How to check the ignition coil on a STIHL 180

Gasoline ignition. Layout, diagrams, malfunctions.

The chainsaw ignition system is the whole complex of components. the ignition system that creates the spark when the engine starts. It is needed to ignite the fuel and bring the engine into a state of full-fledged continuous operation. The main element of the ignition system is the spark plug, which must be ignited whenever the engine is in the right cycle of operation. And although the system is reliable and well-thought-out, but sometimes its repair is required, so the user needs to know how his chainsaw is arranged, as well as what he can do to repair its ignition system.

The ignition system of a modern chain saw

Earlier ignition systems were quite unreliable, but now they have improved. For example, their control system has elements that regulate the pulse depending on what saw speed. This makes the motor run more efficiently, which increases the overall efficiency of the tool. In addition, such elements are important because it is easier to start the saw initially with them.

Equally important is the reliability of modern systems. Whereas the ignition used to fail very often, now all of its components are so robust and of such high quality that they rarely need to be repaired.

So, the modern chainsaw ignition system is the flywheel magneto, the spark plug, the wire and the ignition switch. A distinction is made between contact and contactless magnetos. The structure of the first is quite simple: permanent magnets (installed in the flywheel rim), ignition coil, capacitor and breaker. The coil, in turn, includes the core, as well as the transformer primary and secondary windings. Another important element is the spark plug. Its construction is as follows: central and side electrodes, insulator, outer casing.

The interrupter and the primary winding of the coil are connected in series. The shear disconnect is created by the cam on the crankshaft. The primary winding is not only connected in series with the shearbolt, but also with the release button. The magneto is mounted in the crankcase on the left side, secured by the base on two studs and nuts.

The flywheel magnets generate a magnetic field which crosses the coil. Due to this, if the contacts in the primary winding are closed, a weak current is formed. Accordingly, when the contacts are open, there is no magnetic field and an EMF is induced in the secondary winding. This generates a high voltage current, which is fed to the spark plug and gives the spark to ignite the fuel. At this point the piston is nearly at its top dead center (4 mm below it).

Ignition device for chainsaws Ural-Electron 2 T and Druzhba

The engines of chainsaws Ural-Electron 2T or Druzhba, as well as Taiga-214-Electron have a slightly different ignition system. So, they use a contactless breaker

contactless electronic magnetos. In other words, they have no mechanical contact chopper.

What it means? The induced current is generated via the high voltage transformer. Its primary winding is connected in series with the thyristor through the charging winding, the capacitor diode and the control winding. Due to this complex system, a thyristor carries current only when a certain potential is applied to it.

As soon as the thyristor is open, the capacitor is discharged to ground. While a high pulse current is flowing in the primary winding, the secondary winding generates a high inductive voltage, which induces a spark on the spark plug. Through the thyristor and the control winding, a contactless breaker operates, which is highly reliable because it has no wearing parts.

The scheme of ignition of a chainsaw Ural

Druzhba chainsaw ignition diagram

Stihl Ignition Coil Bench Test and Replacement

The main faults of the chainsaw ignition system

Roughly understanding how the ignition system of chainsaws of Chinese or domestic production works, you can already understand what the problems with this mechanism may be and how to eliminate them.

Spark plug

Most often the failure occurs because of the spark plug. It is worth checking to see if the insulator is damaged or if the electrode is worn. Check the entire spark plug for integrity and absence of defects, this and the integrity of the wires from the coil, and the presence of insulating material, etc. д.

The high-voltage wire

Next, check the spark plug wires. Often they can run in such a way that many bends are observed. In those places, the wire can be damaged, while looking perfect in appearance. Next, inspect the spark plug cap of the spark plug wire. It should not have a brown residue on it. If there is one, it means that the spark is not shooting out in the right place, but all over the parts near the ceramic insulator. The cover may also be damaged by cracks, chips. It must be checked carefully because a damaged insulating layer can cause an electric shock.

On/off button

A common problem with the ignition system is a faulty on/off switch. To check it, disconnect the wires from the module and check the functionality of the saw. If the spark is there, it’s the switch.

Problems with chain saw ignition modules (coils)

The switch and the ignition module that regulates its operation can often fail. The coil may also be defective. If all elements of the ignition system are functional and no spark, the module and the coil are suspected. And the problem with malfunctioning these elements is that you can’t repair the module or fix part of the coil they need to be replaced. Of course if you can, it would be better to take the module from an old chain saw and see if that’s the problem. After all, it is possible to make an elementary mistake at some stage and suspect what is actually working.

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Do not trust all kinds of testers they often show false information about the health of the ignition system. Only a reliable diagnosis is possible with a different module or coil.

