The Mower Will Not Start
The lawn mower will not start, or starts but stalls The lawn mower will not start, or starts but stalls. What is the reason?
The lawn mower won’t start after winter
In such cases, the unit must be serviced. Remove the fuel system, including filters (air, fuel), disassemble the carburetor, clean and rinse each unit. Blow out the filters with air. Pay attention to fuel quality and octane number.
It should be borne in mind that products of such well-known companies as STIHL, Husgvarna and other brands will not run on cheap gasoline with a low octane number.
Suitable fuel for them is from the AI brand. 92 and higher from car gas stations and then from well-recommended ones, since there is also bad gasoline at gas stations. The use of high-octane and high-quality gasoline will determine how long the lawn mower will be used and how long it will last.
It is necessary to take into account one more fact that with a long storage of a diluted fuel mixture, its working qualities fall, which also leads to consequences in which the lawn mower does not start. Therefore, it should be diluted in portions, that is, the amount of the mixture that is produced at a time.
The operating instructions clearly describe and explain the mixing ratio of gasoline and oil. Strict adherence to the correct proportions will at least save you from several questions about why the lawn mower won’t start and what to do in such cases.
The lawn mower will not start, the spark is gone
The loss of a spark entails checking the contacts and the correctness of the gap between them, the conducting wires to the candle and the candle itself.
The way to check the spark is to unscrew the candle, connect the wire to it, put the candle sideways to the motor casing and pull the starter several times as if starting the lawn mower, while looking at the coal and the contact of the candle, a spark should run between them.
If there is no spark, take a new candle, follow the same procedure, if the spark cannot be traced, then there is a problem in the wire or contacts, it is better to replace them.
The lawn mower will not start, or will start but stalls. What is the reason?
To understand this, you need to know the principle of operation of the unit as a whole. It also happens that, just bought, a new saw does not start, and it starts running around the service centers, in such cases it is recommended:
Carefully read the instruction manual;
to study in detail the method of first starting and running in lawn mowers;
try to understand how the product works;
how gasoline is pumped up and so on.
Causes of malfunctioning lawn mowers:
The quality of gasoline is poor;
incorrect proportion of gasoline and oil;
clogging of the fine filter;
the spark was gone.
Determine the availability of fuel and its supply.
First, you need to make sure that there is a fuel mixture in the tank of a chainsaw that does not want to start, and it regularly enters the carburetor. With a full tank, we check how the mixture is fed through the gas line. Disconnect the fuel system pipe from the carburetor and try to pump it up. In the case of a complete order, when pumping, gasoline will be supplied in jerks in accordance with the standards set by the manufacturer. Poor or no fuel supply can result from:
- The fuel supply channel is clogged;
- Clogged fuel filter.
Often the reason for a poor start of the chainsaw can be a tank that is too full. In this case, you should pay attention to the presence of smudges under the saw case cover. If present, see the connection of the gasoline feed pipe to the carburetor. Most often, it is squeezed out by pressure when the tank cap is screwed on, filled up to the very neck, which prevents the engine from starting.
The quality of the fuel mixture can also be one of the reasons why the chainsaw does not start. If, after completing the work, the remaining gasoline is not drained, and the tool is left for long-term storage (more than 2 weeks), then the processes of resin formation and polymerization of components will begin to occur inside the tank. Which can cause carbon deposits on the piston, rings and cylinder liner. Therefore, always prepare the mixture only in the required amount before work.
Checking the condition of the fuel and air filters.
If everything is in order with the fuel quality, the chainsaw engine may not start due to clogged fuel and air filters. To diagnose these elements, it will be necessary to perform a number of manipulations associated with their dismantling.
For the fuel filter:
- Disconnect the gasoline supply channel from the carburetor;
- Pump up fuel.
If there is little or no pressure in the pipe, disconnect the filter. Before this, free the tank from the mixture and remove the filter element itself. Dismantling is done with a wire hook. A clogged replacement cartridge that causes a poor starting of the chainsaw engine can be cleaned, but it is best to replace it with a new one. When using the tool in dusty conditions, it should be cleaned on a regular basis.
A clogged air filter can cause the chainsaw engine to run erratically, making it stalling or difficult to start. Dust and dirt deposited on the adsorbent material impede the flow of air into the system, make the fuel mixture so rich that it will sometimes be difficult to start the tool.
Checking the air filter is one of the first steps in finding the cause of a poor start.
Care should be taken when removing the air filter, as dust accumulated on the surface of the saw during operation can enter the carburetor. And this is fraught with more expensive repairs. After detaching the cartridge, thoroughly clean it from the accumulated dirt and rinse it with the addition of detergent. Dry the element and place it in place just as carefully.
Checking the outlet of the chainsaw.
