Cause Trimmer Does Not Start

Carbon build-up in the muffler

Cause Trimmer Does Not Start

Before resorting to more serious repair actions, you must make sure that the exhaust channel is in good condition. This section does not apply to previously unused trimmers, as they have practically no output. If the lawn mower has been in operation for many years and during this time the unit has not been subjected to serious diagnostic measures, then it is imperative to check the fact that the muffler is clogged.

The accumulation of carbon deposits prevents exhaust gases from escaping, making it simply impossible to start the engine. Of course, one day the outlet can not get clogged, because of which such a situation must be preceded by certain signs. The exit of black smoke from the muffler is a kind of carbon deposit that gradually accumulates on the walls of the exhaust system. A significant increase in the sound of the installed engine may occur, which is associated with overcoming the enormous resistance of the exhaust gases to release them. When idling, the device spontaneously stalls. In critical situations, engine performance deteriorates significantly.

If there is serious dirt on the anti-spark mesh, then the reason for the impossibility of starting the trimmer engine may lie in the exhaust channel. It is necessary to clean the mesh as carefully as possible, since it is black soot that is a very dangerous carcinogen for humans, which can provoke respiratory tract damage. For cleaning, you should use specialized products that will cope with carbon deposits.

Reliability of built-in filters

It is these devices that often become an obstacle because of which the classic trimmer does not start. The filter provided by the manufacturers is responsible for the high-quality cleaning of the air entering the carburetor. Clogging of the cleaning unit is fraught with the fact that oxygen enters the internal compartment of the unit in a smaller amount or its supply stops altogether. It is possible to determine the malfunction of the air filter in a fairly simple and affordable way:

  • Dismantle the device and inspect it thoroughly.
  • If no blockages are found with the naked eye, then try starting the mower without a filter. Replace this part only if the trimmer has started successfully.
  • You can use compressed air to clean the air filter. But if the cleaning device has been used for a long time, then it is more advisable to replace it.

It should be noted that the trim tabs will not start due to a clogged air filter in the most rare cases. Most often, this device affects the stability of the engine. A more real reason lies in a clogged fuel filter. This unit is located in the tank of the unit. If the trimmer has been used for more than two years, then it is imperative to check the filter, which may interfere with the supply of fuel to the carburetor.

If the user is sure that the main problem lies in the fuel cleaning element, then the following steps need to be taken:

  • Remove the filter carefully.
  • Try to start a lawn mower.

If the device starts up quickly enough, then the problem lies precisely in the fuel filter.

Long-term storage of fuel in the involved tool tank, as well as accidental ingress of small debris and dust into the trimmer tank can significantly reduce the life of this unit. But if the filter is working and the mower still won’t start, then the fuel hose should be checked. Often there are situations when the hose together with the filter are disconnected from the main pipe, which necessarily leads to the impossibility of starting the engine.

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Since the petrol trimmer common today belongs to the category of effective and complex devices, it is imperative to study the attached instructions before using such a unit. Many users ignore the manufacturer’s recommendations. But sooner or later it becomes necessary to figure out why the trimmer does not start. In such a situation, experts recommend diagnosing the device.

Checking the involved fuel mixture

To understand why a previously serviceable trimmer does not start, it is necessary at the very first stage to evaluate the oil and gasoline used. The unit can function properly only thanks to high-quality fuel. The brand of gasoline must match the needs of the engine. If the device runs on low quality fuel, it is fraught with frequent failures in the trimmer. If this problem is not resolved in a timely manner, then as a result, a breakdown of the cylinder-piston system may occur. Elimination of such a breakdown often exceeds the cost of the unit itself.

Incorrectly prepared fuel mixture must not be poured into the mower. In the operating instructions for the device, manufacturers must indicate the exact proportions in which high-quality gasoline and mineral oil should be combined. It is not recommended to prepare the mixture in large volumes, since the loss of certain properties inevitably occurs during long-term storage. If the mower will not start, then the old fuel must be carefully drained off to be able to use the freshly prepared fuel mixture.

serious causes of malfunction

If, after a thorough examination of the basic trimmer units, the cause of the device malfunction has not been found, then you need to carefully inspect the engine and carburetor. In this case, three key problems can be distinguished at once, which are most common:

Natural wear of the installed carburetor gasket. The only logical way out of this situation is to replace the faulty part.

