Friendship chainsaw ignition coil 4 pin ignition

Repair of the ignition system of the Druzhba-4 chainsaw

The operation of the Druzhba-4 chainsaw revealed a number of shortcomings.
What is especially annoying is that it is almost impossible to start a hot engine. The cause of this “illness” is a weak ignition system.

To increase the power of the spark on the spark plug, the ignition system must be redone. Such a modification can also be useful in the absence of a working magneto coil for the standard ignition system.

For the modification, the low-voltage and high-voltage windings are removed from the standard magneto coil. Instead of low-voltage winding with PEV-2 wire with a diameter of 0.8 mm (this type of wire is used for winding transformers, chokes, etc.), 250 turns are wound. Interlayer insulation is required: after each layer of wire, a gasket is made of paper or varnished cloth. The beginning of the winding is soldered in place of the standard terminal to the core, and from the end of the winding a terminal is made with a mounting wire for connection to the ignition breaker. The coil is insulated on top (you can use insulating tape).

The circuit of the capacitor connected in parallel with the breaker and the coil remains unchanged.

Next, conclusions are drawn using two mounting wires through a piece of rubber hose as a seal. To ensure reliable insulation of the wires, it is advisable to combine them into a common sheath of PVC tube.

A B-115 ignition coil with a remote resistor, which is attached to the side of the coil, is used as a step-up transformer. This type of coil is found in the ignition systems of Moskvich, Volga and other cars. The use of motorcycle ignition coils is undesirable: they do not provide sufficient spark power. The ignition coil is attached using a clamp to the chainsaw frame in any convenient place.

The wires coming from the engine “snail” are connected as follows: one, coming from the common connection point of the capacitor, breaker, coil output - to the “VK” terminal of the B-115 ignition coil; the second, coming from the ground and connected to the magneto mounting bolt - to the terminal of the B-115 ignition coil, which does not have a designation. It is advisable to choose wires of different colors.

Next, the ignition coil is connected with a high-voltage wire to the engine spark plug.

Adjusting the ignition timing gave very good results, all the “illnesses” of the chainsaw disappeared. For several years now, the redesigned ignition system has been working properly on the Druzhba-4 chainsaw.

In conclusion, we can say the following: the ignition coil slightly “spoils” the appearance of the saw, but it is better to have a saw that is reliable in operation than one that brings nothing but torment.

This ignition system can also be used on other types of engines, which was tested on moped engines of type D-5, D-6. The winding in this case contains 160 turns.

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

The design and principle of operation of the ignition system on a Druzhba chainsaw

For more than 30 years, until the end of the 1980s, Druzhba chainsaws were produced with contact ignition (mechanical breaker). The principle of generating electricity is the same as that of more modern electronic systems. A magnetic rotor mounted on the crankshaft rotates inside the coils. The primary winding of the coil consists of several turns of thick copper wire and produces a current of low voltage (V, Volt), but quite high strength (A, Ampere).

The secondary winding consists of many turns of thin wire. In some ways it is a step-up transformer. Passing through it, the electric charge changes its characteristics. And the output voltage is 15-30,000 V at a scanty current (milliamps). This current is capable of producing a high-temperature spark (arc) between the electrodes across the gap, which can be observed on each spark plug.

The latest modification of this chainsaw with contact ignition, Druzhba 4A, was produced until the end of the 1980s. Afterwards it was replaced with Druzhba 4A Electron with contactless ignition, as indicated by the prefix in the model name.

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 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.

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.

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.

The main thing is not to damage the insulating layers of varnish during dismantling.

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.

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