What Should Be The Spark On A Chainsaw
Chainsaw ignition Chainsaw ignition system. This is a whole complex of elements with the help of which a spark appears when starting the engine. It is needed in order to ignite the fuel
Most often, breakdown occurs due to the spark plug. It is worth checking if the insulator is damaged and the electrode is not worn out. Check the entire candle for integrity and the absence of defects, this is the integrity of the wires from the coil, and the presence of insulating material, etc.
Chainsaw ignition module (coil) problems
The switch and the ignition module that regulates its operation can often fail. The coil may also be faulty. If all elements of the ignition system are in good working order, but there is no spark, suspect the module and the coil. And the problem of a malfunction of these elements is that it is impossible to repair the module or to fix part of the coil, they need to be replaced. Of course, if possible, it is better to put the module from some old saw and see if this is the case. After all, you can simply make a mistake at some stage and suspect what actually works.
Do not trust all kinds of testers, they often show false information about the health of the ignition system. Only diagnostics with a different module or coil will be valid.
If the electronic module is bad, there is such a symptom: as soon as the chainsaw heats up, a very weak spark is emitted. Also, after refueling, the unit may not start. This is due to the fact that the coil or module is very hot, their resistance increases, so the spark weakens.
If there are breakdowns in the ignition system, and there is no experience in repairing them, you should not try to repair everything yourself. Elementary things, such as checking the integrity of a candle or wires, can be carried out at home, but more complex diagnostics, and even more so, the replacement of units should be carried out by professionals. And then you can be sure of the quality of the work performed.
The main malfunctions of the ignition system of chainsaws
Roughly understanding how the ignition system of Chinese or domestic-made chainsaws works, you can already figure out what problems there may be with this mechanism and how to fix them.
On / off button
A frequent breakdown of the ignition system is a malfunction of the shutdown switch. To check it, the wires are disconnected from the module and the operation of the saw is checked. If there is a spark, it’s the switch.
Chainsaw ignition scheme Ural
High voltage wire
Next, check the spark plug wires. They can often run in such a way that many bends are observed. In those places, the wire can be damaged, while it looks perfect. Next, inspect the spark plug cap of the ignition wire. There should be no brown coating on it. If there is one, this means that the spark is not firing in the right place, but in all parts around the ceramic insulator. The cap can also be damaged, cracks, chips. The check must be carried out carefully, because due to the damaged insulating layer, you can get an electric shock.
In all other cases, the search for ignition problems begins from the end and in order. A spark is checked after each step.
- They change the old candle for a guaranteed working one.
- If the model has a removable candle cap, it is removed, the bare candle wire is shorted to ground with a gap, approximately like a candle. Pull on the starter. If there is a spark, the problem is in the cap. It is being eliminated.
- Change the spark plug wire where it is possible to dismantle it from the source.
- Visually inspect the wires from the switch. Vibration, in case of contact with metal, can damage them. If there are places of friction, the wire is changed, even if there is no external damage to the insulation. You can use a tester or multimeter to test the wire.
This is where minor and easily fixable problems end. If the problem is not resolved, then the cause is more serious. Modern coils and ignition systems on most chainsaws are very reliable. They are designed to last even longer than the entire chainsaw. They do not have mechanical moving parts like the old cam systems. They are sufficiently insulated from clogging and moisture.
If, due to an accidental factory defect, an interturn short circuit occurs in the coil or the electronics fail, these parts cannot be repaired. Replacement with new ones will be required.
There is not a rare breakdown of mechanical properties. Due to wear or destruction of the crankshaft bearing, play appears on it. And then the magnetic rotor begins to touch the housing of the ignition system, inside which it rotates. This is a serious breakdown. You will need to halve (disassemble) the entire motor, replace the bearing, and put everything in place.
Why there is no spark on a chainsaw and what to do
If there is no spark on the chainsaw, then do not get upset, the malfunction is diagnosed and fixed on its own very simply. The correctness of the ignition system and the fuel system are equally important for the trouble-free operation of the chainsaw engine. But the symptoms of both ignition and carburetor malfunctions are often very similar at first glance. To correctly find and eliminate the cause of malfunctions in the ignition system, in particular the absence of a spark, you need to know the principle of its operation, device and diagnostics.
Weak spark reasons
A weak spark on a chainsaw is a relative concept. Most often, there is a spark, and the ignition is correct, or there is none at all. In modern chainsaws with electronic ignition, the spark visually seems to be weak.
