Replacing the high-voltage wire on a chainsaw

How to check the ignition of Friendship

If the internal combustion engine of the chainsaw fails, in addition to supplying fuel, first of all, the presence of a spark on the spark plug is checked:

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

Starting the engine: checking the candles

If the 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 simply will not start.

After making sure 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 the 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 with the high-voltage wire or in it.

Other chainsaw malfunctions

If the diagnostics showed that everything is in order with the engine and its systems, then the cause of the malfunction should be looked for in other units of the chainsaw. The most common problems are:

• failure of the starter;
• improper operation of the lubrication system;
• incorrect operation of the chain brake;
• saw chain wear, etc.

If the cause of the failure of the tool is not visible to the naked eye, as is the case with the engine, it is necessary to perform a thorough diagnosis of the faults and eliminate them in accordance with the manufacturer’s recommendations and safety regulations.

Chainsaw design and general classification of faults

Correct diagnosis is essential for a successful repair. Therefore, in order to determine why the chainsaw failed and, most importantly, how to make it work again, you first need to know the features of its design.

It should be noted that it does not differ in particular complexity, since it includes:

• engine (two-stroke gasoline);
• functional part (saw bar and chain);
• systems that ensure the joint operation of these two units (ignition, filtration, lubrication, etc.), that is, the tool as a whole.

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.

The most common malfunctions 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.

Signs of a faulty ignition:

• The chainsaw starts, but works unevenly (troit), sneezes and shoots often;
• The power of the chainsaw has dropped noticeably;
• With a sharp press on the throttle trigger, dips in the engine are observed;
• The chainsaw does not start well on a cold one, strongly troit until it warms up;
• Fuel consumption has increased significantly;

If such flaws appear in the operation of your chainsaw, then it’s time to diagnose, adjust, and possibly repair the ignition system.

Chainsaw ignition step by step:

• We diagnose a malfunction;
• We dismantle the protective cover;
• We remove the module with a candlestick and an electric cable. We carry out their visual inspection, if necessary, we replace them with a new one;
• Install the ignition module, but do not tighten the fastening screws all the way;

• Determine the area with the magnet on the flywheel;

• We set the gap properly, in accordance with the parameters specified in the instruction manual;
• We tighten the screws that secure the module to the stop, check the settings with a probe, and, if necessary, re-adjust;
• Install the protective cover and check for a spark on the candle;
• We screw in the candle, start the chainsaw;

Important: when repairing the ignition of a chainsaw, special attention should be paid to setting the correct gap between the module and the flywheel.

You should also check if the flywheel is clinging to the module with the counterweight. If this happens, you may have a bearing failure or a backlash on the shaft.

Chainsaw ignition Druzhba

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

over, sometimes it is possible to alter a failed old contact ignition coil, and install it instead of a failed electronic version.

Replacing high-voltage wires Chevrolet Aveo 1.6

One of the important systems in a car is ignition. Among others parts for Chevrolet Aveo, included in this block, special attention should be paid to high-voltage wires.

The main purpose of high-voltage wires is to transmit a high-voltage electrical impulse from ignition coils directly on candles. In this case, the charge should not significantly decrease, otherwise there will be problems with the ignition of the air-fuel mixture.

An important factor when choosing high voltage wires is the resistance indicator. The optimal value can be called a value up to 10 kOhm. In this case, the wires conduct the impulse without problems without losing much of its charge.

Too low resistance value can cause the ignition system to interfere with other electrical equipment of the Chevrolet Aveo.

It is worth noting that the wires must meet the requirements for safe use, be resistant to external aggressive influences, including high temperatures. Particular attention must be paid to the resistance of the conductor to break.

The design of a high-voltage wire largely depends on the number of insulating layers. Single-layer wires are distinguished, in which there is only a conductive core and insulation, two-layer, in which there is a core, a dielectric and protective layer.

The most reliable in terms of work are three-layer wires. They consist of a core, dielectric and protective layers, as well as a reinforcing braid. However, the cost of such wires is quite high.