If the electronic module is bad, you can see this symptom: as soon as the chainsaw warms up, it produces a very weak spark. Also after refueling the machine may not start. This is because the coil or module gets very hot, their resistance increases, so the spark gets weaker.

If there are failures of the ignition system, and no experience in their repair, do not try to repair everything yourself. Elementary things, such as checking the integrity of the plug or wires, can be done at home, but more complex diagnostics, and even more so changing units should be performed by professionals. And then you can be sure of the quality of the work done.

Adjusting the carburetor on a STIHL 180 chain saw.

To adjust the carburetor STIHL 180 chain saw has only one screw. the idle speed adjustment screw. 1. Standard idle speed adjustment (abbreviated x.х.): turn screw counterclockwise until it is too tight, then make two revolutions clockwise and that’s it. 2. If the revolutions are too low x.х., then you have to turn the screw clockwise until the chain starts to move, and then turn the screw 0.5 turn counterclockwise. 3. If the rpm is too high x.х., turn the screw counterclockwise until the chain stops turning and then turn it another 0.5 turns anti-clockwise.

Adjusting the carburetor on the STIHL 180 chain saw is finished.

How to turn the ignition switch on the STIHL 180

All engines used on cars and other power tools with a combustion engine have the same mechanism.

Well known chainsaws are no exception and are used with great pleasure by users such as Goodluck, STIHL or Husqvarna.

They are driven by the familiar internal combustion engine, respectively the fuel tank, the engine and the working body specifically work, as well as other hanging bodies that help to manage.

From time to time in the process of use, there may appear some commotion, in this rather reliable tool as a chainsaw.


The main thing in this group of problems is the engine.

The ignition is one of the key elements affecting the tool’s trouble-free operation. So the first thing to consider is this block.

Gone are the days when ignition control was handled by a breaker with cams and a moving contact that provided the spark to the spark plug.

It was not a very reliable system because of the many elements that affect the operation of the engine. A chainsaw with no apparent malfunction could simply stop starting. And we could see the pattern of constantly yanking on the ignition cord. Nowadays, manufacturers have switched to non-contact ignition systems.

Purpose and principle of operation

The ignition coil makes it possible to convert a low-voltage electrical impulse from the current source into a high-voltage impulse, without which a spark cannot be produced. It can have from 1 to 3 lobes in the electrical breakdown gate. Depending on the powertrain specifications, the breakdown gap may be between 0.4 and 1.1 mm.

To ensure reliable ignition, the electrical impulse voltage must be at least 10 kV. One should remember about a possible voltage drop in the conductors and therefore the coil should produce a pulse of 12-20 kV.

This voltage can pose a serious danger to people and is especially true for those who suffer from various heart ailments. When checking a faulty coil, you need to be very careful because even standard rubber gloves can not guarantee complete safety. The way this element works is similar to an autotransformer. The primary winding is made of copper wire coated with insulating varnish. Most often the number of turns is 100-200. The secondary winding consists of a thinner conductor, but has 2000-3000 turns.

When the power plant is running, the cam mechanism located in the tumbler rotates. The main task of this element is to open the contacts. When a short circuit occurs, the primary winding carries a high current. This induces an induction in the secondary winding and the high voltage impulse is transferred to the spark plug gap.

This ignition circuit has been used in cars for a long time. Its main disadvantage can be considered the burning of the contacts because of the high current flowing through them. Often the owners of vehicles supplemented the factory scheme with a simple electronic amplifier.

Today the situation has changed and manufacturers actively use more reliable devices, e.g. Hall sensor, instead of choppers. If the user needs to know how to check the ignition coil of a chainsaw with a multimeter, this procedure is carried out similarly to that for testing car candles.

Yakov Sinelnikov, 56, Khabarovsk

“I bought an old chainsaw. Well, as the old. was at my grandfather for three years in the garage. I tried to start it, but it didn’t work. Looked at the plug, it did not seem to be flooded, it was dry. Unscrewed it, checked it. no spark. Had to take it apart and adjust the gap. Instead of the dipstick cut out a homemade dipstick from a plastic bottle, put it in and adjusted it. The chainsaw works fine. the main thing is to set the clearance and correctly assemble. The candle, by the way, also changed.”

Yaroslav Stembitsky, 37, Zhytomyr region

“The chainsaw wouldn’t start after the winter. Pulled the starter for a long time. my arm is tired, but it won’t start. Then I figured out to unscrew the spark plug and check for sparks. nothing, nothing. I took off the protective cap, looked. the gap is normal. Reassembled everything and it wouldn’t start again. Took me a day until I figured out to check the contact on the spark plug. Turns out the spring popped out. I can’t think why or when.”

