Do-it-yourself partner 421 chainsaw repair

In detail: do-it-yourself partner 421 chainsaw repair from a real master for the site my.housecope.com.

Summer cottage construction and repairs are not complete without the use of a chainsaw, as is garden maintenance. Due to a malfunction of the tool, all work can get up, so it is so important to be able to disassemble it yourself, find problems and fix them. With enough experience and dexterity, it is even possible to adjust the carburetor of a chainsaw - a complicated procedure, or, more precisely, jewelry. How to carry out the adjustment procedures, we suggest you disassemble today.

Not a single repair event is complete without knowledge of the basics of the mechanism. By understanding the constituent elements and the principle of operation, it is easier to determine the cause of the breakdown.

Any malfunction in the carburetor threatens to stop the engine

The carburetor is one of the main functional parts of the engine, which serves to prepare and supply a fuel mixture consisting of certain proportions of fuel and air. As soon as the proportions are violated, the engine starts to "junk", or even stops working altogether.

You can achieve the correct operation of the carburetor by examining its "stuffing":

Cross-flap tube for air flow regulation.
Diffuser - Constriction to increase the air flow rate, located near the fuel inlet.
Sprayer from which fuel comes (fuel needle in the diagram).
A float chamber that regulates the fuel level at the entrance to the channel.

This is how it looks in the diagram:

The diagram shows the interaction of fuel and air flow

How it works: A jet of air in the diffuser atomizes the fuel, creating a mixture that enters the cylinder. The greater the amount of fuel supplied, the higher the engine speed. Different carburettors work in the same way.

Video (click to play).

Specifically, adjusting the carburetor of a chainsaw is required in rare cases, more often there are problems associated with the flow of fuel or wear of parts. But sometimes the "symptoms" indicate that it is necessary to precisely adjust the mechanism. Here are some signs:

After the engine has started, it immediately stalls. Alternatively, it will not start at all. The reason lies in the excess air and fuel shortage.
Increase in fuel consumption, and as a result - a large amount of exhaust gases. This is due to the reverse process - oversaturation of the mixture with fuel.

The reasons for the adjustment failure can be mechanical:

Strong vibration damages the protective cap, causing all three bolts to lose their position.
Due to wear on the piston part of the engine. In this case, adjusting the carburetor of the chainsaw will only help out for a while, it is better to replace the worn part.
Due to clogging caused by low-quality fuel, scale or damage to the filter. The carburetor requires complete disassembly, flushing and adjustment.

If the chainsaw suddenly stops working, you need to disassemble it to find out the reasons

The carburetor device of models of different brands is almost the same, so let's take the Partner chainsaw as an example. We carefully remove each element and put it in order, so that later it would be easier to assemble.

Chainsaw carburetors from different manufacturers, if they differ, it does not matter

The top cover is removed by loosening three screws. Following it is foam rubber, an integral part of the air filter.

The arrows indicate the bolts that must be unscrewed to remove the cover

Then we remove the fuel hose, followed by the drive rod.

The upper arrow points to the fuel hose, the lower arrow points to the drive rod

Next, remove the tip of the cable.

The arrow shows the end of the cable to be removed.

On the left from the fitting, we pull together the gasoline hose.

We also carefully remove the gasoline hose indicated by the arrow

We finally disconnect the carburetor, it is ready for adjustment. Its mechanism is rather complicated, therefore, if further disassembly of the carburetor is required, the elements should be removed very carefully - they are small, so they can be lost.

The carburetor consists of many small parts, which should be laid out in order during disassembly.

To find out how to adjust the carburetor on a chainsaw, you need to learn to distinguish between three screws (some models have only one).

The L and H screws are similar only in appearance, in fact, they are different

Each screw has its own letter designation:

"L" is for setting low rpm;
"H" is needed to adjust the upper speed;
"T" is needed to adjust idle speed (only one is present on models with one screw).