Also on each high-voltage wire there is a cap and a tip that acts as a contact.

The following factors may indicate the presence of problems with high-voltage wires of the Chevrolet Aveo:

• Having problems starting engine.
• Unstable operation of the power unit at idle.
• Changing exhaust parameters.
• Formation of radio interference, which can affect the operation of the car audio system, electronic control unit.

It is worthwhile to periodically check high-voltage wires, especially if the above symptoms appear, and the examination of other blocks did not give any result. It is enough to use a tester to check the resistance of the wires, which in the optimal case should be in the range from 1 to 10 kOhm.

If certain problems have arisen with the wires, then it is better to carry out a complete replacement, since they are practically not subject to repair and restoration.

We deal with the high-voltage wires of the Chevrolet Aveo after installing the 2nd generation LPG

The problem is that after the installation of the 2nd generation HBO, strange pops began to form. Ultimately it can lead to rupture collector, which is plastic on this car. Accordingly, it will have to be replaced and a new one installed, which is quite expensive.

To replace high-voltage wires, you must perform the following steps:

• Unscrew the plasticcoveron car engine.

• This requires a 5 mm hexagon.
• We sketch the layout of the wires on the coil, which will allow us to set everything correctly in the future.

• Sami cylinders go in a row, from left to right from 1 to 4.
• We remove the high-voltage wires of the Chevrolet Aveo.

• If, when removing the wires, traces of oil are found on the cap, then it should be checked and replacedgasketcovervalves, which, most likely, began to leak.
• We disconnect the wires, which are fastened together with the help of specialretainers.

• Using a tester, we check the removed wires.

• We connect contacts to different sides of the wire.
• 3 out of 4 wires turned out to be quite working, with normal resistance values.

• However, when tested, one of the wires showed a different resistance, which sometimes reached over 50 kOhm, which indicates its failure.

• The cause of the malfunction was the penetration of the graphite core, which ultimately led to complete damage to the wire. If such a wire is not replaced in time, then there may be problems with the ignition coil.
• We moisten a screwdriver in water and insert it under an elastic band.

• This must be done carefully so as not to damage the rubber band of the high-voltage wire cap of the Chevrolet Aveo.
• It is necessary to insert the screwdriver in several places, in a circle, so that the elastic comes off well and does not stick.
• Using round-nose pliers, fix the pin and gradually tighten the elastic.

• We insert scissors or other object of a suitable size into the locking antenna.

• Then we inflict a slight blow to the base of the contact.

• This will allow you to easily remove the plastic part from the high-voltage wire.

• Use a screwdriver to unclench the retainer and remove the iron tip from the wire.

• The main thing is not to bend the round base, which is worn directly on the spark plug.

• We tear off the cap from the wire.

In the meantime, there is no need to worry about it. ”

• Using pliers, remove the sleeve from its.

• The remnants of the wire can be squeezed out of the cap by substituting a metal rod with a diameter of about 8 mm and a length of about 20 cm.

• We insert a new wire into the tip of the high-voltage wiring of the Chevrolet Aveo.

• We clean the edges of the new wire from insulation.

• A metal contact is put on the wire.

• Then it is fixed with pliers.

• Lowering the rubber tip.

• On the other hand, a sleeve is put on.

• Clamped with pliers.

• If a protrusion is formed from the insulation, then it can be cut off and it is better to fix the rest of the elements.

• If the plastic part does not completely fit into place, then it can be hammered into a hard surface.

• We put in place the rubber tip.

• We install high-voltage wires in place.

• We check the performance.

Thus, you can replace the high-voltage wires on the Chevrolet Aveo. Instead of the old ones, new wires were installed, without resistance, which will maximize their efficiency.

In this case, some problems may arise in the operation of the audio system, as well as sensors, but in most cases everything will function normally.

Self repair

To carry out repairs at home, you need spare parts, tools and appropriate skills. For example, for disassembling a chainsaw, a homemade repair kit can be useful, which will have to be made for a very long time.

Some modern semi-professional and household devices do not include the appropriate tools for adjusting the carburetor and disassembling the drive sprocket.

