Changing the drive sprocket on a STIHL 180 chain saw

STIHL 180 chain saw sprocket replacement

Every system sprocket manufacturer has a tooth pitch listed in the owner’s manual. Since the guide bar also has an idler sprocket (for proper tensioning) the sprocket pitch must be the same for both types of chainsaws. Chainsaw chain sprockets can be sprocket sprockets in one piece or as a complete unit. In the first case, the sprocket consists of a hub that holds the sprocket on top of the sprocket. This is exactly how the parts in Champion chain saws are designed. When changing sprockets, the complete sprocket is best removed, since the factory set tension value is virtually impossible to maintain at home. Buying a sprocket separately is also a problem.

On STIHL or Husqvarna chainsaws, the replacement sprocket is mounted directly on the shaft, and is therefore easy to replace.

Tooth wear is established by the following signs:

  • There are clearly visible radii at the transition from tooth to trough.
  • Tooth width is not evenly spaced.
  • Chipped metal on top of the tooth.
  • Numerous scratches and marks on the inside of the hub bore (caused by bad lubrication).
  • A groove from the guide bar can be seen on the sprocket (the chain must be changed as well).
  • The chain jams when it is first started.

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 that the bar is properly secured. Tensioner screw has come loose or fastening nuts have come loose. the guide is out of alignment with the longitudinal line of the saw blade. The sprocket nose does not touch the center of the sprocket, but the tooth flanks on the sprocket teeth, which causes heavy wear. After tightening the above elements, check the operation of the chainsaw: if the play is not eliminated, the sprocket will have to be replaced.

The sprocket can have a split or pressed ring gear as noted above. That’s why the sequence of operations is different.

For a stationary located girth gear, the sequence is done:

  • Dismantle the cover;
  • Removing the saw bar together with the chain;
  • Disconnecting the clutch from the engine (the piston should be secured beforehand);
  • Removing the clutch and the drum;
  • Removing the ring from the drum with an ordinary open-jaw wrench (some manufacturers also include a puller in the spare parts kit).

Assemble the assembly in the reverse order. For some models, before dismantling the crown, you will also have to remove the air filter.

When disassembling the chain saw drive sprocket, which has a replaceable ring gear, the order of work will be almost the same, but in the final stage only the ring gear must be replaced.

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

Successful work is determined by a special repair kit, purchased for a particular brand of chainsaw. Otherwise you need to know the exact size and pitch of your saw.

The Husqvarna 137 chain saw has been designed so that all resources remain at their best for a long time:

  • Auto-tuning option allows for automatic carburetor adjustment.
  • If air enters, secondary filtration occurs, which reduces the load on the filter.
  • Vibration attenuation is due to the LowVib function.
  • There is a possibility of easy starting, thanks to which the work of Husqvarna 137 chain saw is not interrupted at any time of the year.
  • Chain tensioner is located on the side of the body.
  • For various private adjustments and repairs, there is a universal wrench.
  • The drive sprocket is not only equipped with. But also an auxiliary hole to receive the lubricants.

This video will help you change the drive sprocket on your Husqvarna chain saw.

The sprocket or centrifugal mechanism is a part that resembles a star. It takes up the engine torque and transmits it to the guide bar and saw chain. It ensures the rotation of the cutting attachments and the sawing process. It is triggered automatically and depends on engine speed.

The clutch drum can be located outside or inside the chainsaw, under a separate cover. It serves not only as a safety mechanism for the sprocket material but also for the operator who can be injured by the chain while working. In addition to the chain rotation function, the drive sprocket prevents the motor system from malfunctioning if the chain jams or stops turning.

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 why it gets its name. Depending on the chainsaw, it may be a professional or a home appliance. As a professional saw is used more often than a domestic one, a chain saw chain sprocket needs to be replaced on a regular basis. If we talk about domestic tools, then everything depends on the amount of work performed and the load that is put on the chain of the device.

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The sprocket, sprocket pinion, and saw bearing most often need to be replaced.

