A long break in the operation of a gasoline tool often causes problems with starting, and Husqvarna chainsaw is no exception. The owner may encounter the fact that the equipment refuses to grasp, stalls immediately after start, or shows no signs of life at all. This occurs due to natural physical and chemical processes occurring in the fuel system and cylinder-piston group during idle time.
The main cause of difficulties is usually the loss of volatile fractions of gasoline and oxidation of the oil, which leads to the formation of a tarry coating. If you left your equipment with a full tank for the winter without preservation, the likelihood is that Husqvarna It won't start the first time, it tends to be one hundred percent. However, it’s too early to panic: in most cases, the situation can be corrected with your own hands, without contacting a service center.
To successfully resuscitate the instrument, it is necessary to act sequentially, checking each engine life support system. Sparking, compression and quality of the fuel mixture are the three pillars on which the operation of your unit rests. In this article we will analyze a detailed algorithm of actions that will help return the saw to operation even after several months of inactivity.
Primary diagnosis and visual examination
Before pulling the starter, it is necessary to conduct a thorough visual inspection and a basic check of the components. Often the reason is simple: the fuel hose is pinched, the air filter is dirty, or the throttle settings are off. Visually assess the condition fuel tank and the integrity of the housing - the presence of cracks may indicate a leak in the seal.
Pay special attention to the air filter. If it is clogged with sawdust and dust, the engine will choke without receiving enough air to create the correct air/fuel mixture. Remove the filter cover and check its condition: if the material is blackened or saturated with oil, it must be replaced or thoroughly washed (if it is reusable).
Also check the condition of the spark plug by unscrewing it with a special wrench. Carbon deposits on the electrodes will tell you a lot about the operation of the engine before it was idle. Black dry soot indicates work at enriched mixture, and oily - about problems with the piston rings or excess oil in gasoline. A whitish tint indicates overheating or running on a lean mixture, which is dangerous for Husqvarna.
Working with the fuel system and mixture
The most common mistake made by users is storing the saw with old fuel residues in the tank and carburetor. Gasoline tends to evaporate, leaving behind heavy fractions and resins that clog the jets. If the saw has been sitting with fuel for more than a month, the first step is to completely drain the remaining mixture through the fuel filter.
⚠️ Warning: Never try to start an engine with old fuel, even if you dilute it with fresh gasoline. Oxidation products can completely damage the carburetor membranes and coke the piston.
After draining the old fuel, it is recommended to blow out the tank with compressed air or simply shake it well to remove any remaining liquid. Then prepare a fresh fuel mixture, strictly observing the proportions specified in the instructions for your model Husqvarna. Typically this ratio is 1:50 (2%) when using quality synthetic two-stroke engine oils.
Use only fresh gasoline with an octane rating of at least AI-92 and do not store the finished mixture for more than two weeks. Old oil in gasoline loses its lubricating properties, which can lead to cylinder scuffing and destruction of crankshaft bearings. Pour the prepared mixture into a clean tank and shake the saw vigorously several times to mix.
Use only specialized 2-stroke engine oil marked JASO FD or ISO EGC. Regular motor oil for cars is absolutely not suitable and will lead to the failure of the saw.
Checking the ignition system and spark plugs
If you have sorted out the fuel, but the engine is silent, the next step is to check the spark. Unscrew the spark plug, put the tip of the high-voltage wire on it and press it tightly with the metal thread to a clean metal part of the cylinder (ground). Pull the starter sharply and look at the gap between the electrodes.
A bright blue spark indicates serviceability ignition systems and the ignition module. If the spark is red, weak or absent altogether, the problem may lie in the spark plug itself, carbon deposits on the insulator, or a faulty coil. Try replacing the spark plug with a new one, selected strictly according to the spare parts catalog for your model Husqvarna.
Why does the spark disappear?
The spark may disappear due to a breakdown of the spark plug insulator, a break in the high-voltage wire, or failure of the electronic ignition module (magneto). Another common cause is flooding the spark plug with fuel, when wet electrodes cannot create a spark.
Pay attention to the color of the central electrode insulator. Brick brown or gray-brown color indicates normal engine operation. If the insulator is covered with a black velvety soot, it means that the mixture was too rich, or the oil did not have time to burn. In this case, it is better to replace the spark plug before starting, since carbon deposits can cause glow ignition.
Purge the cylinder and eliminate flooding
A common situation after long attempts to start is a “flooded” spark plug. The fuel washes away the lubricant and prevents a spark from forming, and excess gasoline in the combustion chamber does not allow the piston to create the necessary compression. To eliminate this condition, it is necessary to dry the cylinder and spark plug channel.
Unscrew the spark plug and turn the saw over with the spark plug hole facing down. Pull the starter vigorously several times to remove excess fuel from the cylinder. Wipe the candle with a dry rag or heat it over an open fire (if it is not possible to replace it), removing carbon deposits and remaining moisture. Reinstall the spark plug, but do not tighten it all the way yet.
☑️ Algorithm of actions when a candle is flooded
After drying, try starting the engine without closing the choke. If the engine catches and starts running for a couple of seconds, this is a good sign. If after drying there is a spark, the fuel is fresh, but the saw still does not start, the compression may be broken or the carburetor needs to be adjusted.
Carburetor adjustment after inactivity
Prolonged downtime could lead to changes in carburetor settings or sticking membranes. The standard factory setting is usually indicated by the position of the screws L, H and T. Screw L is responsible for low speed, H for high speed, and T (or LA) for idle speed. Before making adjustments, make sure the air filter is clean and the exhaust ducts are not clogged.
Start the engine and warm it up for 5-10 minutes. If the saw stalls when adding gas, the mixture may be too lean (too much air). If it smokes and growls, the mixture is too rich. Adjustment should be made carefully, turning the screws 1/8 or 1/4 turn, observing the engine response.
| Adjustment screw | Function | Direction of rotation (enrichment) | Rotation direction (lean) |
|---|---|---|---|
| L (Low) | Mixture quality at low speeds | Counterclockwise | Clockwise |
| H (High) | Mixture quality at high speeds | Counterclockwise | Clockwise |
| T / LA | Idle speed | Counterclockwise (increase speed) | Clockwise (lower speed) |
The ideal setting is achieved when the saw confidently picks up speed when you press the gas trigger, does not stall at idle and the chain does not spin in place. The factory settings of the screws often have plastic stops that prevent them from being turned into dangerous areas, but after removing the stops, the range of adjustment expands.
Technique for proper starting of a cold engine
Many users ignore the starting algorithm, which leads to rapid wear of the starter and the inability to start working equipment. For cold engine Husqvarna There is a clear sequence of actions, which is not recommended to be violated. First engage the chain brake by moving the handle forward until it clicks.
Move the combination control lever to the cold start position (up position, often indicated by a choke symbol). Press the decompression valve (if your model has one) to reduce cranking resistance. Lightly press the throttle trigger and lock it in this position by engaging the idle lock.
Starting Key: Don't keep the starter in the down position for too long. As soon as the engine “sneezes” or tries to seize, immediately move the throttle to the middle position to warm up.
Place the saw on the ground with your right foot on the rear handle. Hold the body with your left hand, and with your right hand sharply and firmly pull the starter handle. Do not remove the cord completely - let it return to its original position. As soon as the engine tries to start, move the choke lever to the middle position and repeat the start. After the start, give the gas to reset the idle speed.
Common problems and their solutions
Even if all instructions are followed, specific problems may arise. If the saw starts and immediately stalls, check the fuel filter in the tank and the tank breather. A clogged breather creates a vacuum, and gasoline stops flowing into the carburetor. Clean the breather hole with a thin needle.
If the engine runs rough and loses power, the muffler or spark arrestor may be clogged. Carbon deposits that accumulate over years can completely block the exit of exhaust gases. Remove the muffler and inspect it: if clogged, burn off the carbon deposits or replace the part.
⚠️ Attention: Operating the engine with a clogged muffler or spark arrester leads to overheating of the piston group and burnout of the piston. Operating the saw in this condition is unacceptable.
If the starter turns too easily, as if there is no compression, this may indicate a serious breakdown of the piston group or crankshaft seals. Compression diagnostics are carried out with a special device, but it can be indirectly assessed by the force on the starter. If the saw does not compress air, a major overhaul will be required.
What to do if the saw smokes white smoke?
White smoke during operation is normal for a two-stroke engine as oil is being burned. However, if the smoke is billowing and has a strong burning smell, there may be too much oil in the cylinder or the carburetor settings may be incorrect (the mixture is too rich).
FAQ: Frequently asked questions
Is it possible to store a Husqvarna chainsaw with a full tank?
Strongly not recommended. The fuel oxidizes, loses its properties and forms resins that clog the carburetor. The saw must be stored for storage with exhausted fuel, starting it until it stops completely.
What octane number of gasoline is best to use?
For modern saws Husqvarna It is recommended to use AI-92 gasoline. Using AI-95 with a large amount of additives can lead to overheating and detonation, which will shorten the engine's life.
Why does the saw stall when you press the gas?
Most likely, the adjustment of screw L (low speed) is incorrect or the fuel filter is clogged. The cause may also be air leaks through the seals or gaskets, which leans the mixture.
How often should the fuel filter in the tank be changed?
It is recommended to change the fuel filter every season or every time you replace the saw set if you actively use the tool. A clogged filter creates resistance to fuel flow.