On older models with a mechanical cam interrupter, the spark was large, with a strong blue color. On modern models with electronics, it is noticeably smaller and paler, more often yellowish. Therefore, when you need to make sure of its presence, it is better to do it in the shade. In direct sunlight, it is almost invisible.
How to make sure there is really no spark
To make sure there is a spark on the chainsaw or not, you need to follow a simple procedure:
- The top cover on the case is removed.
- Carefully, with a grip at the very bottom, so as not to tear off the candle wire, the cap is removed from the candle.
- Using the 19 socket wrench included in the kit, the candle is unscrewed counterclockwise.
- The cap is put on in place, on the candle.
- The thread or nut of the candle is shorted to ground, that is, pressed against the metal cylinder head. To ensure reliable contact, the candle is pressed against the cylinder with electric pliers, a screwdriver with insulated handles, or with a hand with dielectric gloves. You should not do this with your bare hand. If the cap breaks down, you can get a painful shock from a high-voltage discharge (up to 40,000 V at a low current strength of up to 80 milliamperes).
The chainsaw is placed on the ground, pressed with your foot to the ground and lightly pulled on the starter cord. At this time, it will be seen whether there is a spark or not.
It is important that there may be no spark on the chainsaw due to a malfunction of the fuel system. In order not to look for a problem in a working ignition, this issue must be dealt with immediately.
The carburetor of a chainsaw can overflow, that is, throw too much fuel into the combustion chamber. Inside the candle there is a porcelain insulator from which a metal core emerges. On it, under the plate, they contact the mass (minus) and a spark arises.
But if the space inside the plug between the round insulator and the mass is filled with excess fuel, especially together with conductive pollution, a short (spark) can slip inside the plug. There will be no spark where it is needed.
However, if there is no spark on the chainsaw, the fuel does not burn, and the spark plug must simply be wet with fuel when the carburetor is running. It is practically impossible to determine visually whether the candle is overly flooded and therefore there is no spark, or not excessively. Therefore, for an accurate diagnosis of this nodal moment (a carburetor or ignition is faulty), you need to have at hand 2-3 guaranteed serviceable candles.
- A working candle is placed.
- The spark is checked.
If there is a spark, it means either:
- The old candle was defective;
- The old plug is working, but it was filled with fuel.
The working candle is screwed into place, the engine is tried to start. If it started working normally, the problem is resolved. If not, turn the candle inside out again and watch the spark. No spark put the next dry working candle.
There is a spark, they put the candle in place, try to start it. If it does not start again, turn the candle inside out, watch the spark. If the spark on the chainsaw disappears again, and the candle is flooded, there is almost a 100% chance that the cause is fuel overflow.
Reasons for the absence of a spark
The engine of each chainsaw is, in fact, a miniature power plant. She receives the primary impulse for the spark on the candle from the pull of the starter cord, from muscle energy.
Further, energy is generated due to the rotation of the magnetic rotor when the engine is running due to the combustion of fuel. In theory, spark problems can be found throughout the entire mowing line of a system, from generating power to transmitting it through wires and converting it to a spark plug at the chainsaw spark plug. In practice, there are fewer weak points.
Checking the ignition system
The first thing to do if the chainsaw breaks down is to inspect the spark plug by disconnecting the wire and carefully unscrewing it with a special key.
Chainsaw ignition system components: 1 flywheel with magnets, 2 ignition module, 3 spark plug, 4 high voltage wire
Unscrew the spark plug to check its condition.
Her appearance says a lot:
- Dry. Most likely, the fuel mixture does not enter the cylinder. It’s not about the ignition system, so the plug is screwed back in.
- Strongly splashed with fuel. The reason for the excess fuel mixture lies either in the violation of the starting rules, or in the incorrect adjustment of the carburetor. The spark plug is carefully wiped, shut off the fuel supply and turn on the starter to remove excess fuel and ventilate the combustion chamber. Then the candle is put in place and the mechanism is started again.
- Covered with black carbon. This may indicate the use of low-quality oil, an incorrectly adjusted carburetor, or an incorrectly calculated gasoline to oil ratio. The candle should be washed, cleaned of carbon deposits with a sharp object (awl or needle), wipe the electrodes with a sandpaper and put in place.
When checking the candle, you need to pay attention to the gap between the electrodes: it is considered normal from 0.5 to 0.65 mm. A damaged or worn gasket must be replaced.
A large amount of black carbon on the spark plug indicates a malfunction of the engine.
