Ignition of the Friendship chainsaw - from device to rework

Homemade products from “Friendship-4”

The layout of the engine and gearbox of this saw is so successful, and the clutch is so compact that the device is an almost ready-made power unit for many interesting homemade products.
In 1973, based on these engines, the MAI X-3 ultra-light helicopter was created, followed by modifications 4 and 5. They were even shown at a number of exhibitions, but did not go into mass production. It was too difficult to coordinate the operation of as many as 8 engines for 2 propellers that ensured its movement.

But he flew! But driving the engine from Druzhba is much easier. On snow and on hard roads.

True, sufficiently high speeds at the output gearbox of the saw require the installation of a large driven gear on the traction wheel, an intermediate reduction shaft, or a reduction in the diameter of the wheel itself.

But snowplows and motor cultivators from it turn out to be quite productive, but also with a system that reduces the speed.

Finally, it is worth remembering that the saw is equipped with a system with a hydraulic wedge.

This device is a great help when felling trees. How it works will become clear after watching the video:

Dear readers, if you have any questions, please ask them using the form below. We will be glad to communicate with you

The production of Druzhba chainsaws began in the USSR in 1955 at two factories - ZiD (Dzerzhinsky plant) in Perm and Sibpribormash in Biysk. At the time of its launch, it was one of the most successful designs of a hand chainsaw. Therefore, in 1958, Friendship was awarded a Gold Medal at an international exhibition in Brussels.

How to adjust the carburetor on a Druzhba-4 chainsaw

Adjusting the carburetor of the Druzhba-4 chainsaw is required when the engine starts to work incorrectly - it stalls at idle, does not pick up speed when gas is applied, and “fails.”

To access the adjusting screws of the KMP-100 carburetor, you do not need to remove the housing cover; they are always open and accessible. There are no screw markings on the carburetor body, like on modern chainsaws. The first screw, which is located closer to the cylinder, regulates the fuel supply at low and medium speeds. The second screw is the main screw, it regulates the fuel supply at maximum speed

Required Tools

A screwdriver (minus) is required for operation. If desired, you can use an electronic tachometer. It will show the number of revolutions before and after adjustment.

General adjustment algorithm

The carburetor is adjusted in different ways. The simplest and most effective is ongoing adjustment during operation.

Lots of gasoline - spin

• The engine is warmed up for 5-10 minutes.
• If in the “full throttle” mode the engine operates as if idling (does not develop speed due to excess gasoline in the fuel-air mixture), the second (farthest from the cylinder) screw is tightened clockwise 1/4 turn.
• If the engine begins to work better, tighten it another 1/4 turn. If the engine starts to stall when the gas is fully applied, the screw is unscrewed back.

Low on gasoline - unscrew

If the engine stalls in the “full throttle” mode (there is not enough gasoline in the fuel-air mixture), the adjustment begins by unscrewing the second screw by 1/4 turn and testing the operation of the engine. If it gets better, unscrew it some more until the engine begins to “choke” and run as if idling at full throttle. Then the screw is tightened back.

After adjusting the second screw, check how the engine operates in the transition from idle to medium and maximum speed. If there are dips, unscrew the first screw 1/4 turn and test changes in engine operation.

As a result, the optimal operating mode of the engine is found through such trial regulation.

Adjusting the idle speed on the Druzhba-4 chainsaw is done using a screw located on the gas handle. Its position determines how far the throttle valve in the carburetor is open at idle.

Idle speed is adjusted based on two requirements:

1. The engine should not stall.
2. The chain should not spin.

Adjustment in a different sequence is possible. The screws are first tightened to the end, then unscrewed by 0.5 - 3 turns (different sources indicate different numbers of turns).

The video shows a simple and understandable process for adjusting the KMP-100 carburetor on the Druzhba-4 chainsaw from the screws position “tightened completely and then turned out”:

For beginners, we recommend watching a more detailed video about adjusting the KMP-100U carburetor of the Druzhba-4 chainsaw. The author of the video tells everything that is useful and everything you need to know. Just a whole step-by-step guide from A to Z.

Step-by-step algorithm

1. Unscrew the fastening screw.
2. Remove the fuel hose.
3. Unscrew the top damper cover.
4. We remove the carburetor.
5. Remove the membrane cover to adjust the level. You need to unscrew 6 screws in a circle.
6. Let's half the body and assess the condition of the membrane, it must be intact - this is the main thing, cracks, scuffs, and tears are not allowed.
7. We evaluate the performance of the mechanism responsible for the operation of the valve.
8. We blow through all the holes and clear out any debris if there is any.
9. We set the level by adjusting the height of the tongue; it should be on the same edge as the body.
10. If everything is done correctly, then by applying, for example, a ruler, you will see that the tongue and the edges of the body are on the same level.
11. We unscrew the screw with the needle from the central jet and assess its condition, clean everything from dirt, if there is any, blow it out in any case. The screw located above, also visible in the photo, is responsible for idle speed; it also needs to be unscrewed, the condition assessed and blown out with air.
12. This completes the cleaning, put everything back together in the reverse order and put the carburetor back on the chainsaw.
13. Don't forget to replace the air filter and pump up the fuel before starting.
14. Let's try to start the chainsaw.

