How to remove the sprocket from a Partner chain saw

Types of driving sprockets

There are two types of drums, depending on the purpose of the chainsaw, professional and domestic. The frequency of sprocket replacement depends on this: if a home saw is used much less frequently than a professional saw, then consumables such as a sprocket, bearings or a roller need to be replaced less often, too.

There are two types of drive sprockets by design:

Solid or non-separable. As the name suggests, this is a single construction where the clutch plate and drive ring are firmly welded or pressed together. If necessary, the entire part is replaced.

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

Replacement ring on right side of clutch drum.

Once you’ve determined what type of saw and sprocket you need to replace, you can begin the process of refurbishing the mechanism.

DIY How To Remove Chainsaw Clutch without Specialty Tools. Saw Repair. Poulan Husqvarna Stihl Echo

Design features

STIHL professional chainsaws

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

Accordingly, their drive pinion will be different, as well as the sequence. This is a characteristic of chainsaw gear units. With most professional tools, the bar can change its position on the saw in two planes.

Major chainsaw malfunctions and troubleshooting steps, described here.

Replacement of Worn Parts

If the gear has a replacement crown, the condition of the base should be carefully checked. If you notice any dents, chips, deep scratches, changes in geometry or corrosion you should replace not only the gear teeth but also the whole part. Worn and new parts working together in the same assembly will shorten the life of the entire assembly. The risk of the chain jamming or breaking substantially increases.

In addition, the vibration load on the clutch, transmission and engine of the device will increase. The same considerations apply when using the same chain over a long period of time.

Folks “craftsmen” sometimes reanimate the stretched chainrings, simply throwing out one or more links and re-pressing the axle. In this case the chainsaw needs a sprocket replacement.

You should also not change the diameter of the gears (and therefore the number of teeth). Operating with a larger or smaller sprocket produces forces in the transmission and engine for which the designers of the machine had not intended. This will reduce the service life of the tool and will not increase productivity.

Despite the chainsaw’s safety features that immediately stop the chain saw in case of a guide bar break or chain break and protect it from flying off, it is better not to allow such situations. The need for a replacement sprocket is only reinforced by safety concerns.

How to remove the drive sprocket from a Husqvarna, Partner, STIHL, Champion chainsaw

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

If you are replacing a chain sprocket, be sure to do so with care and attention to detail.

The design of the device chain saw is a classic mechanism that is powered by an internal combustion engine. The unit is designed with one of the simplest single-cylinder, two-stroke carburetor engines that run on gasoline. the saw’s simple design and straightforward construction is a guarantee of trouble-free and dependable operation in tough application conditions. Operating a chainsaw does not require much knowledge or skill on the part of the operator. The only prerequisite for long and trouble-free use is regular inspection and maintenance of the device. Wear components should be replaced regularly while the machine is in operation. To reduce wear on the tool, check the chain lubrication, chain tension, chain wear, and drive sprocket.

Before you repair your chain saw, you should understand the design of your chain saw. To replace one of the main elements of the structure of the device. the drive sprocket. it is necessary to study the mechanism of the unit’s clutch.

How to remove the sprocket from a chainsaw detailed description

Most STIHL, Partner, Husqvarna and other brands of chainsaws use a centrifugal clutch. When the engine gains a certain number of revolutions, it engages automatically, transmitting rotational motion to the sprocket.

the clutch is a disc in the drum. The whole unit is fixed on the chainsaw engine shaft. In its normal state, the clutch springs press the friction linings, preventing motion from being transmitted to the drum, and therefore to the sprocket. When the speed reaches a certain value, centrifugal force is created and the elements with friction pads move, exerting pressure on the internal drum walls. The chain sprocket is driven in this way, turning the saw chain.

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

The way for a sprocket with a stationary ring

• Disassembly of the cover plate and guide bar;
• locking the piston part of the motor;
• disconnecting the clutch from the engine system;
• Removal of the clutch clutch and centrifugal sprocket from the saw body;
• Visually inspect the sprocket and its toothed part;
• if defective, replace the sprocket with a new clutch drum;
• Diagnosis of chainsaw clutch elements for defects. worn centrifugal springs and cams can adversely affect the operation of the sprocket;
• if there are no faults, move on to the assembly stage. To do this: remove the stopper;
• pull back the ignition cable;
• screw a stopper to fix it on the motor shaft of the centrifugal mechanism;
• Using a universal wrench against the direction of the chain, clamp the clutch;
• return the remaining removed parts to their original positions.