Semyon Starodubtsev, 54 years old, Krasnodar

“Was clearing a garden in the spring, the chainsaw started to sneeze, and then it just stalled. Checked the spark plug. it was wet and I could see it was leaking. Cleaned the carburetor, changed the spark plug, but it won’t start. Checked it out, no spark. Took the ignition apart and found the cause. high voltage cable was all melted. I still don’t understand why it happened. Changed the cable with the module. now everything works fine.”

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Checked the ignition coil on my chainsaw

If the preparatory acts did not help in identifying the prerequisite defects in the chainsaw, then you need to check the ignition coil of the saw. Diagnosis is made in several steps:

  • Measure the coil resistance using a multimeter. It is necessary to know the rational characteristics, which are stated in the instruction manual. But because of the use of semiconductor parts in the system, if you try to “wire” the coil, the result will be a “Circuit Breaker” reading. This is normal. A sign of malfunction is a good check result. Т. е. If you can find the resistance of the coil with a special tool, then it is definitely faulty.
  • Check the presence of the spark with a special device. This device should be installed in the circuit break between the spark plug and the high-voltage lead of the saw’s ignition coil. The characteristics will be seen on the screen. This way of checking is often used in service centers, because the device is expensive and the cost is not commensurate with its usefulness.
  • Testing the coil with a candle, t. е.Perform a homemade ignition. For this purpose, it is necessary to unscrew it and then put the housing to the cylinder. Now pull the starter and watch for sparks. But this method gives only a rough result, as the flywheel spins faster because of the unnatural position of the candle.

READ Disassembling a Partner 350 Chainsaw Video

If none of these methods did not give results or as the need to perform the test in the field criteria, you can proceed as follows:

  • Take the cap off the spark plug, drive a nail without a cap in the core at 6-7 mm from the cylinder. This should be done very carefully so as not to destroy the part.
  • Perform the acts that are required to make the winding tool. Now you need to look at the spark and its color. If there is no fault, the spark is strong and the color is bright blue.

This method can be used in the latter case, and only if there are no electrical nodes, with all the fundamental to make the rules:

  • You can not quite unscrew the spark plug, as this can lead to a sharper rotation of the flywheel, which is not the correct mode of operation of the motor;
  • have to have at a distance that matches the model compression and dielectric properties of fuel consistency, because this parameter can be seen in the manual (the value of 6-7 mm is average).

Replacement of the ignition coil in the trimmer. DIY!

Bypassing ignition coil replacement

, Shows a method to simply make a slot at home criteria.

The insidiousness of such a failure is that the diagnosis of the following methods does not give a 100 percent confidence in the performance of the ignition coil. Such an implicit failure when the spark seems to be there, but it is not quite right, often misleading and forced to write off difficulties with the ignition coil on a faulty carburetor. The usual action in such cases is to increase the fuel supply. It turns out that such a spark can ignite an enriched mixture, but the correct one cannot. But the introduction of enriched consistency leads to a sharp wear and tear of the cylinder-piston group and muffler. module, ignition coil of brushcutter (lawnmower) How to set the ignition on the trimmer ECHO srm 22 ges. That’s why in such disputable situations check both the carburetor and the ignition coil once again.

STIHL 180 chain saw ignition adjustment

In this review presented to your attention will try to solve the question that many chainsaw owners. When using such a tool the user may encounter a situation where the ignition timing needs to be corrected. Over time, the breaker can fail, the coil is also not eternal, although it serves much longer and it is quite difficult to break it. So let’s figure out how to set the ignition on the chainsaw.

Constructive components

All engines whether it is automotive or other tools that use internal combustion engine have similar working principles.

Not an exception there are such famous chain saws and they are gladly used by consumers as Goodluck, STIHL or Husqvarna.

They are driven by the familiar internal combustion engine, respectively, fuel tank, the engine and the working body that performs the work itself, as well as other attachments that help to drive.

Sometimes in the process of operation some problems may occur, in this rather reliable tool as a chainsaw.

So what do you do??

Here are some common cases:


The main problem in this group is the engine.

The ignition is one of the main elements affecting the trouble-free operation of the tool. So first let’s take a look at this unit.

Gone are the days when ignition control was done by a chopper with cams and a moving contact that provided the spark to the spark plug.

It was not a very reliable system because of the many elements that affected engine performance. No apparent problems with the chainsaw might have prevented it from starting. And we may have seen a pattern of constant yanking on the ignition cord. Today, manufacturers have switched to non-contact ignition systems.