Possible nuances and problems

In any case, when tightening the screws all the way, you need to remember the number of turns made for each screw. This will make it possible to return to the original adjustment if suddenly the chainsaw, adjusted according to the recommendations, does not start at all.

Operation, maintenance and repair

To ensure trouble-free operation of the saw, it must be adjusted periodically. The operating instructions supplied with the equipment describe the features of setting up the model. Incorrect configuration will lead to unbalanced operation of the nodes.

How to adjust the carburetor

Failures occur when not enough or too much fuel is supplied, as well as if the proportions when mixing fuel with air are violated.

Carburetor adjustment is carried out as follows:

1. The fuel regulating screw is first turned all the way, and then back (counterclockwise) 1.5-2 turns.
2. Start the engine, warm it up for 1-2 minutes and turn the T screw in one direction or another to ensure its stable operation at maximum speed. The chain should not move along the bar at idle speed.
3. Check and, if necessary, seal the connection between the carburetor and the cylinder.

It is easier to adjust the carburetor using a tachometer, but at home, in most cases, engine operation is adjusted by ear. When both the quantitative and qualitative fuel supply is normal, the engine does not overheat, does not choke, runs smoothly, without sharp sounds. When adjusting, turn the screws slowly, without jerking.

How to set the ignition

Stable operation of the engine is ensured by correctly adjusted ignition - the Druzhba 4 chainsaw in this case will consume a minimum amount of fuel. The saw is ignited thanks to a magneto using a spark plug and a special wire.

To monitor the quality of the spark for igniting the chainsaw, place the spark plug on the cylinder body and pull the starter. If the spark plug is in working condition, a spark will jump between the electrodes. A weak spark will not ignite the fuel; such a spark plug must be replaced.

It is better to replace the contact ignition of a chainsaw with an electronic one. This will eliminate constant problems with its regulation. It is necessary to ensure that the ignition coil mounting screws do not loosen.

Basic malfunctions and their elimination

If you know why the tool malfunctions, you can repair it yourself at home.

When the Druzhba 4 chainsaw engine starts and stalls, the reasons may be as follows:

1. There is not enough fuel in the gas tank. It is necessary to add the mixture according to the instructions supplied with the instrument.
2. The spark plug was splashed with fuel. This prevents a spark from forming. The candle must be removed, dried, and heated on a gas burner.
3. Poor contact between spark plugs and wire. This occurs due to the increased gap (more than 0.5 mm) between the tip of the spark plug and the wire. The spark plugs must be cleaned of carbon deposits with a wire brush and blown with air. They need to be changed periodically.

If engine malfunctions occur at idle, repairing the Druzhba 4 chainsaw comes down to the following:

• replacing the fuel mixture with reducing the amount of oil;
• cleaning the air filter and muffler (due to its clogging, the engine runs but does not develop speed);
• checking the fuel line and replacing the tube if necessary.

If the cutting speed has decreased and the tire is “driving”, pay attention to the sharpness of the saw teeth. A well-sharpened chain is more important than a strong engine. It is best to take it to a master for sharpening or use a machine with a rotary sharpening disk. The bevel of the Friendship saw blade on the bottom edge is 45°, and on the side edge - 60°. The height of the limiting protrusions relative to the chain teeth should be the same and checked after 3-4 sharpenings of the chain.

It is recommended to place the chain in liquid lubricant for some time, preferably heated.

The reasons why the Friendship saw does not start may be the following:

1. The fuel mixture does not comply with the repair and operating instructions for the model.
2. Manufacturing defects. Repairs are carried out in a warranty workshop.

When assembling, even if the parts fit tightly, you should not use force, for example, hitting them with a hammer. By replacing worn elements, you can restore the functionality of the chainsaw or extend its life.

Remaking the ignition of the Druzhba chainsaw

Since the engines on the Druzhba 4A and Druzhba 4A Electron chainsaw models are absolutely identical, the interchangeability of contact and electronic ignition systems on all models is quite possible.

Moreover, it is sometimes possible to remake a failed coil of an old contact ignition and install it instead of a failed electronic version.

Reworking the contact ignition coil

The coil is removed and all the high-voltage secondary winding made of the thinnest wire that has become unusable is removed. The primary winding, consisting of several turns of powerful wire, almost never fails. She is left in place.

Instead of the removed winding, they use an external high-voltage coil (bobbin) from a motorcycle, a two-speed moped of the Soviet period, or a car. The coil is attached in any way in a convenient place. Restore the connection diagram to the same as it was with a stationary winding:

• from the primary winding of the coil to the + (plus) contact on the bobbin;
• from the contact - (minus) on the bobbin to ground (engine housing).

