Replacing the sprocket on the Husqvarna 137 chain saw

How to remove and change chain saw sprocket

Chainsaws made by well-known manufacturers of special tools are characterized by high reliability and long service life. This is due to the well-thought-out design and the use of special grades of tool steel, of which all moving and rubbing parts are made. These should include in the first place:

  • A chain with cutting edges;
  • guide rail;
  • The chain sprocket, which is driven in a rotary motion by the energy of a single-cylinder two-stroke gasoline engine.

They all operate in heavy-duty applications and wear out over time. Even slight changes in the geometry of these parts would impair the chain saw’s performance and smooth operation. If you need to remove a sprocket from a chainsaw to replace it, you need to understand how the clutch system works, with which it has a direct connection.

Chrysopere Husqvarna 137. Features and benefits

Since the development of the model Husqvarna 137 chain saw has been very popular among users, this is not surprising, since the brand offers domestic and semi-professional configurations that have taken most of the advantages inherent in powerful professional gasoline-powered saws. Thanks to the introduction of the X Torq system, the Husqvarna 137 chainsaw has reduced emissions to the environment.

Model Features

The Husqvarna 137 chain saw is designed so that all resources remain at maximum performance for extended periods:

  • Auto-Tuning option allows for automatic carburetor tuning.
  • If air comes in, there is secondary filtration, which reduces the strain on the filter.
  • Vibration damping is due to the LowVib function.
  • There’s an easy start option that keeps the Husqvarna 137 chain saw running uninterrupted in all seasons.
  • Chain tensioner is located on the side of the body.
  • A multipurpose wrench is used for a variety of private adjustments and repairs.
  • The drive sprocket is equipped with not only. But also an auxiliary opening for receiving lubricants.

Husqvarna 137 chain saw construction

Husqvarna 137 chain saw is designed with a 2.2 horsepower engine for all types of garden and household chores, plantations, small factories and more. Fuel tank capacity of 0.4 liters. Recommended tire for your Husqvarna 137 chainsaw. H30, and the length can vary from thirty-four to thirty-eight centimeters. Keep in mind that to avoid early wear and unforeseen failures, you can not only meet the manufacturer’s performance requirements, but also use genuine replacement parts for the Husqvarna 137 chainsaw, which are in an affordable price range.

Getting started

  • Adjust cutting assembly.
  • Lubricate the chain when idling.
  • Fill the fuel tank.
  • Start the machine with the starter motor.

How to change the pistons on a Husqvarna 137 chainsaw?

If the Husqvarna 137 chain saw does not start, the first thing to do is to disassemble the saw and inspect the tool’s cylinder and piston group. Parts of this assembly are subject to considerable wear and tear, resulting in chainsaw failure.

When replacing Husqvarna 137 pistons choose parts with a diameter of 3,8 cm. To buy sprockets of the correct size you need to disassemble the chainsaw engine and remove the defective parts. Then you need to install the piston pin and rubber o-rings. After that, you will need to turn the seals 360 °. this will ensure that the rings get into the grooves designed for them.

Constructional features of drive sprockets

Every manufacturer has a tooth pitch listed in the owner’s manual. Since the saw bar also has an idler sprocket (designed to provide the necessary tension), the sprocket pitch must be the same for both.

chainsaw chain sprockets can be solid or assembled. In the first case, the sprocket includes a hub on which the gear ring is pressed. This is how the parts are arranged in Champion chain saws. When replacing the pistons it is necessary to remove the whole product, because it is almost impossible to maintain the factory set tension at home. It is also a problem to buy the sprocket as a standalone sprocket.

On STIHL or Husqvarna chain saws the replacement sprocket is directly on the drum shaft, so there is no problem to change it.

Tooth wear can be read as follows

  • There are clearly visible radii at the transition from tooth to socket.
  • Uneven tooth width and height.
  • Chipped metal on top of the tooth.
  • The hub bore has many scratches and risks on the inside surface (caused by poor lubrication).
  • A groove from the guide bar can be seen on the sprocket (the chain must be replaced as well).
  • The chain jams at the initial start.

If at least one of these factors is present, the drive sprocket needs to be replaced.

Before starting work (especially if the chain saw has not been in operation for long enough) it is worth checking the fastening of the guide bar. Tensioner screw has come loose or fastener nuts have come loose. the guide is misaligned with the longitudinal line of the saw blade. It begins to contact not with the center, but with the periphery of the drive sprocket teeth, causing heavy wear. After tightening these components you can check how the chain saw operates: if the play is not eliminated, the chain sprocket needs to be replaced.