Engine malfunctions

• The engine will not start;
• starts, but stalls;
• works unstable;
• does not develop power, i.e. works normally at idle, but stalls under load.

When repairing a chainsaw with your own hands, you need to act by the method of exclusion. to check in turn all possible causes of a malfunction, starting with those whose check and elimination takes less time (about the device and operation of a two-stroke engine, see here).

Ignition system. Almost all of the engine problems listed above can be caused by a malfunctioning ignition system. Therefore, when they occur, it makes sense to start troubleshooting with a candle. This is all the more justified since the state of the latter can provide useful information about the operation of the fuel system. So, if a problem occurs, you need to unscrew the candle and inspect it.

The wire is disconnected and the candle is unscrewed with a special key.

If the spark plug is dry, this means that the problem is most likely not in the ignition system, but in the fuel mixture entering the cylinder. You can wrap the spark plug back and start the fuel system. If the spark plug is heavily splashed with a fuel mixture, then there is an excess of it. This can occur from a misalignment of the carburetor or a violation of the starting rules. The spark plug is wiped and dried, the cylinder is drained by shutting off the fuel supply and operating with the starter to ventilate the combustion chamber and remove excess fuel. Then put the candle in place and repeat the start.

The presence of a large amount of black carbon also indicates a malfunction in the fuel system.

The ratio between oil and gasoline in the mixture may be disturbed, the carburetor is not adjusted or poor-quality oil is used. The candle is washed in gasoline, cleaned with a needle or an awl from carbon deposits, the electrodes are cleaned with a fine sandpaper and installed in place.

In all these cases, it will not be superfluous to check the gap between the spark plug electrodes. Depending on its brand, it should be in the range of 0.5-0.65 mm. It is also necessary to check the spark plug gasket. If it is worn out or damaged, the tightness of the combustion chamber may not be ensured, which leads to a decrease in compression in the cylinder and problems in engine operation.

Even if, when checking the spark plug, there is good reason to believe that the problem is in the fuel system, you need to check the spark plug for the presence of a spark. If only to be sure that everything is in order with it. For this:

• put the ignition cable on the spark plug;
• using pliers with insulated handles, apply the thread or nut of the candle to the cylinder;
• pull the starter handle and see if there is a spark or not.

If there is no spark, you just need to replace the spark plug. If the new spark plug does not have a spark either, you need to check the condition of the high-voltage wire for an open circuit and contact with the spark plug.

The reason for the absence of a spark may also lie in a faulty ignition module or a violation of the gap between it and the flywheel magnetic circuit. It should be 0.2 mm. A gap violation becomes especially likely if the saw was disassembled before the flywheel and ignition module were removed. The gap is set with a 0.2 mm spacer placed between the flywheel boss and the ignition module. Defective ignition module must be replaced.

Having checked the ignition system in this way and not finding a malfunction, you can go to the fuel mixture supply system.

Fuel supply system. If by inspection of the spark plug it was found that fuel does not enter the cylinder, all possible reasons for this need to be considered. This could be:

• no fuel flow from the tank due to a clogged hole in its lid (breather), while a vacuum is created in the tank, which prevents fuel from flowing out;
• contamination of the fuel filter installed in the tank;
• non-flow or insufficient flow of the fuel mixture from the carburetor to the cylinder.

To diagnose the first two reasons, it is enough to disconnect the fuel hose from the carburetor and see if fuel is leaking from it or not. If it flows with a full stream, the breather and filter need not be checked, if it does not flow or flows weakly, we can assume that the cause of the malfunction has been found. The breather is cleaned with a needle. The fuel filter is removed through the filler opening of an empty fuel tank, with a wire hook, together with a suction hose from which the filter is disconnected and cleaned or replaced with a new one. Chainsaw manufacturers recommend changing the fuel filter every 3 months.

Insufficient flow of the fuel mixture from the carburetor into the cylinder or a violation of the correct ratio between fuel and air mixed in the carburetor can occur for several reasons: due to clogging of the air filter, unregulated carburetor, clogging of its channels or filter mesh.