In any case the main reason to change the chainwheel is the chainwheel’s teeth are worn. In the case where the device has a monolithic drum, the surface of the chain cuts through it almost completely, which also requires a complete replacement of the entire part. If chain saw has a drum with a removable sprocket, in this case you can replace the sprocket only.

How to change it with your own hands

Experienced craftsmen recommend the following sequence of operations when replacing a sprocket:

  • Remove the housing and air filter (if necessary).
  • Unscrew the spark plug and use the spark plug lock to secure the piston.
  • Remove chainsaw clutch.
  • Remove the piston pinion with a puller or open-ended wrench.

Unscrew the detachable ring clockwise. If you disassemble and find the centrifugal mechanism components worn or broken, remove and replace them as well. If parts and assemblies are visually undamaged, the mechanism is assembled in the reverse order.

How to remove the chain saw sprocket with your own hands

To correctly and accurately fix the clutch mechanism on the actuator shaft, remove the piston retainer, carefully pull the starter cord and release it.

How to assemble the drive sprocket on a chainsaw

Virtually all newer chainsaws use a centrifugal clutch system. A specific feature of this mechanism is that when the gasoline engine reaches maximum rpm, the clutch drum starts automatically and transmits the rotation to the drive sprocket. This puts less strain on the main parts of the tool, extending service life and increasing productivity.

Diagram of the sprocket assembly

The clutch drum, where the sprocket is located, can be located on the inside or outside of the chainsaw body. There is always a cover on top to protect the moving parts from dirt, sawdust and dust. The clutch itself. is the metal disc in the clutch drum. The whole mechanism is attached to the engine crankshaft by bolts with springs, on the edges of which there are friction pads. When motor rpm exceeds a certain value, centrifugal force is created, exerting strong pressure on the inside of the drum. The sprocket is then started. The chain saw begins to rotate.

READ What is the best chainsaw for your home?

How to assemble?

Assembly of the clutch mechanism should be carried out in the reverse order. First install the sprocket on the needle bearing, then put on the drum, the washer, the gasket and the clutch itself. Tighten in counterclockwise direction and lightly clamp the piston.

If your chainsaw is an oil-driven spring, it can be built into the drive sprocket. In most models, the correct location of this element is indicated by a special color or notch. To get to the correct position, rotate the sprocket until it clicks.

The last stage of assembly. installing the guide bar. During this process, you must release the handbrake, and then check that the chain teeth are inserted into the appropriate grooves. After installation, set the chainsaw chain to the operating position. Finally remove the plug, screw in the spark plug and replace the filter. The final stage of the repair is to fasten the protective cover of the housing.

Types of guide sprockets

There are two kinds of drums, depending on the purpose of the chainsaw, professional and consumer. This will affect how often the sprocket is replaced: if a home saw is used far less often than a professional saw, then consumables like the sprocket, bearings or roller need to be replaced less often, too.

There are two types of drive sprockets by design:

    Solid or non-disassembly type. As the name implies, this is a one-piece design where the clutch plate and drive ring are solidly welded or pressed together. If necessary, the entire part can be replaced.

To the left of the clutch drum (aka sprocket) is a needle bearing.

On the right of the clutch drum is the replacement ring.

Once you have determined the type of your saw and the sprocket to be replaced, you can begin the process of updating the mechanism.

How to remove the chain saw sprocket: a few options for different clutch drum designs

Method for a sprocket with a fixed crown

  • Removing the blade guard and the guide bar;
  • clamping the piston part of the motor;
  • Disconnecting the clutch from the motor system;
  • the notch in the saw housing of the clutch coupling and the centrifugal sprocket;
  • Visual inspection of the sprocket and its gear part;
  • if defects are detected, replace the sprocket with a new clutch drum;
  • diagnose chainsaw clutch components for defects. worn centrifugal springs and cams can adversely affect the operation of the sprocket;
  • if there are no malfunctions, go to the reassembly phase. To do this: remove the stopper;
  • pull back the ignition cable;
  • screw the stopper to fix it on the motor shaft of the centrifugal mechanism;
  • use a universal wrench against the chain to clamp the clutch;
  • return the remaining removed parts to their original positions.