The disadvantage of this option is that an additional part will appear on the body of the Druzhba chainsaw.

The advantage is that high-voltage coils are easy to change and are available.

You can also find descriptions online of how to repair the electronic ignition system of Friendship, which is reasonably considered to be practically unrepairable. This option is also possible, but for this you need to be an experienced specialist in the field of electronics and electrical engineering.

The ignition device on the Druzhba chainsaw is described in the following video, which also provides recommendations for adjustment:

For residents of the USSR, Druzhba was the only chainsaw, always in short supply, but relatively affordable. (Ural was created on the basis of Druzhba as a more powerful option for the timber industry). Hundreds of thousands of Friendships have been issued over decades. Many of them, due to their good maintainability, are still in working order. And spare parts, including two types of ignition systems, can still be found at flea markets and even online at sites like Avito.

Intended mainly for work in logging sites and sawing logs obtained in this way, the Druzhba chainsaw is also indispensable in private households for solving many everyday problems. Not expensive, very easy to operate and repair, successful in technical terms - the Druzhba chainsaw has been conscientiously and effectively serving for more than 50 years, first to citizens of the USSR, and now to Russians. The range of prices for their acquisition is currently wide. In new condition (mothballed), depending on the modification, their cost ranges from 8 thousand rubles. up to 15 thousand rubles, and used ones, depending on the actual condition - from 1 thousand rubles. up to 7 thousand rubles

Review of Druzhba brand chainsaws

The first model of the Druzhba chainsaw was developed in 1953 and released in 1955. They were produced at machine-building plants in the cities of Biysk and Perm. All models of these chainsaws have a two-stroke, single-cylinder, air-cooled engine with a carburetor. Thanks to its convenient design and high performance, Druzhba is still in demand, and saws of the first models are also in working condition. The main purpose of the Druzhba chainsaw is felling forests and sawing logs.

Before operating any chainsaw, be sure to read the manufacturer’s instructions and follow all safety rules.

User manual

Before you start working with the Druzhba chainsaw, you must study the operating instructions. After reading it, you can find out that at the first stage you should adjust the saw set, otherwise the clutch of the device will fly out. During the first 45 minutes, you need to operate the chainsaw at low speed. This will correspond to the output of the fuel tank. The engine is then turned off and the chain tension is checked. Then you can make several cuts using little effort. Only then can you proceed to active operation. These recommendations are relevant due to the fact that the chain, bar and sprocket must warm up well, while the oil will fall on the lubricated parts of the headset.

As for gasoline for the Druzhba chainsaw, strict proportions must be observed. The ratio of oil and gasoline should be 1 to 50. This indicates that 5 liters of gasoline will be needed per 100 ml of oil. In order to prevent engine failure, unleaded gasoline should be used. The octane number must be at least 90. The fuel mixture can be stored for 1.5 months, because otherwise it will oxidize and become unusable.

Repair Tips

Thanks to its simple design, you can repair the Druzhba chainsaw yourself.
For example, saws of this brand often have problems with ignition, especially if a contact one is installed. It is extremely sensitive to various oils and gasoline. Therefore, it is better to purchase electronic ignition instead. Moreover, contact spare parts for the friendship chainsaw are expensive and irreplaceable. If the spark plugs are heavily flooded, you should pay attention to the carburetor. In this case, it is necessary to bend the gasoline valve slightly inward; as a result, the amount of fuel supplied will decrease and the spark plugs will stop getting wet.

The carburetor is also easy to adjust:

1. The fuel screw is screwed in completely and unscrewed back 3 turns.
2. Close the propeller completely and turn it back 2 turns.

To prevent air from being sucked into the system from the outside, all seals must be tight.

Compared to other models, the Druzhba chainsaw is sold at a lower price due to the small number of functions, but has excellent quality and a long service life, which imported models cannot boast of.

Operating instructions for the “Druzhba” petrol saw

This document contains the following information:

1. Device, assembly diagram of the Druzhba chain saw.
2. Technical characteristics of a gas-powered saw.
3. Safety precautions when operating and servicing a chain saw.
4. Preparing for launch.
5. Run-in.
6. Maintenance of the Druzhba chain saw.
7. Malfunctions of the Druzhba chainsaw.

Let's briefly go through the sections:

Chainsaw safety

• do not operate the saw with the air filter removed;
• hold the instrument with both hands;
• use special clothing and protective equipment;
• do not adjust the carburetor if you lack the skills;
• use only high-quality mixture;
• do not work with an empty oil tank;
• do not operate the saw if it is faulty;
• ensure the absence of strangers in the workplace;
• take 10-minute breaks every 45 minutes of work;
• do not use pure gasoline, only when mixing gasoline and oil;
• When replacing the headset, turn off the saw motor.