As a rule, the repair of chainsaws is not complete without cleaning the air filter, since it gets dirty quite quickly. When this happens, the intake of air into the carburetor is reduced, the fuel mixture at the exit from it is too rich, which disrupts the normal operation of the engine. Remove the dirty filter for cleaning carefully so that dirt from it does not get into the carburetor. The filter should be cleaned or washed in water with some kind of detergent, dried and reinstalled.

The misalignment of the carburetor is eliminated by adjusting it. This is usually done with three screws. the maximum and minimum speed and the idle screw. The adjustment must be carried out in strict accordance with the instructions, non-observance of which may lead to engine damage. Some saw manufacturers keep only one adjusting screw (idle) to prevent unwanted interference by inexperienced users with the carburetor. For an example of adjusting the carburetor of a chainsaw, see the article Working with a chainsaw.

If adjusting the carburetor did not help, you need to clean its channels and filter mesh, and at the same time check the integrity of the membrane. The carburetor is one of the most complex chainsaw devices, so you need to start disassembling and cleaning it with a full understanding of the responsibility of this operation. It consists of many small parts, which have the peculiarity of jumping out of their places imperceptibly and being irretrievably lost, so, having disassembled this capricious device, you may not need to assemble it.

Below is a diagram of another chainsaw carburetor.

Muffler. Often, the cause of engine malfunction, especially in the case when the engine normally operates at low speeds and stalls under load, is clogging of the muffler’s spark arrester with combustion products, which prevents normal exhaust. Repair in this case consists in removing the muffler, disassembling (if it is collapsible) and wet cleaning it from carbon deposits using detergents. The non-dismountable muffler is dried with a hairdryer after washing. Remember that carbon deposits contain substances that are carcinogenic and should not be dry cleaned, which could result in inhalation. When removing the muffler, plug the engine outlet with a clean cloth.

One of the reasons why the muffler can clog is the use of a fuel mixture with an excessive amount of oil (the amount of oil is more than the manufacturer recommends), and the use of either oil that is not intended for two-stroke engines or low-quality oil.

Cylinder-piston group. Malfunctions of the cylinder-piston group are among the most serious. This is the worn out cylinder and piston, scratches and scuffs on their surfaces, wear or sinking in the grooves of the piston rings, wear on the crankshaft bearings. Most of these malfunctions lead to a drop in cylinder pressure and, as a result, to the inability to start the engine, or its inability to deliver full power. There are several ways to assess the state of the cylinder-piston group (CPG).

You can remove the muffler and look through the opened window, in which part of the side surface of the cylinder is visible. Despite the limited review, a general idea of ​​the state of the CPG in this way can still be obtained.

It is useful to measure the compression in the engine, which is informative enough regarding the condition of the parts of the CPG. The operation is carried out using a compressometer installed in the candle hole.

The crankshaft is turned using an electric motor (drill) with a flexible shaft or manually with a starter, while controlling the pressure on a pressure gauge. The latter for a working chainsaw should be at least 8-9 atm (0.8-0.9 MPa). With its decrease, the engine power also decreases. At a pressure of 5 atm, the engine may work, but only at idle.

It is possible to accurately assess the state of the CPG only by completely disassembling the engine. by disconnecting the crankcase from the cylinder and removing the piston. If the latter has seizures, chips or deep scratches, it must be replaced. With regard to the cylinder, if the surface is worn out or damaged, it is possible to bore it to the repair size. The reason for low compression may be wear or coking of the piston ring. A serviceable ring should be clean from carbon deposits, sit freely in the piston groove and press tightly against the inner surface of the cylinder.

Cylinder-piston group

It happens that the engine does not start or malfunctions due to low cylinder pressure. The malfunction may consist in a worn out piston, cylinder or bearings, sinking of the piston rings. You can consider the problem in general terms, for this you need to remove the muffler and inspect the system.

