Stihl Trimmer Petrol Adjustment Carburetor

The STIHL FS 38 trimmer is probably well known to all fans of high-quality garden equipment. People who once tested the brand’s products in practice rarely switch to products of other brands, because German quality conquers completely and completely.

This lightweight gasoline appliance is quite compact, it is ideal for cleaning a small area of ​​household plots. Many owners of private sectors prefer this particular “assistant”, because he does an excellent job and demonstrates a high level of productivity.

0.9 liter two-stroke engine with. can withstand heavy loads, and the AutoCut mowing head can handle even relatively tall bushes and weeds. The D-shaped handle easily adapts to the growth of the operator, so the new owner will be able to adapt the unit completely for himself.

Since the engine displacement is 27.2 cm 3, the Stihl FS 38 trimmer can reach a fairly high speed. The presence of a special quick start system eliminates the need to run the unit several times in a row, because it will start working on the first try.

Specifications and Features

  • Cutting width: 23 cm;
  • Fuel capacity: 0.33 L;
  • Weight: 4.1 kg;
  • Bar: curved;
  • Fishing line thickness: 2 mm.

Thanks to the manual fuel pump, a person can easily pump fuel into the carburetor. This moment is especially important in that situation when the lawn-mower stood idle for a long time. Constantly adding fuel will allow you to quickly start the device even after a “long vacation”.

Together with the unit, the owner receives protection glasses and a mowing head. To understand the features of the assembly and other specific aspects of operation, it is possible thanks to the manual presented on our website.

Other useful information should be found in the following document:

The curved bar of STIHL FS 38 lawn mowers with a rounded handle deserves considerable attention. Thanks to this design, the device easily copes with cleaning the territory, even in a narrow or limited space.

All controls are placed on a convenient handle, so look for a long time, where and what switches is not necessary. During operation, such a moment is very important, because the operator can not be distracted and without unnecessary movements to regulate the operation of the machine.

Carburetor adjustment for lawn mowers Stihl FS 38

  • First you need to stop the engine;
  • Then install the mowing head;
  • The next step is to check the air filter, and if the filter element is in an improper condition, it should be replaced;
  • It is necessary to completely turn the idle adjustment bolt clockwise to the stop, and then 1.5 turns counterclockwise;
  • After starting the device, you should wait until the engine warms up;
  • Using the idle stop bolt, the owner must adjust the idle speed so as to immobilize the cutting tool.

It’s easy to deal with all the procedures, the main thing is to get serious and get ready for work. over, many owners note that you can independently carry out not only the carburetor adjustment, but also the replacement of spare parts. The schemes below will be excellent helpers in this matter.

Pros and cons of the model:

  • Great performance
  • Compactness;
  • Light weight;
  • Functionality;
  • Endurance;
  • The ability to independently adjust the operation of the elements;
  • The presence of a manual fuel pump;
  • D-shaped handle, etc.

Naturally, the list of positive aspects should include the verification of the brand itself.

  • The need to constantly check the fuel level;
  • A small motor resource;
  • Low power;
  • High cost;
  • Scanty equipment.

The presence of not particularly catastrophic shortcomings of the model does not adversely affect the popularity of the unit, because the ideal technique simply does not exist.

Stihl Fs 38 Trimmer Carburetor Adjustment

Annotation on the adjustment of the carburetor lawn mowers.

Carburetor adjustment and repair

The trimmer does not belong to complex household appliances, because most of its failures are mechanical in nature and can be successfully removed with their own hands. Even if the engine fails for severe reasons. damage to the piston ring, for example, repair is reduced to replacing the part.

And with a relatively conventional design, such a part of the device as a carburetor needs to be adjusted.

Principle of operation

Carburetor. a power system module in which liquid fuel and air are mixed before being fed into the engine cylinders. Gas mower adjustment carburetor. Depending on the tool and its operating mode, mixing and feeding are adjusted appropriately.

