Detailed review of the Friendship chainsaw

Man and saw. History of Friendship

The saw design was tested back in 1953. Only two enterprises produced the saw, the Perm and Biysk plants, but due to the fact that the demand for the model has always been high, its production has recently been mastered at numerous small-scale enterprises. Mass production of Friendship began in 1955, and three years later the saw was shown at an international exhibition in Brussels, where it received a gold medal.

There are a lot of speculations about the name of the device, including the Druzhba cheese, an allegedly joint Soviet-Chinese development, and even the 300th anniversary of the signing by Bogdan Khmelnitsky on the inclusion of the left bank of Ukraine into Russia. No one really knows how it was, but it is a fact that the chainsaw became an ideal replacement for the two-handed saw, which was also called Friendship.

The chainsaw index always includes a numerical value - this is the engine power in horsepower. Sometimes the letter E appears, indicating the use of electronic non-contact ignition. The design of the saw was excellent. Separately the engine, and separately the sawing mechanism. They simply twist into a single block and, if necessary, in a few minutes you can gain access to any mechanism and part, and without tricky pullers and special experience and skills. The only difficulty with a completely politically backward element was the adjustment of the primitive carburetor, which, despite the prehistoric design, honestly did its job.

Druzhba chainsaw engine

The Druzhba chainsaw, whose technical characteristics were ensured by an almost perpetual motion machine, thanks to the engine, received great respect from its zealous owners, but not only them. Entire hordes of home-made workers, entire generations of technical maniacs were inspired by this simple motor, which was available for free sale. A lumberjack from British Columbia would never understand what this engine meant to mechanical engineers. There were practically no engines of this volume and such power in the country, and microcars and homemade agricultural equipment were assembled on the basis of the device, even the production of small X3 aircraft was prepared. Propeller-motor units consisting of 4 saw engines were mounted on them.

True, they never went into production because they did not officially pass flight tests. But the industry of the country of the Soviets pounced on the engine and frantically began to introduce into production a lot of equipment that needed a small-capacity, reliable gasoline engine:

walk-behind tractors;

• autonomous water pumps;
• generators for field tractor camps and taiga work crews;
• lawnmowers;
• mechanical winches;
• engines for water transport.

This is how 4 horsepower in a ridiculous volume of 94 cm³ came in handy for the needs of the national economy of a huge country.

Druzhba M 3150-1 Chainsaw

• Description
• Characteristics
• Reviews
• Delivery
• Payment
• Pickup
• Service and repair

Peculiarities:

• Chainsaw Druzhba M 3150 is a tool for collecting firewood, trimming branches, clearing forests or gardens; the saw will also help when working on a construction site.
• Improved starting system Ergo Start - inertial engine starter.
• The anti-vibration system, automatic chain lubrication and brake, with emphasis on protection, make working with the saw safe and convenient.
• Carburetor licensed by Walbro (Japan).
• Quick-release (for cleaning) volumetric mesh air filter
• Drive sprocket of the Powermate system.

Specifications:

Equipment:

• Tire 450 mm. - 1 PC.
• Chain 0.325″, 1.3 mm, 72 stars - 1 pc.
• Universal key - 1 pc.
• File - 1 pc.
• Container for preparing gasoline-oil mixture - 1 pc.
• Instructions - 1 pc.
• Warranty card - 1 pc.

Modifications and design of the Druzhba chainsaw

Over the 60 years of production, the design of the Friendship has remained virtually unchanged. This is still the same two-stroke stokubovy engine, from time to time engineers increased the power, depending on the application of the engine, but on chainsaws it remained unchanged. A little later, electronic non-contact ignition began to be installed on motors, which significantly increased the reliability of the motor.

Until the end of the 80s, the Druzhba 4A with an electric magneto and a KMP 100 carburetor was produced; after the use of a non-contact system, the saw became known as the 4E Electron; in the 90s, the designers modernized the carburetor and the saw received the prefix M, and later, based on the design elements of the Druzhba, they developed more productive saw Ural.