Repair and modernization of Druzhba saws

Although these saws stopped being produced at the turn of the millennium, a huge number of them are still in use and sold on the Internet. Some are far from exhausting their resources. But even those that have lost their appearance and acquired problems in their work are easily restored.

After all, the body parts of these saws practically do not wear out, and the rest must be replaced. The video will help you avoid difficulties when disassembling “Friendship-4”:

Most often, during repairs it is necessary to change the crankshaft bearings, all seals and gaskets.

It will not be superfluous to replace the piston rings during disassembly. It is also possible to install a repair size for the piston group.

If your chainsaw has a gearbox without lubrication, then it is worth installing a more modern one. This will extend the life of the saw chain.

And here is a video of the device of such a gearbox, which shows how it differs from the standard one:

Such a new one from Ural costs about 3.5 thousand rubles, but with the cost of a slightly used Druzhba being 4 - 5 thousand rubles. this price may seem excessive. The same applies to other elements. So, if your contact ignition is working, then trade it for a new one or install an electronic one for 500 - 600 rubles. maybe it's not worth it. After all, the main problems with it arise due to damage to the crankshaft oil seal, and when replacing it, everything can return to normal.

A removable starter costs the same amount, so it’s better not to lose it. Some fasten it rigidly with self-tapping screws in a regular place and put up with certain inconveniences in work, and some fix it on a cable and find a place for it on the handle of the chainsaw.

It is cheaper to repair a carburetor using a repair kit.

The cost of a new one is about 1 thousand rubles.

The biggest modifications are most often made to the ignition system, namely: installing a car coil to replace the secondary winding of the standard coil. How to do this correctly is shown in the video:

At the same time, the spark becomes much more powerful, and problems with starting the saw are eliminated, especially in winter.

The chainsaw clutch practically does not fail, but sometimes requires minor repairs. It is designed in such a way that at low speeds the L-shaped profile does not unclench and the gearbox does not engage, but if the rivets on which it is attached become loose, then it can touch the outer part of the gearbox coupling at low speeds, then the clutch “drives.” It's worth trying to rivet them harder. And if the reason does not go away, then in this case buy a new clutch.

Characteristics

Over the 60 years of production, the design of the Druzhba chainsaw and its characteristics have changed insignificantly.

The general parameters are:

• weight when fully equipped - 12.5 kg;
• dimensions - 865x460x500 mm;
• saw bar length - 450 mm;
• The fuel tank capacity is designed for 1.5 liters of fuel liquid;
• spark plug - any with a diameter of 17 mm.

The main difference between the modifications is power. It is indicated by the number in horsepower at the end of the model names.

Friendship 2

The technical characteristics of this model are as follows:

• engine power - 2.2 kW;
• saw starting type - manual;
• lack of a rotary gearbox.

What makes Druzhba 2 different from the first model is the presence of a device for braking the chain, which made it safer: the tool cannot accidentally injure the worker or the people around him. The material from which the case is made is reliable and can withstand any temperature changes.

Friendship 4

This model received a gold medal at the World Technology Exhibition in Brussels in 1958.

The technical characteristics of the chainsaw are as follows:

• power - 2.94 kW;
• engine oil tank volume - 150 ml;
• total shaft rotation speed - 5000-5400 rpm;

A gas-powered saw can cut through a trunk with a diameter of up to 50 cm in 1 minute.

Friendship 4M electron

The Druzhba 4M electron chainsaw is distinguished by the fact that this model is equipped with an electronic non-contact ignition system, which significantly increases the reliability of the engine.

The technical characteristics of 4M are as follows:

• power - 3 kW;
• fuel consumption - 720 g/kW h;
• the distance between the spark plug electrodes is within 0.6-0.7 mm.

The inner walls of the aluminum cylinder liner are plated with chrome to increase wear resistance. The model is equipped with rubber shock absorbers that reduce the transmission of engine vibration to the handles. The Druzhba-4M model uses a KMP-100U carburetor, and with the Druzhba 4A modification, the use of forced chain lubrication began due to the installation of an oil pump. This made it possible to significantly increase the service life of the chain and guide bar.

How does the tool factory work?

The chainsaw is equipped with a carburetor two-stroke engine , which is practically its main element. Its power depends on the model of the equipment and its intended purpose.

The chainsaw saw set includes:

The larger the pitch the headset has, the more powerful and productive it will be, which means the deeper the cut will be . Therefore, the engine should not be inferior to it in terms of power, otherwise the operation of the tool will be inferior.

The chainsaw is lubricated with special oil directly from the second tank located on the hand block. Its mass has such features that the fuel and oil intended for the engine run out at the same time.

We have become familiar with the basic elements of the tool; now it will be easier to understand the reasons why a chainsaw may stop working and how to eliminate them.