Compression in the engine can be measured by placing a compression gauge in the spark plug hole. After a while, you can draw conclusions based on the results of the measurement. You can only consider the problem by completely disassembling the system. If scratches or chips are visible on the piston, then it needs to be replaced. The piston ring must be installed in its rightful place, clean and intact.

Chainsaw design

All chainsaws have the same design, regardless of which device, domestic (Ural, Kedr, Patriot 3816, Carver. Russian production with Chinese partners) or foreign (Stihl, Husqvarna), for example, repairing a Patriot 3816 chainsaw with your own hands will be the same as well as fixing a foreign device. The main components of the tool:

• Engine.
• Fuel tank.
• Starter.
• Handle.
• Tire with chain.

The general principle of the chainsaw is simple. the master sharply pulls the cord, which starts the engine, and he, in turn. the saw blade. Sometimes, the device malfunctions, in order to eliminate them, you will have to dismantle the saw. Problems that may arise with a chainsaw:

• It just won’t start.
• Starts up, but after a while stops working.
• Doesn’t work in the cut.
• Power drops.

The main problems that arise are related to engine problems (fuel supply, exhaust system, cylinder-piston system and ignition), or smaller problems (chain problems, lubrication, tire, oil seal). It is important to consider each problem in more detail.

If the chain simply breaks, then it should be replaced with a new one. There shouldn’t be any problems with solving this problem. Repairing other parts of the saw can take up to several hours.

No matter how trite it may sound, if the chainsaw does not start, then you need to check the tank for the presence of gasoline. If there is fuel in the system, then the breather may be clogged, equalizing the pressure when fuel is supplied. The breather can be cleaned with a sharp awl or needle. With a candle wrench, the candles are turned out and cleaned with sandpaper. You can also ventilate the combustion chamber. After these procedures, the saw should start.

If the saw shuts off automatically, the trigger is most likely defective. But sometimes it happens that it’s not about him. In this case, you need to unscrew the candles and inspect them carefully. If traces of fuel are visible on them, it means that the carburetor is incorrectly adjusted. The spark plug must be cleaned and placed back, after shutting off the fuel supply.

If black carbon is visible on the candles, then the matter may be in poor-quality oil, a poorly adjusted carburetor and an incorrectly calculated ratio of oil and gasoline. In this case, you also need to clean the candle and place it back.

When checking the spark plug, you need to consider the distance between the electrodes. The optimum clearance is between 0.5 and 0.65 mm. The used gasket must be replaced with a new one.

It is also important to check the device for sparks. This is easy to check: you need to connect the spark plug to the ignition cable, use pliers to connect the cylinder and the plug nut, and then observe the presence of a spark. If not, the candle must be replaced. If, when changing a candle, it turned out that the other does not give out sparks, then the problem may be an inoperative contact with a candle or a high-voltage wire.

General disassembly principles

Basically, all chainsaws have the same components, which are dismantled according to a certain scheme. If the assembly of the saw is Chinese, then there is nothing to worry about: most often they are made in the likeness of European models. How to disassemble a chainsaw:

• The clutch cover is removed.
• The starter cover is removed. To do this, you need to unscrew the screws and remove the cross handle.
• To remove the handle, you need to remove the cover that covers the air filter.
• The petrol hose is removed from the fitting cover.
• The saw body is dismantled. It is necessary to unscrew the screws and remove the oil tank cover.
• Before removing the ignition module, you need to disassemble the clutch drum: you need to turn the crankshaft clockwise until the piston closes the gas outlet.
• Then you need to unscrew the clutch on the chainsaw and remove the clutch: you need to lightly hit it with a hammer.
• The screws are removed, the gas tank with the oil hose is dismantled.

Possible problems

The main problem that arises during the repair is the lack of the necessary information on how to carry out the repair. This is due to the fact that many foreign manufacturers believe that the saw should be disposed of after a certain period of time and use up. Therefore, many craftsmen have certain doubts, especially when repairing budget models.

But expensive professional models also create certain difficulties:

• The first problem is to supply expensive spare parts.
• For the maintenance and repair of some units, special equipment is useful.

