What kind of problems are there?
All malfunctions can be divided into two large groups:
The following is characteristic of engine failure:
- The machine won’t start, it just stops;
- Does not pump fuel to the primer;
- Unstable operation, rpm floats;
- runs at idle, may float, throttle, fire when loaded.
If the problem is in other assemblies, such phenomena are noted:
When to call a workshop
If the machine is under warranty, at the first signs of incorrect operation it can be safely taken to a specialized workshop. Repair will be made free of charge, regardless of the nature of the damage, if it occurred through no fault of the owner. At breakage in the engine to the person who is not technically conversant, it is better to address at once to the expert. In any case, it is the user himself who decides on the severity of faults with his machine.
To sum up. Both gasoline and electric grass trimmers are designed for many years of reliable operation. Most of the problems described above occur due to the owner’s lack of attention to his helper. Provided regular maintenance and strict adherence to the manufacturer’s instructions are observed, the lawn mower will operate smoothly and accurately.
A neighbor asked me to tune up his chainsaw, his STIHL 180 doesn‘t rev up under load. I show you what was the reason
Do it yourself
My neighbor has a STIHL 180 chainsaw, and he brought it to me for adjustment. I worked all the time with a STIHL 361 chainsaw (semi-professional saw, as powerful as a tractor).
Basically the design of saws is identical, only with my neighbor’s Stihl everything is so tiny, it is not usual))
Started to figure out why the saw doesn‘t rev up on the run when you’re sawing a log. Saw is new, only two years old, carburetor is on factory settings, usually I don’t need to turn them at all. The spark plug worked, it was clean and the spark was good. Gasoline filter is clean.
All that remains is the air filter, which the neighbor has never cleaned. I, when I worked at getting firewood, every two or three days I serviced my chainsaw, washed the filter, carburetor.
Did the same thing with my neighbor’s saw. If you have not had a hand, not everyone will be able to carry out such a maintenance. That is why I made a special photo of each step. Maybe some of you might find this information useful.
How to rinse the air filter and carburetor on a STIHL 180 chain saw
Pull the throttle control lever of the carburetor down.
We can take off the protective plastic cover and see the air filter. The air intake tube is covered with a dirty deposit from a mixture of dust, sawdust and oil.
Lift the air filter, it is full of fine sawdust from underneath.
We clean the filter mechanically, then rinse it in clean gasoline.
Rinse it in a high bowl (a cut 5-liter plastic bottle will do). You put the filter in gasoline and move the bottle in a circular motion, creating a washing machine effect.
You can take out the clean filter (it is dark colored on the underside).
Now you have to wash the carburetor and all parts connected with it in the same way.
As we can see, the air inlet, though it is under the filter, is all dirty
To take it off, you unscrew two nuts which you can’t reach with a standard spanner. You need a small head and a ratchet.
Screwdriver with a small head. If you don’t have a screwdriver and a head, you will have to remove (loosen) the back plastic handle, which you can grip with your right hand. Then you can unscrew the nuts with a tube wrench 8 mm.
We took off the air intake, under it we see the carburetor, we put the air intake into a bottle with gasoline and rinse in the same way as we rinsed the filter.
Now it’s turn for carburetor, to remove it you need to disconnect throttle linkage. The long bent rod looks like a wire, goes from the handle, where the gas control lever.
Disconnect a short bent rod control the carburetor choke (it is on the left side).
Use a screwdriver to pry off the fuel hose from the carburettor.
Pod Poddevym with a screwdriver and take out of the socket plastic roller on which the lever toggles the positions of the air damper. Pull the other end of the plunger out of the hole on the right side.
Now we can pull the carburetor from the studs. Don’t twist it, don’t disassemble it, just put it in gasoline and rinse in a circular motion.
Next, remove the protective plastic casing, which is installed behind the carburetor and the same he rinsed in gasoline.
Clean the place where you installed the carburettor from dirt mechanically (a screwdriver and a rag are your help). Try not to let the dirt get inside the cylinder on the piston.
We are going to assemble everything in the reverse order, but be careful not to break anything!
We replace the plastic cover and press the latch with a screwdriver.
Put the fuel hose on the carburettor tube.
Insert plastic roller into the hole on the right side, throttle rod should be over the roller, not under it. In the picture below the rod under the roller, it is not correct (I had to remove the roller and put it under the rod again).
On the left side, you must first bend up the contact spring (you can bend the spring with a screwdriver) before you can snap the roller into the seat.
Hook the rod to the choke lever (this operation is difficult, you need to practice, be careful) and put its other end to the end hole of the roller).
Insert the contact on the wire in the socket on the roller.
Install the air intake on the studs and screw nuts. Tighten the nuts carefully so as not to overtighten the threads and at the same time strongly so that the carburetor is firmly pressed to the cylinder and does not suck the air.
After these actions it might take some time before the saw will start because the carburetor is leaking gasoline and the hose is leaking gasoline too. Yank the starter a few times and it will start.
Neighbor’s saw began to handle the load perfectly!