The method for a star with a collapsible clutch drum

The second method on how to unscrew the sprocket on a chainsaw with a collapsible clutch drum looks more simplified compared to the previous. The process is similar, but it will be disassembled and reinstalled not the whole star, but only a separate part of it: the ring gear. It should not be forgotten that installing a new chain on the chain saw bar is one of the reasons for reequipping the saw with a new sprocket. Otherwise the chain will be lengthened prematurely or will break while you are working. Less wear on the clutch drum gives the alternate use of several chains and periodic maintenance of its bearing. This chainring works only when idling: it doesn’t work when revs are higher. We recommend to change it together with chain and sprocket and to lubricate it with chain oil.

How to remove the chain sprocket on a chainsaw

You can remove and replace the sprocket at home, without having to use a service center. The procedure is as follows:

• unscrew the saw headset fastener with a special wrench;
• unscrew and remove the chain cover;
• unscrew and remove the air filter cover and the filter;
• unscrewing the spark plug.

To remove the sprocket, you need to fix the engine piston. To do this, pull the kickstarter cord gently, pulling the piston up, but not all the way out. In the spark plug hole, push a long piece of thick cord until the space in the combustion chamber is filled. This is needed to prevent the piston from crossing the top dead center. The cord will at the same time act as a damper, protecting the piston from possible damage. Some of the cord should come out of the hole so you can pull it out later.

To unscrew the sprocket you need a special wrench, which is rarely included with saws, especially the cheaper models. Use a tapping block made of soft metal like copper or aluminum.

Use the pickaxe against the cams of the centrifugal mechanism and hit it lightly with a hammer. The direction of impact should be nearly parallel to the plane of the clutch, because a larger angle can bend the cam mount and the clutch will have to be replaced. Direction of impact. counterclockwise. The clutch is often marked off and has an arrow showing the direction of impact.

Do not use steel knockers or a chisel, as there is a high risk of damaging the clutch.

After unscrewing the nut, it can be unscrewed by hand.

Some saw manufacturers use simple left-hand thread nuts to mount the clutch and sprocket. Then the task becomes easier, because a simple open-ended wrench of the right size can be used for removal.

Now remove the drive sprocket, taking care not to lose the plastic pinion oil pump drive and needle bearing.

How to install

After all the work is done, the sprocket can be replaced with a serviceable one. Reassemble in reverse order. It is advisable to additionally lubricate the needle bearing.

It is not necessary to unduly tighten the nut, since it will tighten during operation.

How to remove and replace the chain saw sprocket?

Many gasoline chainsaw owners worried about how to remove a chainsaw sprocket after the device has broken.

When replacing a chain saw sprocket, it must be handled with care and attention.

The chainsaw is designed as a classic mechanism that is powered by an internal combustion engine. The saw has one of the simplest single-cylinder, two-stroke carburetor engines that run on gasoline. The simplicity of the engine and the chainsaw’s overall design is essential for the chain saw’s trouble-free, dependable operation in harsh conditions. The chainsaw does not require much knowledge or skill on the part of the operator. The only prerequisite for long and trouble-free use is regular inspection and maintenance of the device. In the process of working with the device, it is required to regularly carry out the replacement of wear and tear nodes. In order to reduce tool wear, you should check the chain‘s lubrication, tensioning, wear rate of the chain and wear rate of the drive sprocket.

Before carrying out the repair of a chainsaw, you should study its design. To implement the replacement of one of the main elements of the design of the device leading sprocket requires to study the mechanism of the unit clutch.

How a chainsaw clutch works

On chainsaws Husqvarna, STIHL, Partner and most models of other well-known brands, a centrifugal type clutch is installed. It is automatically engaged when the engine reaches a certain speed.

the clutch housing is in the shape of a disk. It has movable friction pads that can move in a radial direction. They are normally pressed against the center by the built-in springs and do not touch the chain drive sprocket drum.

When the engine reaches a normal RPM of the shaft to which the clutch basket is attached, centrifugal forces are generated which exceed the force of the springs. The elements with the friction pads move to the sides, pressing against the inner surfaces of the sprocket drum which begins to rotate at the necessary frequency. Such a system can protect the engine from serious damage if the chain jams.

Depending on the model, the sprocket is located outside or inside the clutch unit. For safety purposes, this entire assembly, with part of the guide bar, is covered with a protective cover.