The factory setting is optimal, and with the help of the screws they adjust the operation of the engine in special situations (work associated with different climatic conditions).

The diagram shows the outputs of the carburetor adjustment screws with the lid closed

A special tool is used to set up the chainsaw.

Adjustment is carried out only with screws L and H. To increase the speed, turn them clockwise. To decrease - counterclockwise. The sequence of using the screws: L - H - T. If you have any doubts about the adjustment, it is better to consult a specialist, since an incorrect adjustment can damage the engine.

For people engaged in construction or logging, as well as living in their own living quarters with an adjacent plot of land, it will be very useful to own a quality Swedish chainsaw "Partner 350", which is an excellent substitute for other tools for cutting wood, for example, two-handed saws or hacksaws ...

Like any other units, chainsaws also require careful maintenance and periodic maintenanceotherwise they will quickly break down as a result of exploitation. At the same time, contacting qualified specialists with a request to fix a chainsaw costs money, which you may not want to spend for any reason, because you understand that you can fix most of the faults and breakdowns yourself. To do this, you need to understand the structure of the chainsaw and watch a video where you will receive detailed instructions for repairing the Partner 350 chainsaw.

The vast majority of product malfunctions occur due to engine problems and related systems. Usually, to repair the unit, it should be disassembled. In order not to make a mistake during the disassembly process, read more about the design of the chainsaw in the video or operating instructions.

When your chainsaw won't start, you should first see if are the candles in good working order, giving a spark, due to which the fuel ignites and by force of an impulse pushes the piston, which does useful work.

In order to assess the condition of the spark plug, you need to remove the wire leading to it from the starter and unscrew it using a suitable key from the groove. Examine the candle: its appearance will tell you what happened to the chainsaw:

Read also: DIY power steering repair

The consequence of such malfunctions is the inability of the fuel to penetrate into the cylinder and begin to carry out useful work on the rotation of the chain, therefore the chainsaw will not start... The reasons for this are as follows:

The fuel filter is out of order because it is clogged.
The breather is clogged (this is the name of the hole made by the manufacturer in the gas tank and designed for air to enter the tank through it).
Lack of fuel in the gas tank.
The diaphragm in the carburetor is not complete, or there is a high probability of blockage in the carburetor passages.
Carburetor adjustment is not correct.

To determine if the breather or filter is clogged with foreign objects, you will need to disconnect from the mountings fuel hose and see if gasoline flows from it and with what pressure. If gasoline comes out slowly and weakly, clean the breather with a thin, sharp object, such as an awl. If the problem is with the filter, remove it from the fuel tank and clean it, and replace if necessary.

Did you find that the carburetor is the root cause of your problems? The good news here is that if your carburetor filter gets clogged, you can easily clean it yourself. In addition, you can easily do the adjustment and tuning of the carburetor of the Partner 350 chainsaw with your own hands, if you strictly adhere to the recommendations from the instruction manual.

The bad news is that with other, more complex carburetor repairs, you are unlikely to cope with your own hands, and you will have to take your unit to the mechanics. Sometimes the manufacturer deliberately does not write in the instructions, how to tune and repair a carburetorso that people who do not understand the device of the product do not try to fix the malfunction on their own if the chainsaw suddenly stops starting and, as a result, does not completely break the unit.

To the main breakdowns of this system chainsaws include:

Low pressure detected by the cylinder compression gauge, which causes the motor to lose power and cannot rotate the chain at the speed needed to cut wood efficiently. The pressure at which the engine runs smoothly is approximately nine atmospheres.
Loss of tightness of the rings in the pistons, due to which hot gases from the cylinders enter the crankcase. The malfunction is eliminated by replacing the rings.
Problems with the tightness of the gaskets located in the cylinder head (cylinder head). Visually expressed in the form of emissions of gasoline combustion products through the slots in the gasket and the pressure drop in the engine. The problem is solved by replacing the gaskets.