Regardless of the class and purpose of the chainsaw, the cutter includes a guide bar and a saw chain with a tensioner. The manual has information on how to tension the chain on the chainsaw correctly in order to avoid additional stress on the engine and accelerated wear on the chain.

This saw unit is subjected to high and alternating loads, so it must be checked continuously while in operation. A characteristic feature of in-use saw chains is the increase in size due to gaps in the link joints.

Husqvarna 137 chain saw. Replace the clutch drum

The chainsaw clutch drum is one of the chain saw’s most common consumables, because it’s what powers the cutting chain. The drums themselves are divided into two types. with a welded drive sprocket and with a replaceable ring, and in the second case, only the replaceable ring will wear out, the drum itself is replaced much less often.

When repairing the chainsaw clutch, the rule is that if the two chains are completely worn out, the tire is replaced, and if the two tires are worn out, the clutch drum is replaced. The level of wear of the sprocket can be determined without special devices, it is enough to simply inspect it. the chain, moving at high speed, eventually rubs the teeth on which it moves. If the wear is strong enough, then the chainsaw clutch drum replacement is inevitable.

In this article we will talk about Husqvarna 137 chain saw. Replacing the clutch drum is a simple procedure and involves a few steps.

  • Then we remove the air filter cover, unscrew the spark plug, stop the piston of Husqvarna 137 chain saw. It is advisable to use a normal rope for this procedure, as there is a risk of puncturing the piston if a metal stopper is used.
  • The chainsaw is assembled in the reverse order, except for tightening the clutch disc. After threading the clutch, the piston must be re-torqued to prevent deformation of the starter group, which is on the other side of the crankshaft.

Chainsaw clutch drum replacement is an essential part of maintenance that will extend the life of all elements of the cutting equipment. After only a few seconds of use, a new chain on a worn cutting drum will cause the chain to stretch. In turn, this will result in a slight increase in chain pitch, increasing the load on the bearing and sprocket on the bar itself. Therefore, if you decide to save on timely service, then be prepared for the fact that after a short period of time you will need a much more serious investment for the purchase of all consumables of the cutting equipment.

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Causes of early failure of circular saw chains

Rapid elongation of the part during the running-in phase and in the last quarter of the service life. During these time intervals the clothing needs special attention and maintenance.

  • Reasons for rapid chain elongation may be inferior material quality, inappropriate crowning and excessive wear on the drive sprocket, faulty or ineffective lubrication system.
  • Complete chainsaw chain performance also greatly depends on the condition of the bar and drive sprocket, the quality of chain oil and performance of the lubrication system, timely and correct sharpening of the cutting links edges.

Causes of premature chain failure

Rapid elongation of the part during the running-in phase and in the last quarter of its service life. During these time intervals, the set needs special attention and careful maintenance.

  • The cause of rapid chain stretching may be inferior material quality, inappropriate rim configuration and excessive wear on the drive sprocket, a faulty or ineffective lubrication system.
  • To a large extent the chain also depends on the condition of the bar and drive sprocket, the quality of the chain oil, the performance of the lubrication system, the timely and correct sharpening of the cutting edges.

Negative consequences of improper chain adjustment

Checking the condition of the chain and tensioning it is an essential part of the preparatory work.

How well the chain is adjusted depends on

  • the duration of its subsequent operation;
  • Safety in high-complicated sawing operations;
  • the service life of the engine and the chainsaw as a whole.

Overstretched headset dramatically reduces the performance of the work, initiates excessive loads on the power unit and the transmission. There is also overheating of the bar and excessive fuel consumption.

A loose chain can come off the bar or break. The formation of injury-prone moments is partially or completely eliminated by emergency stop systems and catchers that allow more or less success in untangling the chainsaw chain and determining its suitability for later use.

Installing a part with damaged or deformed links can lead to uneven wear of the guide bar groove and other undesirable consequences.

Chainsaw chain sprocket replacement: how to remove and change it with your own hands

Every manufacturer specifies the tooth pitch in the instruction manual. Since the saw bar also has an idler sprocket (designed to provide the necessary tensioning), the sprocket pitch must be identical on both. Chainsaw chain sprockets can be solid or assembled. In the first case the sprocket consists of a hub with a gear ring pressed on it. This is exactly how the parts in Champion chain saws are designed. The complete product must be removed for replacement, since it is virtually impossible to maintain the factory set interference value at home. It is also a problem to buy the pinion as a separate unit.