One of the reasons that a chainsaw does not start well may be a clogged exhaust channel or its muffler. At the same time, a drop in power is noted in the process of sawing sawn timber and logs. This is most often due to resinous deposits on the spark arrestor or muffler channel, which are formed during the combustion of a poor-quality mixture of gasoline and oil, which impede the removal of exhaust gases.
Resonator clogged with carbon deposits can cause poor starting of the gasoline saw.
Eliminate the reason for the poor start of the chainsaw, in this case, you can remove the accumulated combustion products. To do this, perform a number of manipulations:
- Remove the muffler by unscrewing the screws;
- Remove the cooling panel and gasket;
- Remove the spark arrester;
- Disassemble the resonator housing;
- Wash all elements from carbon deposits with detergent;
- Let them dry completely;
- Collect everything in reverse order;
Why does the petrol trimmer stall
A scythe with a gasoline drive is a useful thing for owners of home gardens, lawns, and when the trimmer suddenly stalls, the work to clear the area from grass stops. The device itself is a rather complex mechanism, so there are many different reasons for its breakdown. The most common problems are contained in the operating instructions. You should know the reasons why the trimmer stalls in order to effectively repair the device yourself.
At high revs
When the scythe stalls at high speeds, this is due to the following problems:
- Clogging or sticking of the valve located on the gas tank cap;
- The carburetor is out of alignment under the influence of vibrations arising during the operation of the mechanism;
- Problems with the circulation of the fuel mixture;
- Suction of atmospheric air;
- The fuel intake hose is cracked or loose.
Carburetor adjust, referring to the trimmer operating instructions. For adjustment, it is often sufficient to loosen the tightening of its housing. If there are problematic points with the circulation of the fuel mixture, then it can gradually enter the carburetor. After its development, the engine stalls at high speeds.
When heated
The lawn mower often stops when it heats up. At the same time, it starts up, works “jerky” and gradually stops. This process occurs when gasoline in the carburetor boils or the damper in it is installed in a rotary, and not disk type. In the latter case, the part is changed.
It happens that the trimmer heats up if damaged ignition circuit wire or a coil. In order for the device to start working normally, parts are replaced.
We carry out diagnostics of a candle and a candle channel
If the quality of the fuel mixture is not in doubt, and the lawn mower stalls when started, then a flooded candle may be the cause. Here, for repairs, an ordinary spark plug wrench (probably every motorist has) and a spare candle are suitable.
- We unscrew the candle and wipe it;
- Dry it thoroughly (do not ignite);
- We drain the excess fuel in the chamber through the spark plug hole and dry it;
- We clean the old candle from carbon deposits using a file or a lady’s file;
- We expose a gap with a distance of 1 mm (you can check with any coin);
- We put everything back in place and try to start the trimmer.
If the candle is working, the socket where it is located is completely dry, and the lawn mower does not want to start, lubricate the threaded connection with gasoline. It should be slightly damp. No matter how wonderful a spark the candle may give out, there is simply nothing to ignite in a dry chamber.
If the trimmer motor still does not start, you should exclude such a reason as the absence of a spark due to poor contact between the spark plugs and the high-voltage wire. If the connection is of good quality, but there is still no spark, most likely, your ignition unit has “flown”. Here it will not be possible to do without a master, since the part is not repaired, but sold as a single unit.
Why the lawn mower won’t start. Troubleshooting
Caring for a personal plot, summer residents periodically encounter the fact that the lawn mower does not start. There are many reasons for tool failure. For the correct diagnosis of the problem, the owner of a useful unit in the country needs to know the device and the principle of operation of its individual parts.
- How to start diagnosing lawn mowers
- Checking the fuel mixture
- We carry out diagnostics of a candle and a candle channel
- Lawn mowers filter diagnostics
- Breather and exhaust port
- Complex reasons for lawn mowers failure
- Rules for the operation and storage of lawn mowers
Complex reasons for lawn mowers failure
If the step-by-step troubleshooting algorithm does not work, and your scythe still does not start or stalls, it is worth inspecting the carburetor and the engine itself. A clogged carburetor can be one of the reasons for erratic tool performance. There are three main problems here:
- Clogged ducts or nozzles. All this is cleaned by special washes or blown by a powerful jet of compressed air from the compressor. Do not use needles and wires, as the bore may be damaged;
- Worn carburetor gasket. Exit. Replacement of a failed gasket;
- Violation of tightness. To check this indicator, you can use an ordinary household tonometer, replacing it with a suitable pressure gauge. Watch the readings: if they do not change, everything is fine, and if the pressure starts to drop, then some part of the carburetor is faulty. We’ll have to find it and replace it with a new one.
If everything is in order with the carburetor, then the petrol trimmer may not start due to wear of the piston group. If chips, scratches or scuffs are found, the piston or cylinder should be replaced. Piston rings are subject to mandatory checks. A small backlash of the piston when rocking the connecting rod indicates that it is time to change the rings. It is best to entrust this procedure to the specialists of the service center.