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.
Chainsaw clutch replacement. Recommendations and video reviews
Removing and replacing the clutch with your own hands according to the instructions
Not many sawers know how to remove the clutch on a chainsaw. The design of the mechanisms on different models of chainsaws is different, but the principle of operation is the same everywhere. The dismantling procedure is also almost identical, so further we will consider how to unscrew the clutch on a chainsaw with an internal sprocket.
Initially, you will need to prepare the necessary tools:
- A special wrench called a puller. It often comes with a chainsaw
- Screwdriver for unscrewing the screws holding the protective cover
- Spark plug wrench. used to unscrew the casing and tire mount (included with the tool)
- The rope is for locking the crankshaft. It is better to use asbestos, but any will work for this purpose. The rope is used in case a special locking wrench for the piston is not supplied with the tool
If dismantling is carried out for the purpose of replacement, then accordingly it will be necessary to prepare a new mechanism in advance. When buying a new clutch, you only need to know the exact brand of the chainsaw, since the devices differ in the outer diameter, thread and design of the working mechanism. The instruction on how to remove the clutch on a chainsaw is as follows:
How To Make Your Own Racing Centrifugal Clutch For Free
- First, you need to unscrew the casing and tire fixing nuts
- Remove the cover with the handbrake, as well as the chain and bar
- After that, move on to removing the plastic cover to get to the spark plug. For this, the fasteners are unscrewed with a screwdriver, and the cover is dismantled together with the air filter.
- The spark plug of the chainsaw is unscrewed with a spark plug wrench
- A rope must be inserted into the spark plug hole of the cylinder (install a special key, if available). This is done in order to lock the crankshaft. If the diameter of the rope is several times less than the size of the candle hole, you can make knots on it
- Next, we proceed to unscrewing the coupling itself. To do this, we take a special key, which should be included. If there is no key, then you can use a tool from an angle grinder or make an independent puller, which is also not difficult.
- The splines of the key must be installed in the holes of the coupling, and then proceed to the rotation of the part. It is necessary to rotate in a clockwise direction. Usually manufacturers indicate directions for unscrewing in the form of an arrow.
- When the clutch rotates, the piston will reach top dead center, after which the crankshaft will lock. Then, by applying a little effort, the clutch will break off, followed by unscrewing the mechanism
- The twisted coupling is removed from the chainsaw. If necessary, the drum with an asterisk is also removed.
The procedure is not at all difficult and does not take much time. Assembly is carried out in the reverse order of removal. In order to avoid any malfunctions, it is recommended to install a completely identical clutch on the corresponding tool model.
How to adjust the clutch of a chainsaw?
How is the clutch adjustment on a chainsaw carried out? It is more correct to talk about repairs, since the carburetor is usually subject to adjustment, and not the clutch. When we talk about adjusting the clutch, 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, in case of replacement, replace with an identical one;
- the spring is not subject to contraction, therefore, if it breaks, the part is considered damaged and replaced with a new one. The absence of a working spring will lead to a lack of lubrication on the chain.
How to unscrew the clutch on a chainsaw with your own hands:
How to remove a clutch from a chainsaw: a detailed report
The clutch repair process consists of the following operations:
- dismantle the chain set, air filter flaps and the clutch itself;
- lock the crankshaft. for this it is enough to simply unscrew the ignition cut;
- unscrew the clutch with a special wrench with strong movements clockwise or counterclockwise (different saw models can have both left and right threads). Usually the tool for removing the clutch is included with the chainsaws;
- go to disconnecting the drum and sprocket;
- if, when inspecting the clutch, one or more cracked springs were found (there may be several of them, for example, for Husqvarna chainsaws. 3 units). you need to replace the broken spring with a new one;
- assemble the clutch on the chainsaw, put it in place and screw it in. Remember that the crankshaft must still be stationary;
- mount the removed parts on the saw in the reverse order to disassembly;
- fix the clutch. move the auxiliary brake handle forward, start the device and carefully remove from the inertial brake.
Nuances when installing the clutch system:
- On some chainsaw models, there may be a washer between the drive sprocket and the clutch. Pay attention to which side it faces to the engine;
- Some oil pump drives are equipped with a special spring (whisker), which is responsible for transmitting rotary motion from the drive sprocket to the oil pump. It is important to adjust the spring so that its free end (whisker) falls into the corresponding groove on the sprocket housing. Otherwise, the saw head will not be lubricated;
Important: after dismantling and assembling the clutch, be sure to check the operation of the automatic oil supply system.
“In the process of repairing a chainsaw, I had the following situation: the clutch did not give in at all, did not want to be removed. Jammed, in a word. This “old-fashioned way” helped: the location of the thread was slightly heated with a burner, very carefully so as not to damage the oil seal. And everything worked out. Maybe someone will find my advice useful. “.
When you need to replace the clutch
Removal and replacement of the chainsaw clutch is carried out in the event of a mechanism malfunction. Such malfunctions include:
- Damaged spring. Depending on the model of the tool, the spring can be of two types. coiled (tape or single) or steel plate. The spring is damaged by stretching, disconnection, or mechanical defect. To determine the cause of the malfunction of the entire mechanism, you will need to remove the protective cover and drum
- Drum damage and depletion. Breakage of this part is often associated with chipping off pieces. With such a malfunction, you will need to replace the drum. The inner part of the drum also wears out, so the part also needs to be replaced. If the drum is blue, it means that it has been overheated and should not be used further.
- Development of the mechanism. It is primarily associated with the stretching of the spring, which can be replaced. The threaded connection also wears out. With such a breakdown, you will need to replace the entire clutch.
- Sprocket wear. Depending on the type of sprocket (collapsible or non-collapsible), it is replaced with a drum and, if necessary, a clutch
The service life of the clutch mechanism depends not only on the quality of the components, but also on the correct operation of the tool. To extend the service life of the chainsaw clutch, you need to pay attention to signs that reduce the resource. These features include:
- Frequent seizing or biting of the chain in wood. In such situations, the clutch takes over the entire load, thereby protecting the engine from seizure.
- It is forbidden to increase the speed when the handbrake is on, which also leads to wear of the mechanism due to overheating
- The use of low-quality oil, the wrong choice of tires, chains, etc. All this also affects traction, increasing the load, and thus reducing the service life.
Determining the malfunction of the device is quite simple. To do this, you need to cut the workpiece. If during the sawing process there is a decrease in the speed of rotation of the chain or it stops when the load increases, then it is time to check the grip. How to remove and replace the clutch on a chainsaw, we will consider in detail in the next section.