On STIHL or Husqvarna chain saws the replacement sprocket is directly on the drum shaft, so changing it is very easy.

Tooth wear can be identified by the following symptoms

  • There are clearly visible radii at the transition from tooth to socket.
  • Tooth width is not uniform in height.
  • There are metal chips on the top of the tooth.
  • The hub bore has many scuff marks on the inside surface (due to bad lubrication).
  • There is a groove in the sprocket from the bar (the chain must be changed, too).
  • The chain is jammed during the initial start.

If at least one of these factors is present, the drive sprocket must be replaced.

Before you begin, and especially if the chain saw has not been in operation for long enough, it is a good idea to check that the guide bar is properly secured. Tensioner screw has come loose or fastening nuts have come loose. the guide has become misaligned with the longitudinal line of the saw blade. The clutch begins to contact not with the center, but with the periphery of the teeth in the drive sprocket, causing their heavy wear. After tightening the elements, you need to check the chainsaw: if the play can not be eliminated, the sprocket has to be replaced.

The sprocket can have a split and a pressed ring gear, as was pointed out earlier. That’s why the sequence is different.

For a stationary positioned crown saw, it is necessary to do the following in series:

  • Disassembly of the guard;
  • Removing the guide bar and the chain;
  • Disconnection of the clutch from the motor (piston must be secured beforehand);
  • Removing the clutch clutch together with the drum;
  • Remove the sprocket from the drum with an ordinary open-end wrench (some manufacturers also supply a puller for this purpose).

To reassemble the assembly you have to do it in the reverse order. Some models make it necessary to remove the air filter before dismounting it.

When disassembling a chain sprocket for a chainsaw that has an interchangeable ring gear, the procedure will be almost the same, but in the final stage only the ring gear needs to be replaced.

After having finished the work check the efficiency of the replacement. To do this, check the chain tension: if, when the brake is released and you try to pull the chain in the direction of its movement, it is stationary, the fastener is “overtightened,” and the tensioner should be slightly released.

The success of the work is determined by the presence of a special repair kit, purchased for a particular brand of chainsaw. Otherwise you need to know the size and pitch of the chain saw.

The Husqvarna 137 chain saw is designed so that all resources maintain maximum performance over time:

  • Auto-Tuning option lets you use auto-tuning of the carburetor.
  • If air comes in, secondary filtration occurs, which reduces the strain on the filter.
  • Vibration damping is due to the LowVib function.
  • It has an easy start feature that makes the Husqvarna 137 chain saw uninterrupted in any season.
  • Chain tensioner is located on the side of the body.
  • A universal wrench is used for various private adjustments and repairs.
  • The drive sprocket is not only equipped with. but also an auxiliary opening for receiving lubricants.

This video will show you how to change the chain sprocket on your Husqvarna chain saw.

The sprocket or centrifugal mechanism is a part that resembles a star. The sprocket takes the engine torque and transmits it to the guide bar and saw chain. This ensures the rotation of the cutting attachment and the sawing process itself. It operates in automatic mode that depends on the engine speed.

The clutch drum can be located on the outside of the chain saw or inside, under a separate cover. It has a protective function not only for the sprocket material, but also for the operator, who can be injured by it while working. In addition to the chain rotation function, the saw’s drive sprocket prevents the motor system from malfunctioning when the chain jams or stops rotating.

The drum, located at the base of the clutch mechanism, is an integral part of the chain drive system. This part is shaped like a star, which is how it got its name. Depending on the chainsaw, it can be a professional or a domestic appliance. Since the professional saw is used more often than the household saw, the drive sprocket also needs to be replaced regularly. If we talk about household tools, it all depends on the amount of work performed and the load placed on the chain of the device.

often than not the chainwheel, sprocket and bearing need to be replaced.

In all cases the main reason for changing a sprocket is the chain wear of the teeth in the sprocket. If the saw has a solid drum, the chain surface cuts through the drum almost completely, so the whole part has to be replaced. If your chain saw has a drum with an interchangeable ring, you might just replace the ring.