What is good about Friendship-4 and its main disadvantages

The two-stroke MP-1 engine, rated at 4 hp, which gave it the number 4 in its name, developed for this chainsaw in 1953 at the Zaporozhye “Progress”, was, and remains, so easy to repair and maintain that it ensured its success for many decades.

But Druzhba-4 did not deserve its popularity with a single engine. The layout, convenient for long-term work, allows the feller to work standing, in a comfortable position, cutting trees almost close to the ground, and is not repeated in any other saw, except for those that are only its modifications. How many were there? Significant - really one, when the saw acquired a new, more powerful (5 hp) engine, gearbox with a saw chain lubrication system and the name “Ural”. It’s not worth talking about little things like the shape of the tank. And the reduction in weight, which is still hardly the biggest drawback of this design, from 12.5 to 11 kg, cannot be called a significant achievement.

The saw, which received a gold medal at the Brussels exhibition in 1958, was mass-produced until the end of the 90s with minor changes:

• in the 60s, changes were made to the handle fastening;
• in the 80s, the carburetor (“Druzhba-4A”) was replaced and electronic ignition (“Druzhba-4A-Electron” was installed);
• in the 90s, another new carburetor (“Druzhba-4M”) was installed.

The next stage was actually the creation of “Ural”, but it is only a development of “Friendship”.

Other modifications of this saw mentioned in some sources are the fruit of the authors’ imagination. The recently released Druzhba-2 saw has a traditional layout for this tool, similar to the models of market leaders Shtil and Husqvarna, and apart from the name, it does not in any way resemble its legendary predecessor.

Advantages of “Friendship-4”:

1. Ease of use when felling wood.
2. High maintainability.
3. Simplicity of design.
4. Low cost.

Also among the successful design features is the fastening of the gearbox using a clamp, which allows you to rotate it at any angle, which makes it possible to position the saw bar in a horizontal plane. A simple centrifugal clutch in which the outer L-shaped profile of the drive drum, as the speed increases, is pressed against the walls of the driven protrusion mounted on the gearbox, ensuring the transmission of torque.

Disadvantages of a chainsaw:

• Poor safety system (no automatic brake, stop button, vibration protection, etc.).
• Removable starter, which is often lost.

• Heavy weight.
• Low quality of spare parts.

The close relationship between “Ural” and “Druzhba” makes it possible to actively use spare parts from the first to the second. This is how saws made in the 60s gain a second youth after installing lubricated gearboxes with modern saw bars and chains.

And spare parts for Druzhba are still produced by many manufacturers and are not in short supply.

Moreover, based on its engine, not only saws were produced, but also motor pumps, winches, autonomous power stations and much more.

Characteristics

Over the 60 years of production, the design of the Druzhba chainsaw and its characteristics have changed insignificantly.

The general parameters are:

• weight when fully equipped - 12.5 kg;
• dimensions - 865x460x500 mm;
• saw bar length - 450 mm;
• The fuel tank capacity is designed for 1.5 liters of fuel liquid;
• spark plug - any with a diameter of 17 mm.

The main difference between the modifications is power. It is indicated by the number in horsepower at the end of the model names.

Friendship 2

The technical characteristics of this model are as follows:

• engine power - 2.2 kW;
• saw starting type - manual;
• lack of a rotary gearbox.

What makes Druzhba 2 different from the first model is the presence of a device for braking the chain, which made it safer: the tool cannot accidentally injure the worker or the people around him. The material from which the case is made is reliable and can withstand any temperature changes.

Friendship 4

This model received a gold medal at the World Technology Exhibition in Brussels in 1958.

The technical characteristics of the chainsaw are as follows:

• power - 2.94 kW;
• engine oil tank volume - 150 ml;
• total shaft rotation speed - 5000-5400 rpm;

A gas-powered saw can cut through a trunk with a diameter of up to 50 cm in 1 minute.

Friendship 4M electron

The Druzhba 4M electron chainsaw is distinguished by the fact that this model is equipped with an electronic non-contact ignition system, which significantly increases the reliability of the engine.

The technical characteristics of 4M are as follows:

• power - 3 kW;
• fuel consumption - 720 g/kW h;
• the distance between the spark plug electrodes is within 0.6-0.7 mm.

The inner walls of the aluminum cylinder liner are plated with chrome to increase wear resistance. The model is equipped with rubber shock absorbers that reduce the transmission of engine vibration to the handles. The Druzhba-4M model uses a KMP-100U carburetor, and with the Druzhba 4A modification, the use of forced chain lubrication began due to the installation of an oil pump. This made it possible to significantly increase the service life of the chain and guide bar.

