Petrol Braid Won’T Start

6th August 2020

How not to get confused if the lawn mower won’t start
The scythe does not start during the harvest. Troubleshooting and remedies. Do-it-yourself repairs and in specialized centers. Instrument operating rules.

How not to get confused if the lawn mower won’t start

The tool, despite its small dimensions, is a complex technical device. If you study the operating instructions, it turns out that the reasons why the lawn mower does not start are known and removable. It is necessary to consistently eliminate factors that make it difficult to start the tool. Usually start with more accessible nodes with an easy health check.

Troubleshooting

All the reasons why the lawn mower does not start can be classified according to the specifics of the operation of individual units. In the service center, faults are classified:

Engine malfunction (piston wear, bearing malfunction, crankcase crack);
Malfunction of the fuel mixture supply. Clogged pores of the air filter or carburetor malfunction;
The ignition system does not work;
A mechanical malfunction. Leaking hoses, broken wires under the braid, ruptured pipes.

The user first needs to check if there is fuel in the tank. Start up in accordance with the instructions, with the saw on its side. Set the air damper to the “closed” position, pump up fuel, turn on the ignition and make 3-4 sharp jerks with the starter. If the engine is running, open the air damper. The lawn mower does not start. Repeat the operations with the air damper slightly open.

If the launch fails, we start looking for the reason for the failure:

Check fuel quality;
Make sure that the candle is working and the candle channel is clean;
Check the cleanliness of the air filter;
Make sure the fuel filter is not clogged;
Check the cleanliness of the breather;
Clean the outlet.

Complex reasons will be found during the diagnosis of malfunctions leading to overhaul of the carburetor. Such reasons include clogging of the internal channels of the carburetor, wear of the gasket on it and a violation of the tightness of the internal halls with a loss of vacuum. Do-it-yourself lawn mowers repair, if it won’t start, will take patience.

Adjustment and tuning of the carburetor

Maximum and minimum engine speed, smooth idle speed are controlled by the carburetor. The stable operation of the lawn mower depends on the amount of the supplied combustible mixture and air, their ratio. The lawn mower will not start if the carburetor adjustment is not correct. The procedure for adjusting the device for supplying fuel at low speed (L), high speed (H) and idle (T) is regulated by the screws of the same name:

The chainsaw should work for at least 10 minutes, since the adjustment is carried out hot.
Screw H is turned smoothly to maximum speed, then turned by ¼, counterclockwise, reducing the speed of rotation of the engine shaft.
Idling is adjusted with screw T, so that the scythe does not rotate.
The screw L is adjusted, at first opening the throttle to the maximum, and then smoothly reducing the speed to stable minimum.

After adjustment, a serviceable carburetor with cleaned filters and a checked ignition should ensure the engine is running. In the event of a carburetor malfunction, after repairing it, you will need to adjust the feed system again before starting the lawn mower.

Rare breakdowns that prevent lawn mowers from working can be:

Rewind spring failure;
Broken or stuck starter pulley;
Faulty starter assembly.

The most important malfunction, the elimination of which is associated with replacing the engine, may be the failure of the engine piston group. The cost of repairs will cost about 70% of the cost of the product. Understanding the reasons why the lawn mower won’t start will help:

The lawn mower will not start on a cold

When starting a cold engine, it is not recommended to press the gas. Tilting the mower so that the air filter is on top, press the fuel suction button 5-6 times, set the function switch lever to the “start” position, pull the starter cord several times until the engine starts. After a few seconds of running the motor, turn off the starting system.

The lawn mower starts and stalls. What to do?

1. There is a spark, and everything seems to be normal, but the mower will not start, in such cases you should check the air inlet valve to the fuel tank. A clogged valve leads to the creation of a vacuum in the tank, in which the carburetor does not receive enough gasoline, so the lawn mower will start, but then stall. To exclude this reason, you need to clean the valve and try to start the lawn mower with the tank cap not completely twisted.2. If this does not start the mower, remove and clean the fuel filter and check all carburetor parts, then try starting. The lawn mower will not start again, the air filter is disconnected, try to start without it, if the mower starts up, the reason is in the air filter, replace it.

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.

Lawnmower won’t start: causes and remedies

Diagnostics of the reasons why the lawn mower won’t start. A quick return to life of Chinese and domestic two-stroke internal combustion engine lawn mowers.

It happens that a two-stroke motor does not even show a flash in the cylinder, but sometimes it catches it and immediately stalls. No need to be sad, this Chinese commodity can be repaired right on the knee with a minimum of tools.

Before starting diagnostics, you need to make sure that the motor rotates with little resistance. If there is no compression in it, then the further is useless, and the piston needs to be changed (there is nothing complicated about this either, everything is like a designer).