Replace Worn Parts

If the gear has an interchangeable ring gear, the condition of the base should be checked carefully. If you see any nicks, chips, deep scratches, altered geometry or corrosion you should replace the whole part and not just the gear. Worn and new parts working together in one assembly will shorten the life of the entire assembly. The risk of jamming or chain breakage increases substantially.

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In addition, the vibration load on the clutch, transmission and engine of the device will increase. The same factors will occur if you use the same chain for a long period of time.

Folk “craftsmen” sometimes reanimate the stretched chain blade by simply throwing out one or more links and re-pressing the axles. In this case, the chainsaw requires replacement of the sprocket.

You should also avoid changing the diameter of the gears (and therefore the number of teeth). Working with a larger or smaller sprocket causes forces in the transmission and engine that are not anticipated by the machine designer. This will reduce the service life of the tool and will not increase productivity.

Despite the presence in the chainsaw design safety systems that instantly stop the movement of the blade if it breaks or the tire breaks and protects from the scattering of torn links, it is better not to lead to such situations. The need to replace the drive sprocket is only heightened by safety requirements.

Replace worn out parts

If the pinion has a removable ring gear, you should carefully check the condition of the base. If you find nicks, chips, deep scratches, altered geometry, or corrosion, replace the whole part and not just the ring gear. Worn and new parts working together in one assembly will shorten the life of the entire assembly. There is a very high risk of the chain jamming or cutting off.

Also there will be an increased vibration load on the clutch, transmission and engine. Same factors arise when a chain is used for extended periods of time.

Folk “craftsmen” sometimes reanimate the stretched blade chain, simply throwing out one or more links and re-pressing the axle. If that happens your chain saw needs a replacement sprocket.

You should also not change the diameter of the gears (and, consequently, the number of teeth). Operating with a larger or smaller sprocket causes forces in the transmission and engine that are not anticipated by the product designers. This will reduce tool life and not increase tool performance.

Despite the presence in the design of the chainsaw safety systems that instantly stop the movement of the blade if it breaks or destroys the tire and protects against the flight of torn links, it is better not to such situations. The need for pinion replacement is only reinforced by safety requirements.

The main reasons for changing a drive sprocket

A torque wrench is a basic tool you will need when replacing a sprocket.

The most common reasons that force a tool repair involving the replacement of the drive sprocket are:

  • jamming of the chain due to faults in the machine’s operation;
  • high wear of the sprocket as a result of prolonged use of the machine.

Increased wear on the drive sprocket due to excessive loads during wood sawing operations occurs with regular use. There are two ways of operating the unit:

In the first method of operation, the chain is operated until it is completely worn out. There are a few disadvantages to this method. The main disadvantage is the problem with checking the wear when the machine is used intensively.

By using two or more chains in the process, even wear of the chain and sprocket can be achieved, which extends the period of operation of the device before repairs consisting in replacing the sprocket. In addition to sprocket wear, the bearing in the sprocket should not be forgotten. This design element works at all engine speeds. If the sprocket is replaced, the bearing also has to be replaced at the same time.

The clutch, complete with its sprocket, should be replaced in good time. If repair work is not performed on time, the tool experiences increased vibration during operation, which leads to increased wear of the bearings installed in the internal combustion engine on the crankshaft halves. The sprocket tooth wear limit should not exceed 0.5 mm. Sprocket life is twice as long as a single chain, so you should use two chains when working. After the chains are used up, you should replace the chain and sprocket drive sprocket at the same time.

Main Drive Sprocket Replacement on a Partner Chainsaw

How to Remove and Replace a Sprocket from a Chainsaw?

Many owners of gasoline chain saws are concerned about how to remove the chain saw sprocket after the device has broken.

When replacing the sprocket, all work must be done with care and caution.

The design of the device is a chainsaw is a classic mechanism that is powered by an internal combustion engine. The machine uses one of the more common single-cylinder, two-stroke carburetor engines that run on gasoline. The simplicity of the motor and the chainsaw’s overall design is a guarantee of trouble-free and dependable operation in harsh operating conditions. A chainsaw is very easy to operate and does not require a great deal of skill. The only prerequisite for long and trouble-free use of the unit is the implementation of continuous inspection and maintenance of the unit. You should replace worn parts often as you operate the machine. To reduce tool wear, keep a close eye on the chain lubrication quality, chain tension, chain wear, and drive sprocket wear.

Before you start repairing a chain saw, you should understand how it is designed. To perform the replacement of the 1st of the main parts of the construction of the unit. the drive sprocket. it is required to learn the principle of the unit’s clutch.

