, for example, Husqvarna 137 or Partner 351).
In this review, we will learn how to independently remove and change the clutch on a chainsaw, when to do it and what tools you may need.
When to remove the clutch
Disassembly of the clutch for the purpose of removal is carried out in such cases:
- when the spring has burst (the chain turns, the engine runs intermittently);
- the spring has flown;
- a piece of the drum has broken off (in this case, noise will be heard, the chainsaw chain will also spin);
- temporary wear (it’s time to remove and change the clutch due to resource depletion).
Modern chainsaws run on two-stroke engines, which are connected by a gearbox to the saw chain. The chain moves along the tire, and according to the centrifugal principle, idling must remain stationary, that is, it must be safe for the person holding the chainsaw.
If the load on the tool exceeds the recommended load, the clutch will weaken or completely stop transmitting torque to the tire. This will stop the engine. If such situations arise, the clutch wears out, therefore, over time, it needs to be replaced. In the instruction manual for the chainsaw, some manufacturers have information that the clutch is a consumable part, that is, it must be periodically replaced.
Video. how to remove the clutch on a chainsaw:
Carburetor, muffler and ignition coil
To remove the carburetor, it is necessary to have a head 8 and an extension, with which it is convenient to unscrew the nuts securing the carburetor and air filter. Before dismantling the carburetor, it is necessary to disconnect the ignition wire and the choke rod from the engine control lever and remove the lever, only after that the air filter and carburetor are removed.
The Stihl 180 muffler is attached with two nuts, by unscrewing which you need to pull it towards you, it can be easily removed.
The coil is mounted on two screws, to remove you just need to unscrew them.
Disassembly and assembly of Stihl МС 180
Stihl MS 180 is a reliable and unpretentious tool, but sometimes it requires repair, like any technique. In this article, we will consider how the Stihl MS 180 chainsaw is disassembled, which is necessary in the event of an engine overhaul.
- Preparatory stage
- Removing the handle
- Removing the starter
- Removing the flywheel
- Dismantling the clutch and oil pump drive
- Carburetor, muffler and ignition coil
- Removing and disassembling the engine
- Assembling the Stihl 180 chainsaw
The repair of any equipment should begin with the preparatory work, and the Stihl 180 saw is no exception. At the preparatory stage, before the Stihl 180 chainsaw is disassembled, it is necessary to remove the side cover, chain and tire from the chainsaw. Further, using a compressor and a brush, you need to clean the chainsaw from dirt, sawdust, oil drips and other things.
When cleaning the saw, special attention should be paid to the place where the chain saw drive sprocket is located, since this is the most polluted area.
In places with a large accumulation of oil, can be washed with clean gasoline.
How to install a chainsaw chain on a STIHL Farm Boss
Removing the starter
At the next stage, the upper housing cover is removed and the 4 starter mounting screws are loosened, after which it is necessary to remove the oil tank and fuel barrel covers. The starter is removed quite simply and there should be no problems.
After removing the starter, the opened inner cavity of the chainsaw must be cleaned, since usually there is a large amount of compressed small sawdust on the body under the starter.
Removing and disassembling the engine
The engine is held in place by 4 screws installed on the bottom of the Stihl 180 chainsaw. To remove them, unscrew them, then carefully remove the engine from the seat and the rubber pipe of the carburetor.
To disassemble the engine, 4 crankcase screws are unscrewed, and it is removed, then you can remove the crankshaft assembly with oil seals, bearings and piston rings.
Removing bearings and seals usually does not require additional tools, but if the bearings were pressed onto the shaft with force, then a special puller will be needed for dismantling.
To remove the piston from the connecting rod, you will need to remove the retaining ring from the seat using a thin screwdriver, then the piston pin is squeezed out from the opposite side, after which the piston is retracted to the side.
Dismantling the clutch and oil pump drive
With a high head 19, you need to unscrew the clutch. The thread on it is left-handed, so it unscrews towards the tire, and not the back of the Stihl 180 saw.
Having unscrewed and removed the clutch, you need to immediately remove the reflective plate and the oil pump drive, this is easy to do, because they are put on the shaft without any fastening.
Removing the handle
Direct disassembly of the Stihl 180 begins with the removal of the handle, which is attached to the body of the chainsaw using three rubber shock absorbers. To remove, it is necessary to remove the plastic plugs from the inner cavity of the shock absorbers, then, using a powerful screwdriver, squeeze out the upper shock absorber first, then the one closer to the rear handle.
At the back of the handle there is a throttle trigger, which is connected to the carburetor through a wire rod, in order to disconnect the throttle trigger from the throttle trigger, it is necessary to unscrew two screws and disassemble the handle.
When the handle remains on one shock absorber, it is necessary to unscrew the body of the chainsaw from the inside of the handle and bend it to the side, remove the body from the last rubber band.
Removing the flywheel
The flywheel of the Stihl 180 chainsaw is twisted with great effort, so a head with a metal knob is required to remove it. The nut holding the flywheel is unscrewed by the head by 13.
To block the crankshaft from turning, you need to unscrew the spark plug and install the piston stopper through the spark plug hole, if it is not there, you can use the old cord from the starter, with knots tied to it and immersed in the cylinder through the spark plug hole.
It is strictly forbidden to keep the flywheel from turning by installing a power screwdriver and other tools between its ribs and the body of a power screwdriver, with this method of blocking from turning, the flywheel blades are not able to withstand the load and break off.
After the piston is locked in the cylinder, you can unscrew the flywheel nut. The thread in the nut is ordinary, so you need to turn it to the left. Having loosened the nut, it is not necessary to remove it to the end, it is enough to unscrew it until its upper edge is equal to the tip of the shaft, after which a soft metal drift is installed on the nut and a sharp blow is made on it. Thus, the flywheel from a sharp impact jumps off the shaft and can be easily removed without the help of additional tools.