Chainsaw models

The overall design of the saw has not changed significantly over time, only individual parts have been modified. The number at the end of the model name indicates its power, for example, Druzhba 2 - 2 hp. In the first chainsaw produced, the handles were attached to the fan cover; later they began to be attached to the clamp that connected the gearbox and the engine. Model 4A, produced until the 80s, already used a contact magneto and a KMP-100 carburetor. Automatic chain lubrication was also used for the first time. Later it was discontinued and instead they began to produce the 4A-Electron model with electronic ignition.

In the 90s, the previous carburetor was replaced with a new KMP-100U. The chain saw became known as Druzhba-4M and was equipped with updated chains. Based on the Druzhba chainsaw, the Ural saw with more powerful characteristics was developed. The latest model produced with a similar design is Druzhba 5E.

Additional marking with the letter E or the word “Electron” means that the chainsaw uses an electronic ignition system.

make a chainsaw quieter

I also wanted to throw in 10 kopecks, because... I worked in a car repair shop before, they made direct-flow mufflers with bass tips for street racers. For those interested:

The insert is similar to that of an ice fishing drill. We turned the auger 20 revolutions and stuck it into the muffler pipe. The sound did not become quieter, but only changed. Roared on one note, on the letter: Sh-Sh-Sh-Sh-Sh-Sh-Sh!!!!!! Like an air compressor hose with a sandblaster. Wild and unpleasant.

I would choose electric saws so that I can use them wherever possible, and start the petrol one when it is impossible to work electric... Electric saws probably don’t work, because... We’ve already bought a bunch of chainsaws, it’s also expensive to buy an electric one... The quietest but non-mobile option has already been mentioned - a hose in a bucket of water. This is how lumberjacks and poachers use chemicals. If the muffler is in the form of a barrel cube, then unscrew the 3 bolts (nuts) that stick out from it, take out the plug (or what’s inside? A cone?) and put a homemade flange of some kind on the 3 holes, to which a hose is connected to a bucket of water . The main thing here is to count: cut 10-12 of these flanges from roofing iron with metal scissors or make 10-12 noise-proof fences. By the way, stock up on hoses - rubber ones burn out quickly, you need something with metal. shell. And as for “the engine won’t work properly,” look at how the Americans have converted 2-stroke chainsaws on their model airplanes: just an exhaust pipe and that’s it!

How to check the ignition of Friendship

If the internal combustion engine of a chainsaw fails, in addition to the fuel supply, first of all check for the presence of a spark on the spark plug:

1. Remove the cap and unscrew the spark plug.
2. The spark plug thread is shorted to ground (cylinder ribs), and the starter is pulled. Contact ignition produces a large blue spark. Electronic - small yellow, difficult to see in sunlight. But this is the norm for electronic systems.
3. If there is no spark, replace the spark plug with a guaranteed good one and check again.
4. If the problem is not in the spark plug, remove the cap from the spark plug wire and, when the starter jerks, check for the presence of a spark between the bare wire and the ground with a gap between them of 0.2-1 mm.
5. If there is no spark at the output, check or change the spark plug wire.

Malfunctions of the Ural chainsaw and how to eliminate them

When repairing a Ural 2t chainsaw, it is possible to eliminate any faults, including replacing the crankshaft, piston system, etc. Let's skip major and medium-sized repairs, and consider minor ones, which any untrained user can do.

Oil pump repair

The oil pump of the Ural 2t Electron chainsaw most often stops working when the oil supply channels become clogged. They are simply cleaned. The engagement of the worm gear with the gear may also disappear. Sometimes the defect can be corrected by turning the screw that secures the gear. As a result, the position of the parts changes, they become closer to each other and the engagement is restored. If the teeth are completely worn out, the parts are replaced.

Chainsaw Ural does not gain momentum

This problem can occur due to many of the above reasons. But two particular points need to be highlighted.

• If the internal combustion engine idles steadily, but chokes when you press the gas, there are problems with the fuel supply. Fuel is supplied in sufficient quantity for operation at low speeds. However, it is not enough to develop full speed.
• The throttle (gas) cable is broken. The user presses the throttle, but the throttle valve in the carburetor remains in the idle position. The cable can break either at the ends, at the points of attachment to the handle and flap, or along the length, inside the shirt.

Won't start, but there is a spark

If there is a spark, problems in the operation of the ignition system can only be due to misadjustment. Spark in the Urals 2t The electron should flash when the piston has not reached T.M.T. 3.66 mm. If the fastening of the ignition unit is loose and it turns, the ignition is interrupted. It is checked by matching the two factory marks on the block and the body. If there is a spark and the ignition is adjusted correctly, then the reason is the above problems with the fuel supply.

Starter repair

The Ural chainsaw uses a removable starter. When the cable is pulled from the starter, the ratchet extends and engages with the engine ratchet. After the start, the return spring retracts the starter ratchet to its original position.

• The cable broke.
• The return spring is broken.
• The ratchet teeth are out of alignment.