How to avoid scoring on the piston of a chainsaw

Greetings, dear readers! Spring is coming, and many will go to the country. And this means that the time has come to share your experience as a repairman for garden motor vehicles. This article is just part of a small series. Here are links to other articles:

During the work of the workshop, I have accumulated an impressive collection of photographs of various malfunctions in which a collection of photographs of failed cylinder-piston groups occupies a special position.

Melting of the top of the piston. The photos show cracks and a hole in the piston crown, as well as splashes of molten aluminum in its interior. This happened due to the fact that the owner of this trimmer put the wound tool aside and began to chat with a neighbor in the country. After chatting for about five minutes, he gave the gas to full ( you cannot work at half a gas ) and began to work, but the trimmer instantly stalled and stopped starting because the piston bottom began to overheat during idle time and simply melted.

Two-stroke engines of garden equipment are cooled due to two things: forced blowing of the cylinder by the flywheel impeller and the air-fuel mixture entering the crankcase. The first cools the cylinder more, the second the piston. Never leave your chainsaw idling for more than a minute, rather turn off the engine.

Piston and cylinder seizure. They can occur for a number of reasons, the first of which is dry contact. As a rule, a large number of small seizures on the piston indicates that pure gasoline was used during operation, and not a fuel mixture. Let me remind you that the working revolutions of the chainsaw are in the region of 11-12 thousand per minute, with such a speed the chainsaw will not work “dry” even for a minute. A similar picture will be observed when using old fuel. As a rule, seizures appear on the side of the exhaust window, in the area most critical of oil starvation.

Specifically for this piston, it is quite difficult to say from what it suffered more. Judging by the soot on its upper part, the oil was poured anyhow, without observing any proportions. The muffler of this unit was also clogged with soot, and clear fuel was drained from the tank. Apparently, it was pure gasoline, or a very old mixture. But the old mixture most often becomes cloudy, so two conclusions can be drawn: either the mixture is old, but the oil in it is not two-stroke (some of them pour motor oil, unwittingly), or it is pure gasoline.

Engagement and breakage of piston rings. And here is an example of what happens if, when preparing the fuel mixture, the proportion is violated and the oil is poured much more than the required amount. As a result of using a mixture with a high m of oil, or a mixture with oil not intended for two-stroke engines, intense ash formation was caused, followed by the occurrence of piston rings, one of which broke off and caused critical damage to the piston. It should be noted that rings breaks not so often, I would even say that it is quite rare, but this does not make the engine easier.

In the technical regulations for old Soviet motor vehicles, I often came across two “recipes” for preparing a fuel mixture for one and the same machine. One proportion was considered more environmentally friendly (the one with less oil), the other extended the engine life (the one with more oil). But that was before, with old technology and old oils. Nowadays there is a continuous struggle to reduce the harmfulness of exhaust, the oils have a completely different composition and the engine is of a different design, so I recommend that you use the proportion that the manufacturer himself indicated on the canister of the oil that you have chosen.

And here is an example of a piston with a coked ring and a small seizure. Fortunately, this unit was restored without replacing the CPG, escaping only by cleaning the piston from carbon deposits, a little grinding and replacing the piston ring. The entire piston surface is covered with tar and ash deposits, here the use of a low-quality fuel mixture is beyond doubt. The cylinder was slightly damaged, small workings and lack of honing are visible, but no scoring is observed.

Output. Use only high quality. always a fresh fuel mixture prepared using two-stroke oil. Do not overheat the tool or leave it idling for extended periods. Perform timely maintenance, clean and inspect your tool after work.

Chain lubrication system

In case of significant (small is considered normal) oil leakage, it is necessary to check the tightness of the connection of the pipes to the pump unions. They can subside or crack. Violation of the tightness of the oil line, in addition to drips, can lead to insufficient lubrication of the chain. The pump begins to suck in air, which affects its performance. The violation of the tightness is eliminated by replacing the tubes or sealing them with a sealant.

The most serious failure of the lubrication system is cracks in the oil pump housing. In this case, it will have to be replaced.