Method for a star with a collapsible clutch drum

Don’t forget that installing a new chain on the chainsaw bar is one reason to re-equip the saw with a new sprocket. Otherwise the chain will stretch prematurely or break in the process. Less wear on the clutch drum is obtained by alternating the chains and periodic maintenance of the clutch bearing. This mechanism is engaged only at idle speed: it is not engaged when the speed increases. Experts recommend changing it in conjunction with the chain and sprocket and lubricating it systematically with chain oil.

Ways to help prolong the life of a chain sprocket

To extend the life of your drive sprocket, adhere to the following rules:

  • Operate about 3 chains.
  • Maintain the sprocket bearing. Make sure it is always lubricated with quality grease. Standard sprocket bearing grease from

If you want to save money and sharpen the sprocket yourself, don’t do it. It is not so expensive, and the attempt to repair the part by your own hands may turn out to be against you. Experts recommend not saving on this and at the first sign of wear, purchase and install a new sprocket.

Is it wise to try to resharpen or repair the chain sprocket??

To replace the drive (drive) sprocket, you will need the following tools and accessories:

changing, drive, sprocket, stihl, chain
  • a special key for the removal of this part (usually supplied with expensive brand-name chainsaws, cheap saws do not have such a key);
  • poke in aluminum or copper (soft metal only, and only if you do not have a wrench)
  • a hammer (to hit the hammer while unscrewing the sprocket);
  • a flat-blade screwdriver for tightening the nut;
  • sprocket bearing grease.

Design problems, differences between different models

Brand name chain saws have a special design that makes it impossible to replace a worn actuator without dismantling the clutch and other parts of the chain saw. That means that the saw has to be almost completely disassembled. modern models of expensive chainsaws are always supplied with a special wrench.

The chainsaw owner may also encounter the following problem: on Chinese-made imported chainsaws or electric saws the sprocket on the clutch mechanism may be in an unusual position. On older models, if the chain teeth are worn, you need to unscrew and replace the drum, one piece with the drive. On newer models, the sprocket can be replaced separately.

Saws types and specifications

Convenience and reliability make the STIHL mc 180 chain saws very popular with hobby chainsaw enthusiasts. Basic model weighs only 3.9 kg. The 35 cm long saw blade is ideal for cutting logs or for cutting and dropping trees up to 30 cm in cross-section. Two-stroke motor power of 2 liters. с., Allows you to do household chores connected with crosscut sawing of boards and even firewood of any kind of tree. The fuel tank capacity is only 0.25 l, but it allows to work without stopping for 45-55 minutes.

To use for the filling it is necessary to mix the recommended oil or transmission oil with unleaded gasoline AI-92 and AI-95. Ratio. 25 ml of additive per liter of gasoline.

STIHL chain saw 180 chain is a continuous, closed-loop chain with 50 links. Other features:

Operating mechanism, the saw unit, includes guide bar, sprocket and automatic lubrication system.

The chain tensioning system is located on the side, which is comfortable. A brake device for the chain is foreseen.

Depending on the bar length and the upgrading of the STIHL MC 180 chain saw, there are a number of variations. Saws with a length of 35 cm refer to the models, which are labeled 14, their length in inches. The same set on the engine and its characteristics, but with a bar length of 40 cm, are called MS 180 16. STIHL mc 180 C-VE chainsaw is a higher class tool. It has a 40 cm long guide bar, easy-starting system and quick tensioning system for the chain. Easy access to air intake filter, conditioned to extend tool life.

changing, drive, sprocket, stihl, chain

Instruction manual compliance is the key to long machine life

Every machine has an instruction manual, even the more complex STIHL 180 chain saw. Before you make the first start, you need to study the technical control. This is especially important if you already have experience with the Druzhba saw. Different assembly, chain tensioning system, starting and adjustment procedures require more familiarity. There are reports on the forums that the sawyer poured the spark plug at the first start. repeatedly pulling the starter, it is necessary:

What not to be a hassle, gasoline must be produced to the end, not left in the tank “sour” for a number of days.

The operating instructions provide a verbal definition of the markings on the tool body. There is also a parts list, how to disassemble STIHL 180 chain saw for parts replacement and chain sharpening.