READ Adjusting the carburetor of the Champion 138 chainsaw

The cable and spring are replaced. The life of the ratchet can be extended by unscrewing the ratchet from the engine flywheel and placing a washer under it. Then the engine ratchet will extend further and engagement will be restored. But you can't push the ratchet too far. From the ends of the engine ratchet teeth to the end of the crankcase cover flange there should be no more than 21.6 mm. Otherwise, after starting the chainsaw, the ratchets will not disengage.

Starts and stalls: what is the reason

There can be many reasons. But they always start looking from the simplest:

• The fuel tank is running low.
• The air filter is clogged with dust. A mixture that is too rich enters the combustion chamber and there is not enough oxygen to burn it out completely.
• The breather - a tiny hole in the gas tank cap - is clogged. A vacuum is created in the tank, and gasoline is not pumped into the carburetor. The breather is cleaned with a thin needle.
• The fuel filter at the bottom of the tank is clogged. It is pulled out with a wire hook along with the fuel hose attached to its fitting. But before doing this, you should remove the fuel supply hose from the carburetor. If gasoline flows out of it in a full stream, then the breather, hose and filter are clean.
• Carburetor misadjustment. The fuel supply adjustment screw (not idle speed) is unscrewed a quarter of a turn and changes in the operation of the internal combustion engine are checked. If it gets better, unscrew it another quarter turn. If it gets worse, they twist it back. In any case, you need to remember how much the screw was unscrewed or tightened. It is better to adjust with the engine running and warm.

Repair and adjustment of the carburetor from the Ural 2T Electron chainsaw are presented in the following

Further problems with fuel supply are more serious:

• the carburetor holes, filters, and channels are clogged;
• The carburetor membrane has become unusable.

Diagnosing these problems will require disassembling the carburetor.

Carburetor KMP 100

• Poor contact with the spark plug in the spark plug cap.
• When the internal combustion engine is running, the cap heats up and contact deteriorates. The temperature of the cap is tested by touch only with the engine turned off.
• With other problems with ignition, the internal combustion engine either does not start at all, or “fires” due to an adjustment failure.
• The cylinder exhaust ports or muffler are clogged with carbon deposits.

At low speeds there are few exhaust gases; they only need to exit through a narrowed passage. When the speed increases, the passage is small and the engine chokes. For a visual inspection, remove the muffler or the entire cylinder head. Contaminated parts are soaked in gasoline or special complex solutions and cleaned.

Carbon deposits in the exhaust system, on the spark plug, and coking of the piston rings are the weak points of old chainsaws. Their fuel mixture is filled with 2.5 - 3 times more motor oil (type M8) than in modern chainsaws: 15:1 during break-in and 20:1 during continuous operation. This large amount of oil does not burn out and forms carbon deposits.

No spark on the Ural chainsaw

The unit often fails due to overheating and when the engine suddenly stops at high speeds. Therefore, it is strictly forbidden to turn off the chainsaw with the “Stop” button or by removing the spark plug cap at high speeds.

They begin to look for the reason for the lack of spark from the simplest:

• Replace the spark plug with a guaranteed good one.
• Change the spark plug wire.

Spark plug wires for chainsaw Ural 2t Electron

If they are not the reason, replace the entire electronic ignition unit.

• Unscrew the candle.
• The thread or hex key is connected to ground by pressing it to the cylinder with a hand wearing a dielectric glove or with pliers with an insulated handle.
• Pull the starter and check for a spark.

It is important to know that electronic ignition produces a high-temperature, yellow spark that is barely visible in sunlight. The spark from the mechanical breaker is large, bright blue and cooler. Therefore, a small spark on electronics, almost invisible in the light, is normal. This should not be misleading to former owners of chainsaws with a mechanical breaker.

Non-contact ignition of a Ural 2t Electron chainsaw This is what a dismantled ignition without a flywheel looks like

Sources:

https://stroivagon.ru/instrumenty/zazhiganie-benzopilyi-ural.html https://schemy.ru/info/kak-proverit-katushku-zazhiganija-na-benzopile/ https://benzopilok.ru/remont/neispravnosti -benzopily-ural-2t-elektron.html

DIY repair

When the above measures do not eliminate the problem, the reasons may be as follows. The electronic ignition unit has failed. All elements of this unit are sealed (filled with compound) and cannot be repaired. The entire unit needs to be replaced.

The cam (contact) ignition system of the Druzhba chainsaw is repairable. There are several reasons for its failure:

1. The textolite insulator of the moving contact of the breaker was pierced to ground. Replaces with a working one without any options.
2. The moving and fixed contacts of the breaker (cams) were burnt. Clean with a fine file or emery until the surfaces are smoothly adjacent to each other. They change when completely burned out.
3. The capacitor is designed to protect contacts from burnout. It rarely fails and does not directly affect the formation of a spark. When diagnosing, it is simply ignored.
4. Interturn short circuit, break in the secondary high-voltage turns of a coil with a thin wire.