  • Accumulation of debris and carbon deposits in nozzles or channels. For cleaning, you can use only factory flushes or a normal stream of compressed air from the compressor. It is forbidden to use wire and sewing needles, as one wrong movement can seriously damage the flow area.
  • Loss of the previous tightness. To thoroughly check this indicator, you should use a classic household tonometer, having previously installed a suitable pressure gauge. It is necessary to monitor the indicators: if any fluctuations were not recorded, then everything is fine, but when the pressure gradually drops, then some part in the carburetor is out of order.
  • If the carburetor used is working properly, the petrol trimmer will not start due to the piston group being out of order. If during the inspection, characteristic chips, distortions or scratches were found, then the part must be replaced. Experts recommend replacing the piston rings. If, when rocking the mounted connecting rod, a slight play occurs, then the rings must be replaced, but this procedure is best entrusted to professionals.

    Petrol trimmer: what to do if the lawn mower won’t start

    The lawn mower stalls when you press the gas

    Gas key lawn mowers

    Hole in the fuel cap (breather) of the trimmer

    Lawn mowers fuel valve

    With a similar problem, you should pay attention to the fuel valve, which, when clogged, ceases to normally pass the fuel mixture. The solution to this problem is to mitigate it with a suitable tool. In addition, a problem with the circulation of the fuel mixture may lie in a dirty valve. To do this, it is enough to blow it with a stream of compressed air.

    Trimmer stalls: causes and troubleshooting

    The lawn mower is a mobile, high-performance tool for beautifying home gardens and surrounding areas. With prolonged use, due to wear of parts or manufacturing defects, malfunctions occur, which lead to the trimmer stalling or not starting. Since this tool is a rather complex mechanism, there may be several reasons why the lawn mower stalls.

    Why does the trimmer stall

    There are two main ways to troubleshoot problems: transferring the braid to a specialized center or solving the issue with your own hands. The first option is suitable for those who are ready to pay a “tidy” sum to restore the unit’s working capacity, and the second one for those who have basic locksmith skills and can independently figure out the causes of breakdowns and ways to eliminate them.

    Currently, it is customary to classify breakdowns for which the lawn mower stalls into the following categories:

    • Mechanical damage to the internal combustion engine crankcase, malfunctions of the cylinder-piston group (CPG);
    • Breakdowns associated with the supply of the fuel mixture (air filter, carburetor);
    • Malfunctions due to damaged tubes, hoses, cables or ignition circuit.

    Lawn mower stalls at high engine speeds

    During operation, a situation arises when, when you press the fuel mixture supply button, the unit turns not increase, but decrease. A malfunction of this nature can be caused by:

    Fuel hoses for lawn mowers with filter

    • Etching atmospheric air into the combustion chamber;
    • Problems with the circulation of the fuel mixture;
    • Clogging of the breather in the fuel tank cap (cleaning the hole with a fine sewing needle);
    • Incorrect carburetor adjustment.

    When air is leaking during the operation of the internal combustion engine, it is necessary to check the tightness of the connection of the pipes and the integrity of the gaskets in the CPG. The problem with the circulation of the fuel mixture can be solved by removing blockages in the fuel pipes leading to the carburetor. If a vacuum occurs in the tank and the fuel mixture does not flow to the carburetor, it is enough to clean the breather with a thin needle and blow it with air.

    Petrol trimmer stalls at idle speed

    Often, when the engine speed decreases, the lawn mower engine stalls and does not idle when restarted. The main reasons for the occurrence of such a breakdown include contamination or misalignment of the carburetor, as well as clogging of the air filter.

    The petrol trimmer stalls when idling

    If the optimal settings of the carburetor are violated, it is necessary to clean it and re-adjust it. Clogged trimmer air filter can be dealt with by soaking it in a solution with common household detergent for several hours. If self-cleaning did not help to cope with the blockage, then it is better to purchase a new filter element in accordance with the instruction manual.

    After carrying out events, the user will not face a situation for a long time when the trimmer stalls at idle and functions only when gas is supplied.