To be sure, you should also check for a spark. To do this, put the ignition cable on the spark plug, connect the plug nut and the cylinder with pliers, start the starter and watch for the spark. If it is missing, the plug must be replaced. If the new spark plug also does not produce a spark, the problem is in the high-voltage wire or in a broken connection with the spark plug.
Repairing the chain lubrication system
Consider three main faults:
- Oil leakage. Check that the pipes are tightly connected to the pump unions and if they are cracked. Problem tubes are sealed or replaced.
- Insufficient oil supply. Most likely the lubrication passages are clogged.
- Cracks in the oil pump housing. Part replacement required.
Here’s how to diagnose the lubrication system:
Constructive components of the chainsaw
All chainsaws are similar in structure, regardless of whether they are European (ECHO, Stihl, Husqvarna) or domestic (Kedr, Ural). Inside the body are the main elements of the fuel tank and engine, and outside the starter, handle, saw part (tire) with a chain. A sharp jerk of the cable starts the engine, and that saw blade.
To begin with, we suggest that you familiarize yourself with the rollers, which show how the chainsaw works and how it works:
From time to time, the saw malfunctions, which require disassembly to eliminate. What can happen to such a simple mechanism as a chainsaw? At least the following:
- Ceases to start;
- Starts up, but soon stops;
- Ceases to function in the cut;
- Loses its power;
Most of the malfunctions are associated either with interruptions in the operation of the engine (fuel supply system, exhaust system, ignition, cylinder-piston part), or with malfunctions of other systems and components (clutch, chain brake, tire, lubrication system). Consider the most common breakdowns and techniques for their elimination.
A working chainsaw starts with one jerk and does not fail in the cut
Dismantling and cleaning the muffler
If the engine works fine at low speeds, and at high speeds it starts to stall, the reason may lie in the muffler spark arrester, clogged with combustion products.
- Remove the muffler;
- Disassemble (there are also non-separable models);
- Clean from carbon deposits using detergents;
- Dry with a hairdryer;
Dry cleaning is unacceptable, as the soot contains carcinogens, the inhalation of which is dangerous to health. After removing the muffler, close the outlet with a clean cloth.
Interruptions in the operation of the chainsaw signal a possible clogging of the muffler
To prevent the muffler from clogging, it is necessary to monitor the composition of the fuel mixture. The amount of oil should not exceed the rates recommended by the manufacturer. Poor oil quality also negatively affects engine performance.
Assessment of the state of the cylinder-piston group
Often the engine will not start or run at full strength due to low cylinder pressure. It can be caused by piston or cylinder wear, piston ring sinking, bearing wear. You can partially examine the condition of the cylinder-piston group (CPG) by removing the muffler and looking into the opened hole.
A compressor placed in the spark plug hole will help to measure the compression in the engine, according to the measurement results, you can also talk about the state of the CPG. Accurate data is obtained only after the complete disassembly of the mechanism. If the piston is chipped or scratched, it must be replaced. The piston ring must be clean, free of carbon deposits, and be exactly in place.
Piston and crank mechanism wear is considered a serious problem.
According to the results of measuring the compression, one can judge the condition of the parts of the CPG
Do-it-yourself chainsaw repair: analysis of major breakdowns and methods of their elimination
It would seem, why does a chainsaw need a summer resident who grows vegetables and fruits, or a country house owner who has a small garden and several flower beds? The question disappears when there is a desire to build a bathhouse, update a greenhouse, knock down an old business, or just make a bench for relaxation. Unfortunately, any mechanism periodically needs preventive maintenance and replacement of spare parts, and for this you need to be well versed in the device of the product, besides, repairing the chainsaw with your own hands will save time and money.
To check the chain tension, the saw brake must be disengaged. Then manually pull the chain along the bus, if it runs smoothly and does not sag, then everything is fine. If the chain is very tight, then it needs to be slightly loosened, because there is a risk of rupture during operation.
Poor drive sprocket
One of the possible options for a dangling chain on your device leading sprocket problem. Most often, everything happens due to the fact that the star is poorly fixed. Now we will tell you how to properly fix the star and then put the chain on the chainsaw.
First you need to remove the engine protection cover. Next, remove the protective cover of the spark plug, pull out the air filter. Then you need to unscrew the candle with a special key. A special stopper is placed in its place, which fixes the piston in a certain position. With a special key (you can use a universal wrench for a grinder), turn the clutch disc clockwise until the piston reaches the uppermost position. Looking into the hole of the plug, the piston should remain at the bottom. A thick rope can be used as a stopper; it is better to fold it several times. Once locked, the drive sprocket can be clamped by rotating the clutch disc counterclockwise.
After clamping, you need to do everything in the reverse order, that is, assemble the chainsaw. A chain is put on the tire; it must hit the drive sprocket that holds it. The tire is placed in special mounting holes and bolted. Then the defense is placed.
Installing the chain on a chainsaw, how to properly tension and check the tension
If you have a chainsaw at home, then you should know that it requires special care. It is necessary to periodically clean and sharpen the chains, clean the air filter, oil supply and tires. And, of course, you need to monitor the chain tension, since with a poor tension there is a risk not only to harm the saw, but also to your health if the chain falls off at high speeds.
- Chainsaw device features
- Why the chain flies, find out the reasons
- Bus problems
- The chain stretched
- Poor drive sprocket
The chain stretched
If your chain sags on a chainsaw, then this indicates a malfunction of some mechanism, one of the options is the wear of the chain itself.
Over time, the metal deforms and the chains become 0.5-1 cm longer. It is best to fix this problem by purchasing a new circuit, but there is a way to get the old one back. Experts say that this is very difficult and almost impossible, but we will tell you how you can do it at home.
For this we will need:
- Electric welding machine (not needed in all cases);
- A hammer;
A regular chainsaw chain is made of strong steel, so it is difficult to disconnect. You need to disconnect the chain on the inside of the rivet, which serves as a connecting mechanism.
First, the chains need to be fixed in a vice, and then gradually grind off the protruding part. You need to grind with a file or a file. It is not recommended to use a grinder, as there is a risk of damaging the lateral parts of the links. After sewing, the rivets are knocked out with a beard. The knocked-out rivet should not be thrown away. You may not be able to find a replacement. Manufacturers of gasoline saws do not produce individual parts for the chain, as they do not expect consumers to be able to repair the chain themselves. Most likely, you will not be able to make a new rivet yourself, so you will have to install the old one.
In order to shorten the chain, you need to split it in two places. But remember, that the number of guide lugs on the inside of the chain and the distance between them must match the drive sprocket.
After removing one or more of the links (depending on the degree of chain stretch), the chains can be connected. We connect to old rivets, while pressing them tightly on the sides.
Next, we need a welding machine. The rivet must be welded to the lateral parts of the link. After that, we grind off the excess that formed during welding with a file. The chain can be considered healthy again.
Chainsaw device features
The main part of the gasoline saw is engine. In most modern devices, the engine is single-cylinder. Air cooling, two-stroke piston system. Oil in these types of engines is added directly to gasoline, and all due to the fact that the fuel constantly flushes the crankcase. The oil-to-gasoline ratio varies from 1:20 to 1:50 depending on the manufacturer of the chainsaw.
The air filter on gasoline saws plays an equally important role. He needs regular cleaning. If the filter is heavily contaminated, dust from it will fall directly into the piston system, leading to engine damage.
If the filter is clogged, the saw will lose speed and the engine will overheat, which can cause the piston rings to burn.
The starter on gasoline saws is a rope with a handle that you pull on to activate the motor. When you pull on the rope, the teeth catch on the ratchet, and the flywheel begins to spin.
Many people complain about the long pulling of the rope to ignite the engine. It depends on whether the carburetor is correctly aligned. If the carburetor produces the correct oil-gasoline mixture, then there should be no problems.
Main working mechanism tire with grip.
The chain consists of three types of teeth: leading, cutting and connecting. They are riveted together. The cutting teeth are located on two sides: right and left.
Chains are divided into two types: high profile and low profile. The first type includes chains, in which the teeth are located with a large gap, to the second with a smaller gap. Chains can also vary in shank thickness and link length. The chainsaw chain is attached to a bar that guides it in the correct direction. The end of the tire has a specific groove that holds the links and allows the chain to rotate. A driven sprocket is located at the front of the tire. The chain together with the bar is called a headset, since they are detachable parts of the chainsaw.
The gasoline saw has an automatic chain lubrication system. The tire supplies oil, which is then absorbed by the sawdust. If the saw is idling, the oil supply stops.
Why the chain flies, find out the reasons
If you wondered why the chain on your chainsaw flies, then there is some kind of malfunction in the mechanism. Exist three main reasons This malfunction: malfunctioning bar, chain stretching and loose sprocket. Let’s take a closer look at each of the possible causes of breakdown.