If you want to know if there are problems in the cylinders, then the easiest way to do it is remove the muffler and assess the situation, looking through the hole left over from the removed muffler at the insides of the cylinders. In the event of the need for repairs, of course, you will need to remove the cylinder head for open access to the pistons and cylinders.

Sometimes, having accelerated your chainsaw to high engine speeds, you are surprised to find that the engine cannot cope with them, and your tool stalls. At the same time, smoke begins to pour out of the muffler. However, the motor runs easily at low revs.

In this case, there is a high probability that the muffler of your unit clogged with carbon and other products of incomplete combustion of fuel, therefore it must be cleaned. This work is done as follows: you will need to remove the muffler from the chainsaw and disassemble it; then clean its outer and inner surfaces from carbon deposits; in the last step, dry with a hair dryer and place on the chainsaw.

Please note that it is recommended to cover the muffler opening with a plug or rag to avoid clogging the cylinders with debris.

Chainsaws Partner is a great example of truly high quality tools at a low price. The range of chainsaws from Partner is really huge, which allows you to choose a model with suitable characteristics for each interested buyer.

Like other household equipment equipped with an engine, Partner brand chainsaws need to be repaired from time to time. This may be due to improper saw operation, or trivial wear and tear of spare parts.Be that as it may, the chainsaw needs to be repaired, and it is quite possible to do this with your own hands.

As the instructions indicate, for refueling the Partner chainsaw, you should use gasoline, brand not less than AI-92. It must be mixed with 2-stroke engine oil.

The optimal ratio of gasoline to oil for the Partner chainsaw is 50: 1, that is, 20 ml of engine oil should be diluted in 1 liter of gasoline.

If you cannot understand why the Partner chainsaw does not start, then first check the ignition system of your tool. Checking and adjusting the gap looks like this:

First of all, dismantle the cover to which the starter is attached. To do this, we recommend using a T27 hex bit, tools from the chainsaw kit and additional attachments;
Carefully inspect the ignition coil, flywheel with magnets and especially the gap between these parts. To do this, use a specially designed gasket;
Installation of the ignition on the Partner chainsaw is carried out by turning the screws, which brings the coil and the flywheel closer to each other.

It is often required to repair the clutch of the tool in cases where the Partner chainsaw starts and stalls when you press the gas. However, not all novice gardeners know how to remove the leading sprocket from the Partner chainsaw. This can be done in the following order:

First turn the lever and remove the chain brake cover;

Unscrew the nuts securing the clutch system using the wrench supplied with the Partner chainsaw;

Remove the clutch from the chainsaw and disassemble it completely. If necessary, replace worn parts and clean the walls of the standard clutch elements.

If you find that the chain on the Partner chainsaw is not spinning, then the cause of this problem most likely lies in the wear or breakdown of a separate pump designed to pump lubricant onto the chain.
The design of the oil pump includes 2 elements - a storage chamber and a working part. Repair of the pump is carried out with the disassembly of the mechanism, however, it is not recommended to take any action with its working part. Further actions are as follows:

Carefully inspect the inlet and outlet pipes through which the lubricant passes - as a rule, all pump malfunctions are associated with them;
If the channels are clogged, then all the debris must be removed. simultaneously blowing them with compressed air;
If cracks appear on the channels, then they need to be replaced;

If, after assembling the Partner chainsaw, the lubricant again does not pass onto the saw chain, then the pump will need to be completely replaced.

The carburetor setting for Partner chainsaws is slightly different from the procedure for other brands of chainsaws. The difference lies in the markings and the meaning of the adjusting screws. For adjustment, the manufacturer equipped the Partner chainsaw with three screws - the left screw for the amount of fuel, the right screw for the fuel quality and the idle speed adjustment screw "T". All these screws are located on the left under the top cover of the chainsaw body. Adjusting the carburetor of a Partner chainsaw is as follows:

Remove the cover and clean the parts underneath;
Unscrew both screws clockwise to the end, and then turn them 1/5 turn in the opposite direction;
Start turning the number screw slowly until you hear the motor start to run at the maximum speed possible. Immediately thereafter, turn this screw ¼ turn the other way. As a result, the Partner chainsaw must keep idle speed steadily;
Then, using the quality screw, set the maximum speed for the Partner chainsaw.