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.

The problem is also that Druzhba-4 chainsaws of late production may have different carburetors, completely different in design from the KMP-100. For example, with one adjustment screw or no adjustment options at all.

Chains for chainsaws Friendship, repair and price

Friendship, like any mechanism, can break down. And unexpectedly and for a long time. But those who know its vagaries are always ready to repair the device, even in the middle of a field or in the taiga. The main problems with the saw were related to contact ignition and the carburetor. The fact is that, contrary to talk about the omnivorous nature of the saw, not every gasoline could make the engine work at full capacity. That is, it worked, but constant ignition adjustment was required. The engine was too sensitive to the octane number of the two-stroke mixture of gasoline and oil that it was powered by. Contacts, as a rule, cannot be repaired, and if they are restored, it will not last long. It’s better to immediately replace them with new ones, and even better to immediately install a contactless system.

Another problem with the motor part of the saw was the leakage of the power system. Today, in principle, it is already possible to use sealants, so this issue is losing relevance. As a rule, the mating surface of the carburetor and cylinder must be sealed especially carefully. The chains and saw mechanism require only periodic lubrication and rarely fail.

The device, which has unprecedented reliability and endurance, a gold medal from the exhibition and the ardent love of the public, is still in production and you can buy Friendship in Metal for 6-7 thousand, depending on the modification, and forget about the problems with sawing wood for a long time.

Characteristics

Friendship-2

This model became one of the most popular of the entire original series. The Druzhba-2 chainsaw is powered by a two-stroke single-cylinder engine with a power of about 2.2 kW and a rotation speed of 3200 rpm. Compared to the previous version, this one was performed with better quality. The frame and handle are made in such a way that the user cannot get burned on the hot engine. The case is made of high-quality alloy, which is not afraid of temperature changes. Unlike the first model, this one already has a mechanical chain brake for safe use. In the event of a rebound or breakage, it will stop the chain. The saw was intended both for domestic needs and for professional felling of forests. Weight 12.5 kg.

Friendship-4

The Friendship 4 chainsaw uses the same engine as the previous model, but with more power – 4 hp. or 2.94 kW. The engine and power unit are installed using a flange connection secured with a clamp. If necessary (repair, replacement), the engine can be easily removed in any conditions. Based on the Druzhba 4 saw, two modifications were produced, marked 4A and 4E. The first one added an automatic saw chain lubrication system, and the second one used electronic ignition. The shortcomings of previous models were also taken into account, for example, the crankshaft bearing was strengthened. All versions were produced with an emergency braking system.

The Friendship 4M-Electron chainsaw uses a similar engine with a power of 2.94 kW and a rotation speed of 5200 rpm. The cylinder is made of aluminum alloy, and the inside is treated with chrome to increase wear resistance. Unlike earlier versions, this chainsaw is equipped with a rotary gearbox, which allows you to rotate the saw unit by 60-90° for more convenient operation. The weight is distributed evenly throughout the body to make work as comfortable as possible. There is also a vibration damping device located between the steering wheel with handles, struts and the gas tank.

To reduce the noise level, the saw is equipped with a muffler, and the noise level is 106 dB. The Druzhba 4M-Electron chainsaw is equipped with a KMP-100U or KMP-100-AR carburetor. There are automatic braking and saw chain lubrication systems. Weight 12.5 kg.

Friendship-5E

The latest version of this series of chainsaws released. Equipped with a two-stroke single-cylinder engine with a power of 5 hp. or 3.7 kW. Due to this, its performance is noticeably higher than that of previous models. Rotation speed 6200 rpm. At the same time, the noise level emitted is slightly lower than that of Druzhba-4M Electron, and is 105 dB. The weight of the 5E chainsaw is 800 grams less - 11.7 kg.

Table with technical characteristics of Druzhba chainsaws: