The 5 most important chainsaw malfunctions: causes and solutions
Technology is becoming more and more perfect and intelligent year by year, more complex in design and easier to use. Chainsaw manufacturers can not keep up with the times: special anti-vibration systems, easy starting, automatic chain lubrication, chain tensioning without a tool… But no matter what additional features would be equipped with a model, it is not immune to failure. With chainsaws in any price range, the vast majority of breakdowns can be avoided with proper care and use of the equipment.
IF YOUR SAW HAS A PROBLEM THAT IS NOT DESCRIBED IN THIS ARTICLE, CONTACT CUSTOMER SERVICE FOR ADVICE!
In this article, we will cover the main causes of chainsaw malfunctions and how to diagnose and fix them.
This article covers the following points:
Chainsaw engine malfunction
Signs of chainsaw engine malfunction:
– the engine does not start – the engine runs unstable – the engine starts, but frequently stalls – the engine overheats quickly – the engine idles normally, but “suffocates” under load – the engine smokes heavily, power decreases after
In some situations, it is better to seek professional help and take the saw to an authorized service center. But with some faults you can also cope with yourself.
As a rule, in order to eliminate the root cause, you must first correctly identify it. Otherwise, the entire repair is tantamount to shooting sparrows with a cannon, or perhaps even shooting “invented” sparrows, since the breakdown may not be every.
If you try to start the chainsaw, but it does not start and at the same time does not make strange uncharacteristic sounds (knocking, grinding), then you just start it wrong (when you jerk the chainsaw. The chainsaw for a long time on the suction, the internal combustion engine is filled with gasoline, after which it is difficult to start).
How do you start a cold engine? 1. Push the lever or switch to the “choke closed” position. 2. If the model is equipped with a fuel pump, pump the fuel mixture into the carburetor. 3. Pull the starter knob until resistance is felt, then pull vigorously in amplitude and take your hand aside (2-3 times). There is no need to try to “pull” the starter rope out of the chainsaw! The saw should start and then stop. 4. If the engine doesn’t start, put the lever in the half throttle or work position and try to start the chainsaw in this mode. Note: some models have an ignition switch, make sure it is on.
What to do if the engine does not start? First, unscrew and inspect the spark plug. There are times when starting a chainsaw in cold weather when fuel mixture accidentally gets into the combustion chamber. In this case you should also unscrew the spark plug, dry the combustion chamber by idling, clean the spark plug and try to start the saw again.
How do I check the spark plug? With a twisted spark plug connected to a high voltage wire that is placed on the cylinder and pulled with the starter. Be careful! Do not touch the spark plug with your hands during this procedure! If you see a blue spark, the spark plug is fine. Screw the spark plug back in and try to start the saw again. If again there is a problem, check the connection of the high-voltage wire from the spark plug, the coil and the ignition system.
By the condition of the spark plug you can understand what’s wrong with the saw:
- The spark plug is dry. It’s obviously not getting into the cylinder. The problem is not the spark plug, so pull the spark plug back out. And we check the fuel system.
- Wet, heavily fuel stained spark plug. The cause of the excess fuel is either due to improper operation of the model or improper carburetor adjustment.
- The spark plug is covered with a black deposit. This may indicate the use of poor quality oil (so use only original oil for your saw), an improperly installed weight or an improperly prepared fuel mixture. The spark plug should be washed, the carbon injectors should be well cleaned with an EVEL or needle, and the electrodes should be wiped and sanded down.
When checking the plug, pay attention to the gap between the electrodes (should be 0.5 – 0.65 mm). A worn gasket should be replaced.
Checking and Adjusting the Carburetor
The carburetor is set on special instruments at your service station. The angle of adjustment screws varies for each saw (see operator’s manual). It is not necessary to adjust the carburetor frequently, especially if you have purchased the saw from a reputable seller. All of our Husqvarna saws are sent to a service center before sale, where specialists install the revolutionary adjustment.
Sometimes, however, the adjustment screws become loose.
Causes of chain saw misalignment:
- Severe engine (piston) wear. In this case, it is necessary to use a larger volume to repair the engine. However, adjusting the carburetor can improve the functionality of the saw for a period of time.
- A clogged carburetor is caused by a damaged air filter, the use of low-quality gasoline and the formation of scale. In such a situation, in addition to carburetor adjustment, it will be necessary to flush the carburetor.
- Severe vibration of the saw or damage to the blade guard. It happens very rarely, but it does happen.
Signs that indicate the need to adjust the carburetor of a chainsaw:
- The engine either won’t start or starts and then shuts off. This is due to the use of a bad fuel mixture.
- Significant increase in fuel consumption and exhaust emissions. An increase in exhaust gas volume indicates that the fuel is not being burned completely. This may be caused by fuel oversaturation.
The carburetor adjustment scheme for different chainsaw models differs and is described in the instruction manual. However, the general principle remains the same: it is necessary to change the quantity and quality of the fuel mixture fed into the engine cylinder.
Three screws help us adjust the carburetor:
- “L” – low for setting the low rpm
- “H” – high for high revs
- “T” (“La”, “S”) – for setting the idle speed (models with one screw have exactly “t”).
When adjusting the chainsaw carburetor, the following rules must be observed:
- Make sure you are pointing the saw chain in the opposite direction
- Place the saw on a level surface, the cutting part must not touch any objects.
Please note: The instructions show the exact angle of the adjusting screws. Accurate adherence to the instructions prevents damage to the engine.
The carburetor adjustment process itself consists of two points: Basic (with the engine not in use) and Final (with the engine warmed up).
Basic carburetor tuning
Slowly turn the maximum and minimum revolutions adjustment screws (H and L) all the way clockwise and then turn a turn and a half in the opposite direction.
Last carburetor adjustment
First warm up the engine for 5-10 minutes (not at high rpm).
Set the idle speed.
Now set the minimum number of revolutions counterclockwise, at which engine operation is stable, by adjusting the idle speed screw (T, LA, S) counterclockwise. The chain should not move. If the engine stops at idle, turn the idle screw accordingly. If the chain moves, turn the screw clockwise.
For final carburetor alignment of the chainsaw, check the engine for acceleration and top speed.
Keep pressing the accelerator pedal and observe how quickly the engine gains momentum from idle to maximum flow. If the engine slowly picks up the dynamics, you need to loosen the L (low RPM) screw and turn it slightly counterclockwise (not more than 1/8).
Setting the Maximum RPM
As mentioned, the maximum RPM is matched to the H screw, turning it clockwise increases the RPM and turning it counterclockwise decreases the RPM.
The highest rotational speed of a chainsaw is between 11,500 and 15,000 revolutions per minute, depending on the model. A higher speed is dangerous for the engine because it does not allow it to start. You can tell the maximum rpm by the ignition interruption. If at all possible, turn the H screw counterclockwise.
Check the chainsaw at idle.
Once we’ve adjusted the acceleration and maximum rpm, once again check the engine’s idle performance. We’ll know we’ve adjusted the carburetor correctly if:
- The chain does not move at idle
- The engine picks up speed
- The sound of the engine running is similar to the sound of a four.
If at least one of these conditions is not met, the adjustment should be restored (no baseline).
Check the muffler
Don’t underestimate the destruction of this chainsaw assembly. When the muffler closes, the saw loses power and, of course, will not start. If the muffler is collapsible, disassemble it, inspect it and remove the entire carpet. In some models, the muffler must be discharged and then dried with a hair dryer.
Please note: the muffler contains carcinogens hazardous to human health, dry cleaning is unacceptable, as it can lead to inhalation of these harmful substances.
When we remove the muffler, a clean rag is inserted into the engine exhaust port. Reasons why the muffler can get clogged are:
- Using the wrong fuel mixture (too much oil)
- Use of unsuitable oil (oil not suitable for two-stroke engines or poor quality oil)
Malfunction of the chain lubrication system in the chain saw.
What kind of chain lubrication system malfunctions?
- No or little oil flow
- Oil leakage
In the first case, we’ll first inspect the channels that carry the oil to the tire and clean them. Clogging is quite common.
If there is significant oil flow (slight oil damage is normal in all gasoline saws) we should check the oil pump tubing and fittings for leaks. Tubing may be loose or even cracked. Tubing leaks can be repaired by replacing or sealing with sealing material.
As for the oil pumps, in different models of chain saws, they can be of different design, the drive is also carried out differently (usually the drive is carried out by a drive sprocket or special equipment on the crankshaft). If the problem is related to the oil pump, then usually you do not need a complete replacement of the entire unit. It is enough to replace its moving part (pistons) and sawdust.
The most serious damage is a crack on the oil pump housing. In this case, it must be completely replaced.
Chain brake doesn’t work
The chain brake can fail if the liner and brake band are contaminated with grease and sawdust. The chain brake also does not work because the brake band is worn. If the belt is soiled with sawdust – you must clean the sawdust from the liner and replace the belt with a new one.
How can I avoid premature breakdowns? Tips for chain saw maintenance
Your main helper should be your instruction manual. If you lose it, ask your chainsaw service provider for an electronic manual.
Before you start the chain saw each time, make sure the chain is working, the teeth are sharpened and the tension is good (no sails, but not too tight, it is easy to detach the chain from the blade).
The chain can be sharpened on a special machine or with a file with a special template (there are different templates, depending on what pitch on the chain tooth).
Every time after use, the chainsaw must be cleaned: the chain, bar, air filter, housing, radiator ribs, cracks and other grooves are cleaned of sawdust. After using the saw, turn the bar so that the wear is even, lubricate the sprocket (if there are lubrication grooves in front of the saw).
When storing for a long period of time, pay attention to the fuel and oil released! The chain and bars form an electrochemical pair, as they rust together, they should be stored separately.
Chainsaw malfunctions. Major malfunctions, troubleshooting, reviews
Chainsaws are simple in design and working units. With proper handling, malfunctions are rare and often quickly eliminated by the owner.
Our review should help in extreme situations when you need to understand and troubleshoot the root causes of a tool malfunction.
Warranty returns and post-warranty service
Chainsaw owners who just received a new tool in the morning, unpacked it and assembled it according to the instructions, but could not start or were able to start and immediately spoke out. Be warned at once – do not try to disassemble the new engine and do not cancel the warranty stickers. Under such circumstances, it is best to replace the faulty chainsaw with another or seek warranty repair.
In accordance with the laws of most countries (including Russia and Ukraine), electric and chainsaws must be found to have faults not specified by the seller.
When purchasing a chainsaw from a seller, find out when the manufacturer offers warranty service. In most cases, 1 year to 36 months of use of the tool is specified.
In addition, the buyer can reduce the price of the defective product and reimburse the cost of repair or refund for the defective tool. During the warranty period, the owner of the chainsaw can only claim it if all the conditions specified in the warranty are met. As a rule, the buyer is given 14 days to identify all malfunctions and defects and to contact the seller.
The chainsaw will not start: the main reasons
Before running with the return to the seller or carry the chainsaw to the warranty repair shop, let’s try to understand the main reasons why the engine does not start.
So, you are the happy owner of a new tool, after you decided to unpack and assemble, check how the engine starts and fix the starter handle. And then some owners are in for an unpleasant surprise – a cold engine refuses to start. What can be the reason?
The main reasons when the chainsaw does not start with the onset of cold weather:
- Lack of fuel. Here it’s easy: Prepare a fuel mixture and try to start the chainsaw.
- Fuel quality problems. The truth is that all manufacturers indicate in their manuals that a certain type of fuel consumes a certain engine. Generally, the fuel mix is made with Hochoktan gasoline, AI-92, 95 and high quality air-cooled two-stroke engine oils. We also recommend that you monitor whether water has got into your fuel. If so, replace the fuel mixture with a fresh one.
- The saw does not start because of a false operator action. It is important to follow a certain sequence when starting a cold engine:
- Close the air damper to enrich the fuel mixture.
- Use a trotle primer on the system. If your chainsaw is not equipped with a primer, skip this point.
- Turn off the ignition (many inexperienced users forget this simple but necessary procedure);
- Without excessive effort and slowly pull the starter knob for the first “set” of the engine. It is important not to miss this moment, otherwise you can “flood” the engine.
- Open the choke;
- Start the chainsaw;
- Incorrect, overloaded or wet spark plug. Loosen the spark plug, make a visual inspection of it. If there is mist or moisture on it, clean and dry the spark plug. Try replacing the spark plug and start the chainsaw.
- Prolonged downtime. Your chain saw may not start or may start and stall after a long period of downtime. First remove the old fuel mixture (if there is any left in the tank) and refill it. It is also a good idea to check the function of the spark plug and make sure there is no fuel leakage.
- engine malfunction. If all the above manipulations did not give the desired result, and the chainsaw still does not start, then it should be stated that you have problems with the engine.
If these tips did not help, and the tool is brand new, take it to the store. Repair can be done at home, but it is better in specialized workshops.
Does not start on hot
Before you go to the workshop and find out the possible problems of the engine, it is worth finding out in which cases the chainsaw may not start when the engine is hot.
The main reasons when the chainsaw does not start on a hot engine:
- Spark plug. Here, as in the case of the cold engine, the cause of a bad start may be the spark plug. It is important to use only quality spark plugs and make sure they are clean and in good condition.
- No spark. No spark on the spark plug contacts when the starter is running. Check that the spark plug cap is tight against the spark plug, check the coil, and check that the clearance between the flywheel and coil contacts is correct. Adjust the gap and press the cap onto the spark plug;
- Fuel system malfunction. Check fuel filter, clean or replace if necessary. Check that the fuel hose is securely fastened. If you can’t visually see why your chainsaw will not start, the carburetor may be faulty.
- Muffler malfunction. The chainsaw will not start if the muffler is clogged or faulty. In this case, it must be cleaned of cinders, debris and debris or replaced with a new one.
- A “clogged” engine. One of the most common reasons a chainsaw won’t start. If the carburetor is not properly adjusted or the starting sequence is not right, the engine can “flood,” meaning too much fuel enters the cylinder.
- Tilt the chainsaw so that the spark plug hole is facing downward;
- When you work with the starter (make 8-10 strokes) excessive gasoline will flow out of the hole.
- After that wipe the spark plug dry, screw it in and try to start the engine.
A simpler way to start the flooded engine:
- Unscrew the spark plug and check its condition. Wet means primed: dry means flipped off;
- Fully open the choke;
- Press the gas to maximum;
- Start the engine. After a few tries with the starter, the excess fuel will flow out through the exhaust and the saw will start. It will probably stall soon – then we continue our efforts for a while longer;
it starts, but stops right away.
You have carried out all the preliminary steps correctly but immediately after starting the chainsaw would stop when idling or trying to add gas. What happens to your tool and why does the engine quit?
The main reasons when a chainsaw starts and then immediately shuts down:
- Insufficient fuel in the system. When the chainsaw is tilted, the fuel mixture collects in a certain place in the tank and doesn’t get into the carburetor, causing the saw to stall. This is a fairly simple defect that you can easily fix – just add fuel to the tank.
- Faulty blower. Often the chainsaw stays because the vent is blocked, then the fuel comes in less than it should. Take the needle and gently, without much effort clean the part, start the engine and check whether it stops at different speeds.
- The air filter is dirty. At high loads and high RPMs, the engine does not get enough air and simply stalls. It is recommended to clean the air filter daily after finishing work;
- Pump and fuel filter malfunctions. Not enough gasoline is getting to the carburetor and causes the saw to stop when you press the accelerator pedal;
- Lubrication system. If the lubrication system is missing or inadequate, your chain saw may be idle. Fill the oil tank, check the oil pump and oil line.
- The engine sneezes, shoots and stops. In this case, the chainsaw also needs a fresh fuel mixture and may sneeze and stop due to a faulty carburetor.
- Insufficient contact between the wire and the spark plug. Deterioration of contact is due to mechanical impact or ash buildup and combustion. Eliminate the problem or your chainsaw will not start or stop;
- Failure of the piston group. An extremely unpleasant reason for an engine to stall. Since the engine has a complex device, you can not do without the help of an experienced technician.
Chainsaw maintenance includes:
- Pay attention to the quality of the gasoline and oil you use to make the fuel mixture. Follow the correct proportions;
- Do not use fuel that is more than two weeks old. Check and clean the gasoline and oil tanks regularly or the engine will stall or the saw will not start;
- Clean the air filter regularly. The air filter is a simple device and this process is not demanding;
- Turn the bar every time you sharpen the chain to extend the life of your saw;
- Check and clean the oil inlet and outlet holes, oil channel and guide bar groove. Remember that your saw starts or stops when the automatic lubrication system fails.
Carburetor repair overview
Evaluation: chainsaw starts and stops. Reverse air intake into the tank
Review: Doesn’t start, starts and stops: how to fix it?
How to fix it?
Ivan Samoilov, 38, Amur region
“My Chinese saw does not start well, in general you can say that it does not start, because it stops immediately. I start it by quite complex manipulation, it runs with full throttle and for a while stalls. However, after a while it starts sneezing and starts itself – it’s impossible to operate. I spent a long time fiddling with it myself, and then brought it to the shop. It turned out that the magnet worked – I never thought I’d blame it on the carburetor.
Ivan Vesnin, 33, Solnechnogorsky district
“After winter I decided to walk in the garden with a chainsaw. All of a sudden it went well, turned out fast enough, after the apple warmed up, and then started to stand. Runs for 8-10 minutes and stands. And not only under load, but also at idle. I was already frightened – decided that it was time to change the piston. Then I thought: let the breather clean me up. Worked for an hour – sucks fine, even picks up revs quickly, starts up with half a bang, what let stand – completely forgets. That’s the kind of teething problems. “
Yakov Baulov, 59, Siberian Federal District
“After a long downtime (didn’t go near it all winter) the chainsaw began to stand on high rpm and with a sharp ride. It seems to pick up, but if at some point you add gas, it stops. It didn’t start well to begin with, but I made a carburetor and it seemed to get better. Long story short, it took me a very long time to find the problem, until I got into the gas tank and discovered that my chainsaw has no fuel filter – only the edge of the fuel line. That’s a total bummer – how can a unit like that come out of the system. I have now repaired it – it worked fine, won’t do that again. Barking and crying – where is this world going. “