How to Clutch a Clutch On a Chainsaw

13th May 2020

Replacing and repairing the clutch on a chainsaw

Chainsaws, for various reasons, need to be repaired from time to time. Of course, you can contact a service workshop or an experienced mechanic. However, many problems can be fixed at home, having only a minimal set of skills and tools.

Answering the question of how to remove the clutch from a chainsaw, we note that this is not a difficult operation, if we strictly adhere to the disassembly technology. Owners of the tool may encounter certain difficulties if the chainsaw has been in operation for a long time, and the clutch parts are attached to each other.

When replacing the clutch, we do not recommend using metal or plastic objects as a stopper. The former may scratch the cylinder, the latter may litter it.

Centrifugal Clutch Chainsaw

We turn on the brake to stop the chain, remove the protective cover and dismantle the saw headset;
We remove dirt, sawdust, dried grease, if any;
Remove the air filter and candlestick;
Using a candle key, unscrew the candle;
Rotating the crankshaft, we bring the piston to the upper point, then we move it by 6-9 mm;
With a rope, with a diameter of 7-8 mm, we stop the piston in the upper position;
Using a special wrench, we unscrew the nut on the clutch.

Most of the moving parts of a chainsaw have a right-handed rotation. Therefore, the left thread is provided in the nut on the clutch. To remove the cover, turn the key clockwise. It is forbidden to carry out this operation with a hammer and a chisel. Knock down the edges!

Clutch Nut Removal

Remove the cover and drive sprocket. We diagnose malfunctions and evaluate the wear of parts. We evaluate the condition of the needle bearing;
If necessary, we replace parts with new ones (most often the leading asterisk needs this);

Installation of the chainsaw clutch system is carried out in the reverse order, however, you should pay attention to some features.

Chainsaw clutch malfunctions are one of the most common breakdowns of this technique.

The question of how to remove the clutch on a chainsaw at home correctly and not harm the tool, is thought not only by inexperienced technicians, but also specialists who have repeatedly repaired it.

In cases where gasoline cutters start to start poorly, instead of starting, slip testing of the clutch for failures is mandatory, recommendations for which will be presented later.

Modern chainsaws are equipped with centrifugal clutches. This means that their work entirely depends on the torque of the motor, which at a particular point in time gives out a saw.

Its main structural elements are:

The principle of operation is as follows. When the saw starts, elements that move freely in the radial direction are pulled by springs to the shaft axis. In this case, the torque does not come to the drum, which means to the sprocket and the guide.

At the moment when the centrifugal force prevails over the power potential of the springs, the clutch elements weaken and contract at the inside of the drum, initiating its torsion. Together with it, the rotational cycle goes to the sprocket and the tire-chain headset itself.

The main advantage of this type of clutch is its slippage during sudden braking of the cutting part, which does not stop the engine. As a result, the “heart” drank. The motors remain intact.

The clutch repair process consists of the following operations:

Dismantle the chain headset, air filter flaps and the clutch itself;
Stop the crankshaft. Just unscrew the ignition section for this;
Unscrew the clutch with a special key with strong movements clockwise or counterclockwise (different saw models can have both left and right threads). Usually, a tool for removing the coupling is included in the completeness of chainsaws;
Proceed to disconnect the drum and sprocket;
If during the inspection of the clutch one or more cracked springs were found (there may be several, for example, Husqvarna chainsaws. 3 units). A new spring must be replaced with a new one;
Assemble the clutch on the chainsaw, put it in place and screw it in. Do not forget that the crankshaft should still be motionless;
To aggregate the removed parts on the saw in the sequence reverse to disassembly;
Lock the clutch. Forward the additional braking handle, start the device and carefully remove it from the inertia brake.

When self-servicing the clutch, you must know that:

Several saws have a washer, which is located between the sprocket and clutch, as well as the sprocket and motor. Consider this when repairing;
The special spring of the oil pump drive must not be damaged during disassembly, and must also be returned to its original position. Otherwise, the chain will be under-greased or will no longer be lubricated.

A tool that has been repaired must pass a check for reliability of bolt ties, lubricant supply to the chain, and the motor is in good condition (it should turn on smoothly and work smoothly). Only then can it be operated.

The owners of chainsaws probably wondered more than once. How to change the clutch on a chainsaw? On most chainsaw models, disassembling and replacing the clutch can easily be done manually by the owner himself; on a small number of models, unscrewing the drum can be done only in the workshop (such chainsaws include, for example, Husqvarna 137 or Partner 351).

Chainsaw clutch disassembly

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.

The disassembly of the clutch for the purpose of removal is carried out in such cases:

When the spring bursts (the chain turns, the engine runs intermittently);
The spring has flown;
A piece of the drum broke off (in this case, noise will be heard, the chain of the chainsaw will also spin);
Temporary wear (it is time to remove and change the clutch due to running out of life).

Modern chainsaws operate on two-stroke engines that are connected by a gearbox to the saw chain. The chain moves along the tire, and according to the centrifugal principle, idling should remain motionless, that is, be safe for someone holding a chainsaw.

If the load exerted on the tool exceeds the recommended, the clutch will weaken or completely stop the transmission of torque to the tire. This will stop the engine.

In the event of such situations, the clutch wears out, so it needs to be replaced over time.

In the operating instructions for the chainsaw, some manufacturers have information that the clutch is a consumable item, that is, is subject to periodic replacement.

In order to remove, disassemble or adjust the clutch, we need such tools:

The scheme of the process of removing the clutch from a chainsaw (for example, take the situation when the replacement of the drum is necessary):

Remove the saw headset using a universal key;
Remove the chain, tire;
Unscrew the air filter cover;
Next, we unwind the candle;
We fix the piston with a stopper or rope;
Remove the clutch with a drift (puller) or a universal key to remove the clutch;
The clutch is removed by unscrewing clockwise;
Remove and replace the drum.

How to adjust the clutch on a chainsaw? It’s more correct to talk about repair, since the carburetor, and not the clutch, is usually subject to adjustment. When we talk about adjusting the coupling, it is important to consider two nuances:

Chainsaws of some models, including German, Finnish, Swedish, have a special washer, it can be located between the motor and the sprocket or between the drum and the sprocket. This washer must be carefully removed and then put back; if replaced, replace with an identical one;
The spring cannot be pulled together; therefore, when it breaks, the part is considered damaged and replaced with a new one. The absence of a working spring will result in a lack of lubricant to the chain.

“In the process of repairing a chainsaw, I had this situation: the clutch did not succumb, did not want to be removed. Jammed, in a word. Such a “grandfather way” helped: the location of the thread was slightly heated by the burner, very carefully so that the oil seal would not be damaged. And it all worked out. Maybe someone will need my advice. ”

Chainsaw clutch replacement. Recommendations and reviews Link to main publication

The chainsaw clutch drum is one of the most common consumables in a chainsaw, because it is it that drives the cutting chain. The drums themselves are divided into two types. With a welded drive sprocket and with a replaceable crown, and in the second case, only a replaceable crown wears out, the drum itself changes much less often.

When repairing the clutch of a chainsaw, we follow the rule. When the two chains are completely worn out, the tire changes, when the two tires wear, the clutch drum changes.

The wear level of the sprocket can be determined without special tools, just inspect it. The chain, moving at high speeds, eventually wipes the teeth along which it moves. If the wear is strong enough, replacing the clutch drum of the chainsaw is inevitable.

The article will talk about the Husqvarna 137 chainsaw. Replacing the clutch drum is a simple procedure and takes place in several stages.

First you need to remove the tire cover and chain brake. To do this, use the combination key that comes with the chainsaw.

Then we remove the air filter cover, unscrew the spark plug, and lock the piston of the Husqvarna 137 chainsaw. It is recommended to use a normal rope for this procedure, since there is a risk of breaking the piston when using a metal stopper.

On the clutch disc itself, the direction for removing it and two holes for the clutch puller are indicated.

Unscrew the clutch clockwise and remove it. There is a clamping washer under the clutch disc, it must also be removed.

Under the clutch drum itself is an oil pump with a washer on which a new drum is mounted.

The chainsaw is assembled in the reverse order, with the exception of tightening the clutch disc. After screwing the clutch onto the thread, it is necessary to re-lock the piston to avoid deformation of the starter group, which is located on the other side of the crankshaft.

Source

Chainsaws chainsaw, clutch