Unit clutch design

Chainsaws are units that are equipped with drive sprockets, which are a single unit with a clutch basket.

replacing, sprocket, husqvarna, chain

The clutch is engaged automatically depending on the RPM of the motor.

The units are fitted with a centrifugal clutch that operates automatically, depending on the number of motor revolutions.

When the machine motor is running at idle or low RPM, the friction lining elements of the clutch have a certain amount of freedom in the circular direction. This freedom of movement allows the elements to be drawn to the center of the rotary shaft under the action of the springs, and does not transfer any rotary motion to the sprocket drum. When the rotational speed of the machine motor increases, the centrifugal force exceeds the force of the springs, which causes the parts with friction plates to move. These parts are pressed against the inner walls of the drum by centrifugal force. This contact results in a rotary motion transmitted to the drum and sprocket that drive the saw chain of the tool. The chainsaw sprocket can be placed 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 chain jams, the parts that have friction pads slip, which protects the gasoline engine from severe damage.

The main reasons for replacing a drive sprocket

A universal wrench is the main tool you will need when replacing the sprocket.

Drive sprocket for chainsaw

Chain saw drive sprocket or clutch plate, is used to transmit the rotary motion and power to the saw chain. There are three different types of drive sprockets;

Solid sprocket. This sprocket has a clutch plate that is hardwelded to the drive sprocket. If worn, the entire sprocket is replaced.

A collapsible sprocket. The clutch plate with splines that fit the drive sprocket rider. The clutch plate has very little wear and a replacement sprocket is very inexpensive. The collapsible sprocket is very advantageous for large amounts of work and is mostly used by professionals.

Replaceable Sprocket Sprocket. This sprocket is used for replacement on collapsible sprockets.

You choose your drive sprocket by chainsaw model. If you’re in doubt about your choice. give us a call, we’ll try to suggest the right replacement part.

Chainsaw sprocket and its functions

Before figuring out how to change the sprocket on a chainsaw, it’s worth understanding what sprockets look like and the problems associated with them. Sprockets have sprocket teeth that guide the chain outside the sprocket for smooth operation. Rim sprockets: Rim sprockets have a rim that moves freely around a spline to guide the chain around a rod with internal teeth.

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Drive sprocket. This is a very important and often overlooked part of chainsaw maintenance. Drive sprockets are selected according to the length of chain you are using. They should be changed every 2 to 3 chain changes. Try to determine which rim or sprocket you have. Installing the rim and sprocket means it’s easier and cheaper to replace the rim, which is the part that drives the chain. They wear out faster, but they are cheaper. The rim must be replaced when it has worn down by 0.2 mm.

Changing the rim on STIHL chains is easy. On chainsaws where the rim is inside the clutch, such as some Husqvarnas chainsaws, you must first remove the clutch.

Sprocket sprockets drive the chain directly from the sprocket teeth on the sprocket itself. When they are worn, the entire sprocket must be replaced. They tend to wear out more slowly, but cost more when you replace them.

Side sprockets and rear clutch sprockets are easy to change. Integrated sprockets are more difficult to remove because the clutch assembly must first be removed. This requires that you pull the spark plug and turn on the piston stop tool.

READ Adjusting the carburetor on a Husqvarna chainsaw

If you continue to use a worn sprocket, it will begin to damage the drive links, which, in turn, expand the groove of the groove, which then gives a poor cut, which further accelerates the wear of all parts! This is a particular problem with longer rods.

Sometimes the bearing on the sprocket needs to be replaced. It’s a simple case of removing the sprocket, extending the existing bearing and replacing it with a new.

Husqvarna 137/142 quick repair. Replacing the oil pump.

A common problem with Husqvarna 137 and 142 chain saws is an oil pump failure. This video shows how to quickly change the oil pump.

Chainsaw clutch closes the sprocket.

First of all, it should be noted that when buying parts for a chainsaw, it is necessary to strictly comply with the type of drum or use the advice of a specialist, if it is about its modernization. Usually, when the drum and saw chain are replaced at the same time, the drum bearings are also replaced.

STIHL professional chainsaws

In operation there are already several dozen chainsaws of different manufacturers, capacities, and, most importantly, special purpose. Divide saws into:

Accordingly, the drive gear in them will be different, as well as the sequence of operations. This is a peculiarity of saw gear units. Most professional saws have a guide bar that can be repositioned in two different planes.