How to set the ignition on a Friendship chainsaw?

The list of signs that can indicate the need to adjust the ignition of the Druzhba saw includes:

• problems with starting a cold and hot engine - the engine does not turn on after numerous manipulations with the starter cable;
• random shutdown of the engine when pressing the accelerator;
• loss of traction - the engine slows down and stalls when the gas lever is depressed.

The design of the Druzhba chainsaw includes a 3-pin block, which is responsible for generating an impulse and supplying a spark to ignite the fuel mixture in the cylinder. The manufacturer has a mark on the reel in the form of a horizontal line.

The corresponding mark is on the standard crankcase body. To adjust the ignition of the chainsaw, you need to align both marks and tighten the fasteners.

Operating instructions for the “Druzhba” petrol saw

This document contains the following information:

1. Device, assembly diagram of the Druzhba chain saw.
2. Technical characteristics of a gas-powered saw.
3. Safety precautions when operating and servicing a chain saw.
4. Preparing for launch.
5. Run-in.
6. Maintenance of the Druzhba chain saw.
7. Malfunctions of the Druzhba chainsaw.

Let's briefly go through the sections:

Chainsaw safety

• do not operate the saw with the air filter removed;
• hold the instrument with both hands;
• use special clothing and protective equipment;
• do not adjust the carburetor if you lack the skills;
• use only high-quality mixture;
• do not work with an empty oil tank;
• do not operate the saw if it is faulty;
• ensure the absence of strangers in the workplace;
• take 10-minute breaks every 45 minutes of work;
• do not use pure gasoline, only when mixing gasoline and oil;
• When replacing the headset, turn off the saw motor.

Preparing to launch the Druzhba chainsaw

1. Chainsaw assembly.
2. Mounting the bar, tensioning the chain.
3. Preparing the fuel mixture.
4. Refilling the unit with technical fluids.
5. Launch according to the descriptions in the manual.
6. Functionality check:
   brake system;
7. idle move;
8. lubrication supply systems.

The fuel mixture is prepared from AI-72 or A-74 (now AI-92) unleaded gasoline and 2T AK-10 motor oil. The ratio of gasoline to oil for normal operation is 15/1. The correct way to dilute liquids is as follows: pour half the required amount of gasoline and all the engine oil into the container, mix the liquids well, add the rest of the gasoline and thoroughly mix the contents of the container again.

Running in the “Friendship” chainsaw

Run-in duration is 30 hours. The procedure is carried out in 2 stages:

1. Duration 5-10 hours (you need to burn 4 full tanks of fuel mixture at idle).
2. Duration 20-25 hours (about 8 full tanks of fuel are burned during operation with minimal loads).

Until the break-in procedure is completed, it is prohibited to remove the retaining ring installed between the carburetor cap and the throttle.

Maintenance of saw “Friendship”

1. Cleaning and lubrication of the saw body and main components and mechanisms.
2. Filter and spark plug maintenance.
3. Adjusting the carburetor, fuel pump;
4. Sharpening the chain.
5. Replacing the sprocket.

We invite you to watch a short video on how to adjust the carburetor on a Druzhba 4M Electron chainsaw:

Video

The following video will show how to sharpen the “Druzhba” chainsaw chain (straight tooth).

Video

Typical malfunctions of the Druzhba chainsaw, their causes and elimination

1. The engine will not start:
   there is no fuel in the fuel tank;
2. low quality of the mixture;
3. the filter is clogged;
4. no spark at the spark plug;
5. contact is lost;
6. the gap is not set;
7. break of a high-voltage wire;
8. damage to spark plug insulation;
9. fuel lines are clogged;
10. the carburetor is out of order;
11. piston wear;
12. ignition problems;
13. the fuel line valve is closed;
14. magneto failed;
15. problems with spark plugs.
16. The motor stalls, the power drops, the saw operates intermittently:
    problems with candles;
17. the carburetor has lost its settings;
18. the filter is clogged;
19. piston wear;
20. low quality fuel.
21. The chainsaw cuts poorly, with effort:
    the chain is dull;
22. chain lubrication is not supplied (the holes are clogged or the oil tank is empty);
23. improper sharpening;
24. the chain is overtightened.

The “Friendship” chainsaw starts and stalls - the reason (video):

Video

see also

Comments 77

Without knowing it, he “killed” his Patriot. Suddenly the saw stopped starting. I checked the spark, everything was fine, just in case I bought a spark plug in reserve. I checked the spark again and the saw does not start. Reloaded with the same effect. I took it to the service center two days later for an obituary of thermal scuffing in the combustion chamber. I figured it would be easier and cheaper to buy a new chainsaw.

Sprinkle some gasoline into the chamber and try to start it. If possible, then check the fuel and the fuel line.

It still didn't start.

I bought a new spark plug and it started. Now I'll set up the carb and that's it

Everything would be so easy to solve