Warnings on working with high-risk tools and non-hazardous procedures will help to avoid injury. When changing the chain, it is very important to check if the chain is recommended by the manufacturer. When performing a sprocket change, the chain saw Taiga Not Sprocket Change Chainsaw. Changing the sprocket on if your chain saw For the best brands of STIHL or. Improper assembly can result in damage and warranty claim may not be met.

Follow the instructions. the basis for a long service life of the machine

With any tool, even more complicated, like the STIHL chain saw 180 comes with a manual. Before the first start, the technical controls should be known. This is all the more urgent if you already have experience with the Druzhba chain saw. Different assembly, chain tensioning system, starting and setting conditions of the tool need preliminary acquaintance. There are reports on the forums that the sawyer poured a spark plug on the first start. repeatedly pulling the starter, it is necessary:

In order not to get into trouble, it is necessary to produce gasoline to the end, not to leave it in the tank to “sour” for a number of days.

The manual includes a definition of the marking on the chain with a few words. There is also a parts diagram, order of disassembly of chain saw STIHL 180 for replacement of components, chain sharpening.

Warnings on dangerous tools and non-hazardous procedures help to avoid injury. When changing the chain, it is important to always check that it is recommended by the manufacturer. When performing a sprocket change, the chain saw Taiga No Sprocket Change. Changing the chain sprocket on your STIHL chain saw For the best brands of STIHL or. Improper assembly may result in damage and will not meet the warranty service criteria.

saw repair with your own hands

The new lightweight and handy STIHL MC 180 chain saw will completely replace a two-handed saw, bow and even a hacksaw in your household. Chains wear out over time, sprockets wear out, and the oil system is damaged. Some problems can be corrected by yourself. Others require repairs in an authorized service center.

Check whether there is grease in the tank and whether it is flowing to the chain, you can use a clean sheet of paper. Point the guide bar at a piece of paper, it should leave a characteristic trail in the form of an oil strip.

To do this yourself, you need to understand the construction of the components and the sequence of operations for removing and repairing or replacing the saw. STIHL chain saw STIHL 180 Instruction Manual is a straightforward, reliable source of advice. That is where you can find installation methods and repair sequences:

The DIYer can also shorten an overstretched chain and sharpen it.

If the chain is still dry when you use it, or if it is leaking oil, STIHL chainsaw lubrication system troubleshooting and repair is necessary. This is done by inspecting the oil lines and the tightness of the connection to the fittings. The filter in the oil inlet must be cleaned. If there is minor mechanical damage to the hoses, the tightness can be restored with sealant.

The carburetor makes it hard to start the saw and the tool doesn’t pick up, or stops when you throttle it. Piston seal may be worn and may be the reason, as a result air is sucked out at low pressure. To repair, the carburetor is removed and the collar on the gas pedal is reached by disassembling the assembly in sequence:

  • remove the cover with the diaphragm by unscrewing the screw;
  • Remove the retaining ring;
  • disconnect the air damper, remove the throttle;
  • pull out the gas pedal with the spring;
  • Replace the tiny piston and collar and reassemble the carburettor in the reverse order.

Trouble with the ignition system could be. After checking the performance of the plugs and cleaning the fouling, adjust the carburetor, feed system and clean the injectors. The carburetor is a complex assembly, and its adjustment affects the operation of the chassis. If you lack confidence and skill it is better to use the services of a specialist. Working with low-quality gasoline and unsuitable oil is often the root cause.

Here you will find information on how to repair STIHL chain saw STIHL 180 with your hands.

To see how to diagnose the lubrication system, click here:

Disassembling a STIHL Chainsaw 180. DRIVE2

The STIHL MS 180 is a reliable and rugged machine, but it can be damaged or has to be repaired just like any other piece of kit. This article shows you how to disassemble a STIHL mc 180 chain saw and what you need to do if you want to overhaul the engine.