They have fewer moving parts and do not have contacts that need to be periodically aligned, often failing. The coil used on a modern chainsaw will last the life of your tool. The chainsaw has become much more reliable and easier to service.

Possible malfunctions

If the saw doesn’t start the first thing to check is the spark plug, which gives the spark and ignites the fuel in the cylinder. Start by removing the high voltage lead where the spark plug is connected. Then unscrew the spark plug itself from the cylinder head and inspect its condition. The candle should be dry when working properly and small deposits on the ceramic are light in color:

  • If the spark plug is wet then there is a problem with the carburetor. You need to adjust and set the fuel level in it;
  • Dark or black soot on the walls of the spark plugs means that the piston group is defective.
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If here you can not find any visible cause of the fault, the spark plug is dry, the soot is light continue to go from the opposite direction. As this is the final point of ignition of the mixture. Now check to see if the spark is coming from the spark plug. This is the ignition unit.

To check whether there is a spark is not a problem, just take a high-voltage cable to which the plug is connected, bring it to the cylinder block, exposing them to a small gap, so you can see the slip of a spark between them. Then pull the starter cord and see if there is a spark and what color it is. A working spark plug should give a lightning-like spark. As it looks, look at the photo offered to your attention, it shows everything well.

If you don’t see any spark, check with a test light, or if you don’t have a tester, check the high-voltage cable. There may be a breakage at the point where it was kinked most often. If the wire is okay, it’s possible that the problem is the wrong ignition angle. It could be too early or too late in either case the chainsaw starts well and will not work.

Now let’s try to set the correct gap between the mobile and fixed contact. Ideally, it should be 0.2 mm. You can check it with a feeler gauge, fortunately it is not in short supply.

That was a description of the faults of the older chainsaws. New generation chainsaws include modern Goodluck, STIHL and Husqvarna.

Modern Systems

Modern systems have chips that regulate all of the above problems. Way to independently set the ignition advance angle depending on the engine speed and power transmitted to the cutter. The engine helps to save fuel without compromising performance. Also much easier to start the saw, no matter what the weather conditions.

The chainsaw itself has become easier and more efficient and does not require expensive repairs. Ignition coils made by modern technology and using new materials have literally become eternal.

In addition to everything you have read here is a video for a full review of this material.

How to ignite the STIHL chain saw 180?

Chainsaw repair with your own hands

All chainsaw malfunctions can be divided into two main groups: problems with the engine with all its components and systems (ignition, fuel supply system, cylinder-piston group, exhaust system) and problems with other components (chain brake, lubrication system, clutch, tire, etc.).).

Engine trouble

  • The engine won’t start;
  • starts, but stops;
  • works unsteadily;
  • does not develop power, t.е. works normally at idle speed, but stalls under load.

Carrying out repair of a chainsaw with their own hands, it is necessary to act the way of exception. to inspect all the possible causes of failure, starting with those, check and fix which takes the least time (about the device and work of the two-stroke engine, see here).

Almost all of the types of engine problems listed above can be caused by ignition system failures.

Therefore, when they occur, it makes sense to begin troubleshooting with the spark plug. It is all the more justified, because the condition of the latter can give useful information about the operation of the fuel system.

So, if a problem occurs, it is necessary to unscrew the plug and check it.

The wire is disconnected and the spark plug is unscrewed with a special wrench.

If the spark plug is dry, it means that the problem is most likely not in the ignition system, but in not getting the fuel mixture into the cylinder. It is possible to screw the plug back in and start working on the fuel system. If the spark plug is heavily spattered with fuel mixture, it means that there is an excess of fuel.

This may be caused by the carburettor being out of tune or by breaking the rules of starting. Wipe and dry the spark plug, dry the cylinder, cut off the fuel supply and work with the starter in order to ventilate the combustion chamber and remove the excessive fuel.

Reinsert the spark plug and restart.

check, ignition, coil, stihl

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

The oil to petrol ratio in the mixture may be faulty, the carburettor is out of adjustment or low-quality oil is used. The spark plug is washed in petrol, cleaned from sludge with a needle or awl, the electrodes are finely sanded and refitted.

check, ignition, coil, stihl

In all these cases it is worth checking the gap between the 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 or damaged, the tightness of the combustion chamber can not be ensured, which leads to reduced compression in the cylinder and engine performance problems.

Even if in the case of checking the spark plug, there is great reason to believe that the problem is in the fuel system, you need to check the plug for a spark. If only to be sure that there is nothing wrong with it. To do this:

  • Put the spark plug cable on the spark plug;
  • Using pliers with insulated handles, put the thread or nut of the spark plug to the cylinder;
  • pull the starter handle and see if there’s a spark or not.