The second is the carburetor

It is not necessary to disassemble the unit right away, especially if the engine stalls after starting or does not keep idling. Try changing the fuel first, it may contain an excess of oil. You can inject a purifier into the air filter, let the motor “shit” a little at maximum speed.

Next, we go in order. The air filter, the fuel filter (it can be outside and in the tank), the fuel pumping button, the integrity of the hoses. Gas tank cap. The ventilation valve may be clogged, the motor simply does not pump gasoline. Blow everything out. And it will work!

Be sure to. Look at the connection of the carburetor to the intake manifold! Elsi sucks air there and there is no tightness. Eliminate!

The dosing needle hangs up. Also a problem in some models. It is enough to push it down, or remove and grind it with velvet.

You can pull off the hose from the carburetor, see if fuel goes to it when pumping. It is clear that often to check it is necessary to remove the plastic sheathing, break your fingers on the latches, but anyway, sooner or later you will have to climb there.

The first is the candle

The first step is to unscrew the candle. If it is wet, the ignition system is faulty. Try to wipe off the spark plug, put it in the cap, attach it to the engine, pull with the starter. Is there a spark? If not, then you need to change the candle.

Replacing the spark plug didn’t help? Then you need to watch the magneto, cable, ignition coil. The cable is ringed, the coil is checked for resistance (the multimeter is in the resistance measurement mode at 200 Ohms, one contact to ground, the other to the output of the coil, should show from 0.4 to 2 Ohms).Sometimes the magnets on the flywheel get dirty, or the key is licked off, and the ignition moment flies away. Chinese shit throws up all sorts of surprises, but most of it can be revealed visually.

Be sure to pay attention to the plaque of the candle. If it is black, the candle is smoked, then the mixture is rich, or you have mixed the fuel incorrectly. If the plaque is white, it means that the mixture is poor, and the engine could already die of temperature. Ideally, the color should be brick, light, without much plaque.

Again, if the black candle is dead, you should not immediately sin on the carburetor and ignition. Screw in a new one, see what the plaque will be. Maybe the candle was just of poor quality.

Lawnmower won’t start: causes and remedies

Diagnostics of the reasons why the lawn mower won’t start. A quick return to life of Chinese and domestic two-stroke internal combustion engine lawn mowers.

Is everything whole, clean, working?

Trying to adjust. We take a long screwdriver, find the idle speed adjustment bolt (it is located on the throttle valve), twist it a couple of turns so that the damper opens slightly. We start. Does it work smoothly? Then let’s move on. Won’t start or stall? Opens the damper until it starts up stably.

Next, adjust the quality of the mixture with screw L. It is necessary to achieve maximum idle speed. Here the principle is reversed. The more the bolt is unscrewed, the richer the mixture. After that, the quality of the mixture is adjusted at maximum speed with screw H.

If the carburetor adjustment does not work, then it needs to be disassembled. Watch the membrane, clean the jets and internal passages. For this, it is necessary not only to have a repair kit, but also, preferably, a spare carburetor.

The second is the carburetor

Be sure to. Look at the connection of the carburetor to the intake manifold! Elsi sucks air there and there is no tightness. Eliminate!

The dosing needle hangs up. Also a problem in some models. It is enough to push it down, or remove and grind it with velvet.

Breather and exhaust port

Often, “gentle” branded lawn mowers do not start and stall due to a dirty breather. The main function of this element is to equalize the pressure in the gas tank. When this unit becomes clogged, a vacuum is created in the tank, which prevents the supply of fuel. You can eliminate the malfunction by cleaning the breather. You can use a regular needle for cleaning.

Normal operation of streamers with internal combustion engines can be disrupted due to dirt entering the exhaust channel or a clogged silencer mesh. There is such a problem on older generation models. The issue can be resolved by traditional cleaning and removal of the anti-spark grid.

How to start diagnosing lawn mowers

If the lawn mower does not start or immediately stalls after starting, it is necessary to sequentially check all the main components and assemblies. The verification algorithm is as follows:

Fuel tank (fuel quality);
Candle and candle channel;
Air filter;
Fuel filter;
Breather;
Outlet channel.

These nodes are most often the source of major problems that can be eliminated after a thorough inspection.

Checking the fuel mixture

Before starting the engine of the gasoline streamer, check the presence and quality of the fuel mixture. Do not save, do not be greedy and do not be clever in this matter. Repair or replacement of the piston group will cost you too much (sometimes up to 70% of the cost of a new tool). Prepare the oil-fuel mixture strictly according to the instructions. Calculate its amount based on real needs. Excess gasoline left over after work loses its quality over time.

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