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And in this article, you can learn how to repair the chainsaw “Parter 350”.

In operation there are already several dozens of chain saws of different manufacturers, capacities, and the main thing is special purpose. Saws are subdivided into:

Accordingly, their drive gears will be different, as well as the sequence of actions. Discover the 253 best selection of Husqvarna chainsaw sprocket 142 chainsaw chainsaw replacement. Husqvarna 142 chainsaw assembly. Husqvarna 140 chainsaw. Chainsaw sprocket replacement. Husqvarna 340 chain saw repair sprocket replacement.

The drum, located in the clutch base of the mechanism, is an integral part of the chain drive system. This part in its own form reminiscent of the star, due to which it received its nickname. How to Change a Drive Sprocket in a Chainsaw, on a Clutch. How to change a sprocket on a chainsaw | video on.

Depending on the type of chainsaw detail can be professional or consumer. Because the chainsaw is used more often than a domestic saw, the drive sprocket needs constant replacement. How to disassemble the engine on a chainsaw Druzhba. If we talk about household tools, then there is everything depending on the amount of work performed and the load exerted on the chain device.

To learn more about chain saw faults and what to do about them click here.

When using a tool such as a chainsaw on a regular basis, it is important to perform regular diagnostics by replacing consumables and parts. One such consumable item is the sprocket or chain drive mechanism. If the question arises about how to remove the sprocket from a chainsaw correctly, it is time to replace it. When and how the correct replacement of chain saw sprockets is performed, let’s consider below.

The problem is complicated by the design of brand-name chainsaws, which provides for the replacement of the worn drive only after the complete dismantling of the clutch mechanism and other components. Alternatively, in order to remove the sprocket from the chainsaw, it is necessary to have a special wrench.

A design feature of much of the chainsaw import is the placement of the sprocket on the clutch mechanism.

  • If there is significant tooth wear, the drum, which is one piece with the drive unit, needs to be replaced.
  • advanced design of the drive sprocket makes it possible to rehabilitate the part by replacing the ring gear.

This tool is very rare in the list of factory kits that come with the saw. The problem can be solved by replacing the worn-out part at a service workshop or by making the necessary fixture at home.

Drive sprocket replacement technology requires the entire job to be done in a given sequence:

  • removal of the headset and air filter;
  • installing the piston retainer in the spark plug hole;
  • the clutch clutch and gear drive made together with the drum are removed with a puller, the sprocket can be unscrewed only in a clockwise direction.

If wear of the cage, centrifugal mechanism springs and cams is detected, it is recommended to replace the whole set.

If there is no doubt about the condition of the parts you have removed, reassemble the saw in the reverse order. To reliably secure the clutch to the crankshaft simply unscrew the piston stopper, pull out the starter rope, and return the starter to its original position.

READ Chain Feed Oil Adjustment on the Husqvarna Gasoline Chain Saw

We should warn amateur craftsmen against simplifying the requirements of repair technology and saving money on the installation of relatively cheap Chinese components.

The quality of the work done is guaranteed by attention, accuracy, observance of the sequence of all disassembly and assembly operations.

  • removal of the protective cover and the bar and cutter bar set;
  • locking the piston part of the motor;
  • disconnecting the clutch from the motor system;
  • Removal of the clutch clutch and centrifugal sprocket from the saw body;
  • visual inspection of the sprocket and its gear part;
  • replacement of the sprocket with a new clutch drum if defects are found;
  • Diagnose chainsaw clutch components for defects. worn centrifugal springs and cams can adversely affect sprocket operation;
  • if there are no malfunctions, move on to the assembly stage. To do this you need:
  • remove the stopper;
  • pull back the ignition cable;
  • screw a stopper to fix it on the motor shaft of the centrifugal mechanism;
  • use a multi-purpose wrench to clamp the clutch in the counterclockwise direction;
  • Put the remaining parts you removed back in their original positions.

The second method on how to unscrew the sprocket on a chainsaw with a collapsible clutch drum looks simpler than the previous one. The procedure will be similar, but it will not be the whole sprocket that has to be disassembled and reinstalled, but only a part of it, the ring gear.

Do not forget that installing a new chain on a chainsaw bar is one of the reasons to re-equip the saw with a new sprocket. Otherwise the chain will stretch prematurely or break while you’re working. Less clutch drum wear is obtained by alternating the use of several chains and periodic maintenance of its bearing.