An indispensable tool for a modern summer resident or owner of a private house is a petrol cutter, which allows you to effectively and efficiently put the adjacent territory in order. The period of active use of brushcutters is in late spring until October. Modern units are equipped with powerful and durable internal combustion engines, reinforced transmission and main components. Despite this, physical wear, manufacturing defects or improper operation lead to failure of the trimmer. In order to repair the trimmer with your own hands, you must have at least basic knowledge in the field of technology and little experience in repairing it.
The main unit of any gasoline tool is the internal combustion engine (ICE), which, through various methods, transmits torque to the actuator. In a modern petrol cutter, a duralumin rod (pipe) is used as a transmission element between the engine and the trimmer head, inside which the drive shaft is located.
Thanks to the high-revving engine, the line speed can reach 13 thousand revolutions per minute, depending on the manufacturer of the scythe. In order to exclude mechanical and thermal damage to the gearbox, a special hole is provided in its housing for the introduction of grease in the form of ointments. To make the headset easier for the owner during long-term work, all brushcutter models are equipped with a durable shoulder strap.
Regardless of the manufacturer, almost every model comes with a line and steel knives.
The cross-section of PVC trimmer line can vary from 1.5mm to 3.0mm.
Made of durable polymer, it is subject to intense wear and tear during mowing. Therefore, from time to time it is necessary to check the presence of a fishing line in the head and, if necessary, replace it. It is recommended that you purchase an extra bobbin to quickly replace it with a spool with no line.
ICE trimmers on the market today are equipped with a D-shaped, U-shaped or T-shaped handle, where the main controls of the unit are located. For example, in a braid with a U-grip, the throttle key and stop / start toggle switch are located on the right grip. In the D-shaped version of the handle, the throttle control button is located directly on the rod.
Due to the presence of many components and parts, repairing a trimmer with your own hands means eliminating breakdowns that prevent its normal operation. It should be noted the most basic malfunctions of gasoline streamers:
The main unit of any internal combustion engine is a cylinder-piston group (CPG), which can fail due to wear of parts of parts or poor quality of the fuel mixture.
Lubrication of rubbing units in a petrol cutter is carried out by adding a certain proportion of oil to gasoline. This process can be disrupted due to old oil precipitating out.In this situation, when the trimmer is started, the motor overheats and in a matter of minutes the most expensive breakdown occurs. To eliminate the malfunction that has arisen, a complete replacement of the CPG will be required, namely: the piston, oil seals, cylinder and piston rings. If you are not an ICE repair technician and do not have experience working with technicians, then you will hardly be able to fix the engine without the help of a specialist. Details on the stages of piston trimmer repair can be found here.
If the ignition of the petrol mowers fails, the spark on the candle disappears and, as a result, the fuel mixture does not ignite.
In this situation, it is quite important not to rush to replace the coil, since the cause of the breakdown may lie in the lack of contact in the switch on the control handle.
An important point when troubleshooting the trimmer ignition will be the section diagnostics, where the distance between the side and center electrodes should be 0.5-0.7 mm. In addition, it is necessary to pay attention to the steel O-ring on the spark plug, the loss of integrity or deformation of which can lead to etching of air from the combustion chamber and, as a result, reduce the power of the streamer.
If the replacement of the check of the electrical circuit, the spark plug and its contacts did not give positive results, then you should pay attention to the trimmer ignition module, namely the clearance with the flywheel. Regardless of the design features and the manufacturer of the brushcutter, the distance between the ignition coil and the flywheel should be no more and no less than 0.2 mm. To restore the optimal value of the gap, you will need to loosen the coil mounting bolts and set the trimmer ignition with a special measuring probe.
A clear sign of a malfunction of the engine power system is the absence of traces of the fuel mixture on the spark plug electrodes, which may be associated with the following defects:
You can quickly determine the cause of the malfunction by dismantling the fuel hose leading to the carburetor. If the fuel mixture flows out in a thin stream, then you should pay attention to the carburetor. If there is no jet, it is necessary to clean the breather with a thin needle (a small hole in the gas tank cap) or replace the fuel filter.
If fuel enters the carburetor, it must be cleaned or adjusted. Adjusting the carburetor trimmer means restoring optimal fuel mix.
To do this, pay attention to three adjusting screws: maximum speed (H), minimum (L) and idle speed (LA). To start the adjustment, you need to fully tighten the screws H and L and loosen one turn each. Then we start the braid and let it warm up for 10 minutes to adjust the power system in operating mode. After warming up the internal combustion engine, press the gas supply button until it stops (12,000 rpm). We restore the idling mode by unscrewing the screw LA. As soon as the trimmer head starts rotating, tighten the screw until it stops.
One of the common faults of the petrol mowers is the incorrect operation of the internal combustion engine, namely the drop in power with increasing speed (the scythe stalls).
The reason for this is that the exhaust system is clogged with burnt oil particles. Often manufacturers make mufflers prefabricated and cleaning is quite simple.If the design of the spark arrester is non-separable, then it must be placed in water with detergents, and then dried with an ordinary or industrial hair dryer. Frequent clogging of the exhaust system indicates non-observance of the proportions of oil and gasoline.
Very often, complaints from owners of gasoline trimmers are associated with various kinds of carburetor malfunctions. Of course, in this case, it is best to seek help from specialists in this field, for whom the repair of carburetors of gasoline trimmers is an integral part of the profession. However, if you are still familiar with the basic principles of the trimmer carburetor, you can try to figure out the problem yourself, so as not to overpay money in the service, since sometimes the breakdown can be really frivolous.
This article is just intended to help you deal with the problem.
Next, we will analyze the most common breakdowns and the reasons for their occurrence.
The first step is to generally inspect the carburetor and find out if there is any fuel leakage.
If it turns out that there are no problems with fuel, it is necessary to remove the carburetor from the engine and check the condition of the gasket located next to the carburetor.
If no malfunctions are observed here, you can try to check the carburetor for tightness.
To do this, you can purchase a special device, which is part of the tool kits for repairing the carburetor repair of mowers and representing a special pressure gauge that, in fact, checks the tightness.
If you don't want to spend money on its purchase, you can use a conventional medical tonometer, on which you just need to change the pressure gauge.
When using this device, pay attention to the indication.
If the pressure does not drop and remains the same for a long time, you can rest assured, as this indicates the tightness of the carburetor.
If the pressure begins to decrease after a certain time, then there are still problems.
They can be associated with damage to any parts of the carburetor.
Before running to the nearest repair shop or specialty store selling trimers and spare parts, try to figure out the problem yourself. Sorry for the banality, but the brushcutter carburetor is not a spaceship of an extraterrestrial civilization, and it is quite possible to repair it with your own hands. To be confident in your actions, read the step-by-step instructions provided in this article.