To avoid these problems, clean the air filter more often. But if you have to work a lot, you should still periodically flush the carburetor and all parts related to it.
This is a large and hard post to digest. If you’ve read this far, you might find it useful!
In my practice I had a case when the handwheel bumped the key in the Stihl 180 and the ignition went a little off. STIHL starts, runs at idle, but doesn‘t pull under load. It took me a long time to figure out what was wrong.
STIHL Fs 55 Grass Trimmer Doesn‘t Revolve
grass trimmer with gasoline drive. a useful thing for owners of homesteads, lawns, and when the grass trimmer suddenly stops, the work of clearing the area of grass stops. The device itself is a fairly complex mechanism, so there are many different causes of its failure. Please refer to the STIHL instruction manual for the most frequent problems. Knowing why a ride-on trimmer shuts down is the best way to ensure you get the most out of your machine.
Problems with the chain saw associated with the fact that this device does not start, are classified in a certain way by service specialists. They distinguish faults with the following assemblies of the mechanism:
- The engine, in which the piston and bearings may wear out or fail, the crankcase may crack;
- The fuel supply system, with possible clogging of the filter or problems with the carburetor;
- Mechanical damage to the wires, tubes, hoses;
- by the ignition circuit.
In order to correctly determine the node where the breakdown occurred, it is necessary to pay attention to the circumstances under which the grass trimmer stalls.
When the throttle is pressed
If the lawnmower stops when you press the gas, the causes may be.
- The most common variant is a failure of the carburetor adjustment, which occurs when there are significant loads on the drive, after prolonged inactivity of the mechanism or when it is used in harsh conditions.
- Fuel valve clogging, which can be eliminated by loosening it, as a result of which gasoline begins to flow through the system normally.
- Loose and hanging cable in the carburetor. Fuel hose can be also stretched up to the point of rupture, which is caused by significant load.
- A clogged breather valve (check valve), causing no fuel to enter the tank.
If the problem is related to the carburetor unit, you can recognize it by the appearance of vibration of the lawnmower. When the hose is burst or the cable is stretched. perform the replacement of these components.
At high engine speeds
When the grasshopper cuts out at high rpm, it is caused by the following problems:
- Fuel line tension or rupture caused by heavy load;. Clogging or sticking of the valve on the fuel filler flap;
- the carburettor is distorted by the vibrations produced by the machine
- problems with fuel mixture circulation;
- Atmospheric air drainage;
- the hose that is intended for fuel intake is cracked or poorly connected.
STIHL FS 55 lawn trimmer does not rev, stops, carburettor overhauled
STIHL FS 55 grass trimmer lawnmower Doesn‘t rev, shuts down, rebuild carburetor Thank you for watching.
The carburetor is adjusted, based on the operating instructions for the trimmer. Loosening the screws on the carburettor housing is often sufficient for a fine tuning. If there are problems with the circulation of the fuel mixture, the mixture may flow little by little into the carburetor. After it has worked out, the engine stops at high revolutions.
At idle speed
At idle speeds, common causes of the grass trimmer stopping are:
- reduced gearbox speed when the gearbox heats up, which is a consequence of using an unsuitable fuel mixture;
- clogging of the throttle valve;
Stihl FS46 String Trimmer won’t rev up
- Air is trapped in the system;
- insufficient fuel to operate the lawnmower.
If the problem area is the carburetor, the machine will stop both when cold and hot starting.
Immediately after starting the engine
The unit may stall immediately after starting, if the carburetor is unadjusted or has been improperly adjusted. this causes an uneven fuel supply. The result is that the unit begins to vibrate distinctly. To correct the problem, the carburetor is readjusted by acting on the instructions for the mechanism.
Also the engine will stop when the fuel valve is clogged. In such cases it is sufficient to simply clean it. If the lawnmower starts to run but then immediately stops, the fuel may be coming to the carburetor unit with some difficulty. Solve the problem by loosening the valve, which allows free circulation of the mixture in the system.
Stoking can also be caused by air leaks if the fuel intake hose is mechanically damaged (holes, cracks). In such a case, it is necessary to increase the engine speed to expel the air bubbles from the system more quickly.
The lawnmower often stops after heating up. It starts, works jerkily and stops gradually. This process occurs when the gasoline in the carburetor boils or the choke in it is installed rotary, not disc type. In the latter case, replace the part.
Grass trimmer sometimes gets warm if the ignition wire or coil is damaged. Parts must be replaced to keep the appliance running correctly.
When the air damper is opened
It happens that the unit shuts down when the air damper is opened, while idling normally. This is due to air suction by the system, caused by cracks in the fuel hose or problems with the seals. Also, the carburetor metering system can malfunction, and the lawnmower will stop after opening the choke.
All the possible reasons why the lawnmower stalls, and how to fix them are contained in the following video
Reasons for stopping a brushcutter are many, but the most common cause is carburetor malfunction. They can occur in any number of cases. The most problematic variant is when a serious damage occurs, and it is necessary to buy new parts or to change the lawnmower.