The carburetor device of the lawn mowing is monotonous for virtually all cases. Carburetor adjustment of Chinese lawn mowers. It belongs to the category of float devices. The latter provide constant characteristics of the finished consistency.

The mechanism of the module is as follows.

  • Air enters the body of the tube with an air damper. Lawnmower Matrix carburetor adjustment. The latter increases or decreases the air flow depending on its own position.
  • In the area where the hole for supplying gasoline is formed, the tube has a constriction. a diffuser. Here the flow rate increases.
  • Fuel from the float chamber through the nozzle is fed into the tube. The level of the float determines the amount of fuel supplied. Because the pressure in the chamber is normal, and the pressure in the tube is low due to the greater dilution of air, gasoline is sucked through the nozzle.
  • Accelerated airflow picks up fuel and atomizes it, forming an air-fuel mixture of suitable density.
  • The mixture is sucked into the cylinder through a pipe.

The stronger the air damper in the tube is open, the higher the density of the air flow, which means that more fuel enters the cylinder. Lawn mower stiga handle adjustment. Setting the carburetor of the lawn mowers is reduced to setting such a ratio of the dampers at which the density of the fuel consistency becomes good.

Signs of imbalance

Carburetor debugging is certainly done in the manufacture of the apparatus. Texas 330 Lawnmow carburetor adjustment. Usually, the owners will only find out about the need to adjust the fuel supply with their own hands after quite severe breakdowns, during the correction of which the module was removed and, for example, cleaned.

Signs of a failure in the settings are as follows:

  • it starts up, but the motor stalls here. since the engine can only work when a certain amount of gasoline is supplied, with very “poor” fuel, in other words, blocking the supply channel, the motor will stop;
  • very high fuel consumption, a lot of exhaust gases. the result of incomplete combustion of consistency. In this case, there is a lot of fuel, and the mixture comes out extremely dense.

See also

Trimmer Stihl FS 55 lawn mower Does not develop speed, stalls, sort out the carburetor

Stihl FS Trimmer 55 lawn mowing Does not develop revolutions, stalls, sorting out carburetor Thank you for watching.

STIHL FS 55. carburetor adjustment (idle)

Stihl FS trimmer carburetor adjustment 55 in the video we execute in order to adjust the idle speed.

The carburetor of the Stihl, Makita, Husqvarna and others lawn mowers is adjusted using the adjusting screws. Sometimes a prerequisite for the disorder of the work is a violation of fixation. due to vibration or damage to the protective cap. Such a breakdown can be found by simply trying to turn the screw a bit: if the fixation is not rigid, it is worth checking the setting.

Adjustment carburetor lawn mowers do it yourself

The configuration of the module does not apply to repair and replacement of spare parts is not required. In this case, the repair kit for the carburetor of the lawn mowers is not useful.

There are three screws for debugging:

  • L. is regulated first, because it is responsible for the supply of fuel at low speeds;
  • H. he is responsible for the supply of gasoline at high speeds, also for fuel consumption and temperature;
  • T. with its help, idle debugging is carried out.

There are options, usually a Chinese lawn mowing carburetor, when there is only one screw left for debugging on the case. for the idle option. Adjustment of valves on a lawn mower. This does not mean that the module is configured automatically. it means that even carrying out such a type of repair as debugging will be problematic. In the photo. carburetor adjustment of the Chinese lawn mowers.

  1. The module is configured only when the engine is warm: for this, the device has been turned on for 10 minutes before. Carb Adjustment Japanese trimmer. lawn mowing trimmer ignition adjustment. If the mowing head is spinning at idle, then proceed to debugging immediately: turn screw T counter-clockwise arrows until rotation is complete.
  2. The adjustment starts with screw L. The screw rotates to the right and to the left until it is found in such a position that the idle speed does not become the highest.
  3. Then the screw is turned ¼ turn counterclockwise. This will be his working position.
  4. Idling must be adjusted by turning counterclockwise to increase the speed and clockwise to decrease. Its debugging consists in achieving such a mode in which a sufficient number of revolutions is made before the mowing head rotates. Lawn mowers gasoline self propelled speed adjustment. With all this, the engine should work stably at various positions.
  5. The position of the screw L is determined last. at maximum speeds the trimmer should not work for more than 10 seconds. The throttle opens, the screw rotates clockwise, very slowly, until a decrease in the number of revolutions is established by ear.
  6. Then, also, the screw rotates slowly counterclockwise until the motor starts to malfunction. After that, the screw is turned back clockwise until the engine again works normally.