Each of the available chainsaws produced by the Partner company is suitable for those other purposes.Let's take a look at the specifications and applications of the most popular and common Partner brand models. Image - DIY partner 421 chainsaw repair

The technical characteristics and weight of this model of only 5.5 kg make it easy to use it for removing wet and dry branches at height.

Technical parameters of the Partner 340S chainsaw

Almost every summer resident or villager has a chainsaw in his arsenal, the partner 350 model is especially popular. However, sometimes this tool fails. If you are faced with such a problem, then do not despair, because its mechanism is so simple that you can even do the repair yourself. The article discusses the main causes of breakdowns and their elimination.

This model is in great demand among consumers, but most often it is bought by summer residents to work on their plots. The saw is used not only for harvesting firewood, but also in construction.

In general, the Partner 350 chainsaws are distinguished by their compact dimensions. They are equipped with a sufficiently powerful engine. Their main advantages are - easy start-up and reliable operation, carried out due to a high-quality electronic ignition system and a fuel pump.

It is completely safe to use such a chainsaw. It has a built-in security system that automatically performs overrun brake start for the chain. Its lubrication is carried out in the same mode.

With the launch of the chainsaw, the Partner will not have problems even in winter, since it has fuel primer... The starter drum is equipped with an impeller to help clear dirt. In addition, the manufacturers have supplied the tool with the CCS system. This design traps residual particles, and is also used for long-term use of the air filter.

To increase the service life of the chainsaw on the cylinder of the piston group, the developers made chrome walls... This model also has an ergonomic handle and anti-vibration system.

Chainsaw malfunctions can be conditionally divided into groups:

Malfunctions in the engine (ignition, exhaust and cylinder-piston systems, fuel supply).
Failure of components such as clutch, chain brake, lubrication system or tire.

Chainsaw engine breakdown occurs more often than others. Most of the time is spent on its detection and repair. As a rule, it boils down to such manifestations when the engine is unstable or completely stalls, the engine does not start, does not develop power.

Before you start repairing a chainsaw, first check all possible causes of violations in its functioning, or even better, watch the video. Fortunately, today on the Internet you can find any material of interest.

Then you have to prepare the necessary tools for repairing breakdowns:

device diagram (should be included in the delivery set);
keys, including spark plugs.

When the engine refuses to work, but at the same time there is a spark on the spark plug, and fuel is supplied, check the ignition.

It is not at all difficult to check it: unscrew the candle, and adjust the gap between the contacts, connect it to the wire and press it against the cylinder body. After that, watch for a spark.

If any deviations occur, you need to perform tuning the ignition system... In general, this process is similar to adjusting the ignition in other two-stroke engines.

To establish a similar malfunction of the chainsaw, it will turn out when inspecting the spark plug. Fuel may not flow into the cylinder for various reasons:

The fuel filter in the tank is heavily clogged.
The hole in the tank cap is clogged, preventing the gas from flowing out.
There is little or no fuel coming out of the carburetor.

In the event that there is no correct ratio between the gasoline and the air mixing in the carburetor, or there is insufficient fuel flow, check that the channels and the air filter of the carburetor are not clogged. In addition, it may need to be adjusted.

The filter is carefully removed before cleaning and washed with detergent, after which it is left to dry. Then it is put in place.

Carburetor adjustment carried out, as a rule, with screws - maximum and minimum revolutions. When carrying out it, you must strictly follow the instructions for repairing a chainsaw, otherwise you can damage the engine. Sometimes manufacturers leave only one adjustment screw to prevent inexperienced craftsmen from interfering with the carburetor.