Good day to you all!A long time I did not write anything in the blog, that was busy (work and dacha (house in the country) and more decided to dismantle the barn and build a bathhouse), but here’s the occasion. chain saw STIHL saw and stalled Truth is because I forgot to fill it up, but I’m not looking for easy ways. I opened the air filter to see the dirt and after cleaning the saw did not start I thought that may be that the carburetor got. you need to dismantle Well, I thought that the tank is full, I tightened the chain and oil to the chain refueled.

What I’m a little deviated from the topic Let’s disassemble. Before removing the side cover from the ignition, remove the covers from the fuel tank and the oil.

Remove the ignition coil by removing a couple of bolts.

After unscrewing three self-tapping screws remove the ignition cover

Next is the removal of the air intake and the carburetor

unscrew two nuts and remove the air intake

on the same studs and the carburetor and remove it

Then we remove the fuel tank. The hose was removed when removing the carburetor.Next, you should remove the shaft (I’ll call it a shaft on and off the chainsaw (since I do not know the correct name)) on one side is removed at the top, then pull the other end to the side.

After should remove the muffler, also unscrewing the two nuts, I forgot to make a photo.

You can already proceed to the dismantling of handles that hold the whole structure, and this requires a screwdriver to remove the three plugs

In order to continue to remove the clutch, it is necessary to unscrew the nut, and to do this, it is necessary to lock the crankshaft.I did the following. I unscrewed the plug and in this hole put a string with knots pre-turning the rotor and looked in the hole removed from the muffler, that the piston was in the bottom dead center

watching the piston by turning the rotor

here you can unscrew the nut. clutch nut has to be unscrewed in the direction of the picture. there are also some simple parts (needle bearing, cover and plastic bushing with thread and stop. everything is easy to take out.

Do the same with the rotor nut

The rotor should be carefully knocked off the shaft, and there are grooves on the shaft and rotor itself (don’t forget about them when assembling)

That’s almost all, the only thing left is to take the engine out of the plastic housing, disconnecting the rubber bands on the housing with the intake port on the cylinder. Finally, one more photo for those who want to remove the crankshaft with the piston

After loosening these four bolts, remove the crankshaft and piston

I don’t have any use for that, since I’m just going to clean and tidy everything up.Good luck, everybody!

Why does the chain come off??

Many chain saw users. even the most experienced ones. have had to deal with a chain jumping off the guide bar during operation. The most common cause is insufficient tensioning or wear of the chain.

In 80 percent of all cases, the tensioned chain links slip off the sprocket teeth and the chain runs off the guide bar due to centrifugal force. Sometimes the problem is caused by the wrong position of the chainwheel in relation to the axis of rotation or a loose bar on the chain saw.

Basically the chain is stretched for 3 main reasons: low quality metal, installation with excessive tension, use of low quality oil. Also recommend you read about chain saw chain oil, STIHL and Husqvarna oils.

Saw types and specifications

The STIHL mc 180 chain saw is in demand among hobbyists because of its convenience and reliability. The entry-level model weighs only 3.9 kg. Sabre, 35 cm long blade allows you to cut logs or drop trees up to 30 cm in cross-section. Two-stroke engine capacity of 2 liters. с., which allows you to perform all household chores associated with cross cutting boards and even firewood from any tree species. Only 0.25 litre fuel capacity, but that allows you to work for 45-55 minutes non-stop.

To fill it up, use a mixture consisting of recommended or transmission oil with unleaded gasoline AI-92 and AI-95. Ratio. 25 ml of additive per liter of gasoline.

The STIHL 180 chain saw chain is a continuous, closed-loop, 50-link chain. Other parameters:

The operating mechanism, the saw headset, includes the bar, sprocket and automatic lubrication system.

Side-mounted chain tensioning system for convenience. Braking device for the chain.

Depending on the length of the bar and modernization of the STIHL chainsaw mc 180 there are several modifications. The saw with a 35 cm long blade is one of the models that have a 14 in. The same set in terms of engine and its parameters, but with a bar length of 40 cm, called MS 180 16. STIHL mc 180 C-VE chainsaw is a higher class tool. It has a 40 cm long saw blade, easy start system, and quick chain tensioning system. Easier access to the air intake filter, a condition that extends tool life.