If debugging didn't fix anything, then it's worth doing cleaning of channels and filter mesh, and also check the integrity of the membrane.

Do not forget that a carburetor is one of the complex mechanisms of a chainsaw, so you need to approach it responsibly when cleaning and disassembling it.

It consists of many small elements that can pop out unnoticed and it will be difficult to find them. Often after disassembling this device, some users cannot reassemble it.

If the chainsaw engine functions normally at low speeds, but at high speeds it smokes and stalls, then the reason is most likely in the muffler. Dismantle it first, but remember to close the outlet.

Then disassemble and clean off carbon deposits dry method or detergents, dry with a hairdryer, assemble and install.

Do not dry clean without special protective equipment, as carcinogens in the soot are released as dust. It is very dangerous to inhale it. When operating a chainsaw, it is necessary to monitor the quality of the fuel mixture.

Need to lubricate the chain regularly during the saw operation, because it works in extremely difficult conditions. Its service life is negatively affected by abrasive particles, dust and even overheating.

If you leave the chain dry, it will soon happen. pulling and overheating... In the worst case, jamming can occur, that is, the sprocket breaks off. Oil is supplied through it through channels, which are quite often clogged with sawdust. They should also be cleaned regularly.

In addition, constantly clean under the cover of the chainsaw from debris and sawdust, as this may not apply the chain brake. In addition, dirt has a bad effect on the performance of the device.

The most serious malfunctions are considered scratches on the surface of the piston and cylinder, their damage, sinking of the piston rings in the grooves, breakdown of the crankshaft bearings.

Most of them lead to the inability to start the engine, since pressure in the cylinder drops... There are several options for repairing and checking the condition of the cylinder-piston group (CPG).

For example, you can measure the compression in the engine... For this operation, a compression gauge is used, which is mounted in the spark plug hole. Thus, the condition of the parts of the CPG can be checked.

To view the side of a cylinder, it is necessary to remove the muffler and look into the opened gap. Although review is limited, the general condition of CPH can be seen.

For an accurate assessment of the performance of the cylinder-piston group, you will have to completely disassemble the engine chainsaws. First, the crankcase is disconnected from the cylinder, after which the piston is pulled out. If it has chips, scuffs and large scratches, then it needs to be changed.

Low compression occurs most often when coking and damage to the piston ring. Be sure to check that there is no carbon deposits on it. In addition, it should sit freely in the piston groove and be pressed against the cylinder surface.

In general, you always need keep your chainsaw clean and different holes. This is the only way to avoid many breakdowns and further repairs. Be sure to watch the video on how to do it correctly.

Chainsaw Partner 350 S - features, troubleshooting, operating instructionsOne of the most popular household chainsaws in Russia is the 350th model of the Partner saw.This can be explained by a number of advantages of this model.The most important qualities of such saws, which characterize them on the positive side:

compactness and light weight with sufficient power;

relatively affordable price;

durability;

excellent repair facilities.

Many sources claim that it was this Swedish company that produced the first mass-produced household chainsaws in Europe. And it happened in 1949.It is generally accepted that these are good Chinese saws, and this is partly true - most of the Partner chainsaws sold in our market are assembled in China, which is honestly written on their nameplates. But besides China, saws of this brand are also produced in America, Italy, Norway and England, and you can also buy them in Russia.For more than 10 years, this brand has been owned by the Husqvarna concern, one of the leading manufacturers in this segment, which affects not only the design features of the saw, but also the widest network of service centers that can quickly and efficiently service it.Few people know, but for the first time the chain brake of chainsaws and the heating system of the handles were applied precisely on Partner chainsaws, so they should not be underestimated.There are about 30 modifications of this brand's chainsaws. From the smallest Partner 340S saw on the market today with 1.44 kW of power at 13,500 rpm, to the most powerful Partner 842 with 1.6 kW at 12,000 rpm.But, perhaps, the 350th model remains the most bought in Russia.We will consider it in more detail.Specifications:

power 1.52 kW;

working volume 36 cm3;

idle speed 3000 rpm;

the maximum recommended speed is 13000 rpm;

saw bar length 40 cm;

chain pitch 3/8 ".

It is possible to use saw bars with a length of 45 cm, but for this length the saw is still rather weak.The saw is equipped with a hand chain brake, an easy start system, a primer for pumping fuel, a carburetor air damper regulator, chrome-plated cylinder walls and a cyclotron air preparation system. It is assembled quite well and, yielding in class to more eminent classmates from Husqvarna and Shtil, surpasses almost all other chainsaws in the household segment in its consumer characteristics.One of the main features of this saw, its users note the durability of operation with a minimum number of failures. And yet they do happen. To determine why the saw stopped working, you need to make elementary diagnostics.If the saw does not start, then:

there is no spark on the candle;

no fuel is supplied;

no air coming in.

First, check for a spark: by unscrewing the spark plug, connecting it to the high-voltage wire and placing it on the cylinder, pull the starter. If there is a spark, then clean and adjust the spark plug gap (0.5 - 0.65 mm). If it is not there, then you need to change: either the flywheel or the coil (magneto). In addition, the candle itself may fail or the high-voltage wire may break.The next step is to check the fuel supply. To do this, disconnect the feed hose from the carburetor and check for its presence. Absence may mean that the fuel filter or supply system is clogged. And the carburetor itself can also become clogged.If you have no experience in repairing and cleaning it, entrust this work to specialists.If the air supply deteriorates, the saw should start, but it will not perform well. Remove and wash the air filter. Put it back in place only after it is completely dry.If the saw starts well, runs at idle speed and stalls when gas is supplied - the muffler is most likely clogged. Take off, disassemble, wash, put in place and work on.

Read also: DIY repair nissan murano z51

You can also easily change the bar and chain, carburetor, starter, oil pump, ignition and clutch with your own hands.Here is a video of the complete disassembly of this saw:

In order to simplify the diagnosis of malfunctions, it is customary to distinguish them into two main categories:

engine malfunctions;
malfunctions of other parts of the chainsaw.

Most often, failures occur in the engine systems, however, the rest of the tool, due to intensive use or improper care, can fail at any time. How to determine exactly where the breakdown occurred? Simple logic will help us with this.

If the problem is in the engine, it will:

do not start;
deafen;
work unstable;
overheat;
smoke;
develop insufficient power.

As for all other malfunctions, as a rule, they manifest themselves with a normally operating motor.

If your chainsaw won't start, the first thing to do is to check for a mixture of fuel in the tank. By the way, it must be prepared in the proportions indicated by the engine manufacturer, otherwise the instrument will simply not start.

After verifying that the fuel mixture is correct and available, the ignition system should be checked. To do this, you need to inspect the spark plug.

Her condition can say a lot:

indicates that the fuel mixture does not enter the carburetor, which means that the problem is not in the ignition;

fuel-splattered candle

is the result of an overabundance of the fuel mixture, which lies either in a violation of the engine starting algorithm, or in an incorrect carburetor adjustment;

this is a signal about the presence of low-quality oil in the engine lubrication system, incorrect carburetor settings, or an incorrectly prepared fuel mixture.

If the spark plug is splashed with fuel, wipe it thoroughly after removing it. The fuel supply system should also be cleaned. To do this, it overlaps, after which the starter is turned on. A carbonized candle must be carefully cleaned with an awl and emery.

When checking the spark plugs, you should pay attention to the distance between the electrodes (the normal gap is 0.5-0.65 mm), as well as the condition of the gasket and the presence of a spark. A damaged or worn gasket will have to be replaced, and the spark can be checked by putting on the ignition cable, connecting the cylinder and plug nut, and starting the starter.

If the discharge does not occur, the plug must be replaced. In the event that a spark does not appear with a new candle, then the problem is in the connection to the high-voltage wire or in it itself.