If there is a tanometer, and if the recommended revolutions are indicated in the product passport, the correction can be made more accurate, focusing not on the ear, but on the readings of the device.

6 post comments &Carburetor adjustment and repair&

Please clarify. In the adjustment section of clause 5, screw L error? Should I read screw A? Thank you

tell me the initial position of the screws H L LA

TIP INITIAL POSITION

tell me the initial position of the screws H L LA

Lawnmower Stihl FS 38. problems and solutions

Good morning. Please help me deal with the fs 38 trimmer. I got it not working, namely, the drive shaft does not twist the shank. When disassembling. in the tube there are 2 bushings and a drive shaft, from above the shank was fixed with a bolt through the tube. I read here about some circlip. I understand that when you press the gas, the drive shaft flies out and does not twist the shank, help me figure it out

Video: Stihl Trimmer Petrol Adjustment Carburetor


MStihl wrote:
BigMazzy, 0.1-0.3mm gap from flywheel magnets

Kain81 wrote:
Good morning. Please help me deal with the fs 38 trimmer. I got it not working, namely, the drive shaft does not twist the shank. When disassembling. in the tube there are 2 bushings and a drive shaft, from above the shank was fixed with a bolt through the tube. I read here about some circlip. I understand that when you press the gas, the drive shaft flies out and does not twist the shank, help me figure it out

All figured out. The upper part of the pipe was bent and not fully inserted and was not clamped with a screw. Therefore, the drive shaft poured

Good morning!
Connoisseurs, tell me what the problem is: gas stopped flowing into the so-called “nipple” on the carburetor. Pressing leads to nothing. The fuel filter is new, when you remove the upper part of the carburetor and press the spring, the gas goes. And most importantly: they climbed into the carburetor, t.k trimmer worked only at idle, as soon as you press on the gas stall immediately.

Dear forum users! Help with the repair, please! I will start in order: I gave a trimmer to a neighbor for a day to mow the grass on the lawn. There was a full tank of gasoline. (He has his own gas) After about 40 minutes he says: “I’m working at idle, but you let the gas stall”. It turned out that he poured a mixture in which there was 2 times more oil than needed. (Instead of 100ml-200ml). But it turned out later, and before that he climbed the carburetor, dismantled it, screwed something up and now gasoline it doesn’t get into the nipple on the carburetor at all. Knowing people help, otherwise it’s far to go to the service, and it’s unreasonably expensive there.

scham wrote:
he climbed the carburetor, disassembled it, twisted something, and now gasoline does not enter the nipple on the carburetor at all.

I have not 38th. But trying to guess. I don’t know if the 38th filter is in the tank, then the hose, Well, I don’t know the carb itself, I didn’t climb.

the filter in the fuel tank is new.

scham, see the hose. Not pinched, or vice versa not damaged, maybe the air sucks. Then it will not upload either. If everything is fine, I’ll try to contact a specialist at the expense of a carb.

valerich, thanks! The hose is probably okay too, because if you remove the nipple and the gas pump, then the gas goes. It seems to me that when he dismantled the carburetor, it could damage the gasket (there is a slight bend).

valerich wrote:
I will try to contact a specialist at the expense of a carb.

Already addressed. I think he will unsubscribe.

scham wrote:
he climbed the carburetor, disassembled it, twisted something

Go, torture him, what exactly did you do with the carburetor. did you take it off, what covers did you open (if you opened)
Which of the screws twisted and how much.
So, without this information, nothing can be said at all.

Yes, and be sure to check the exhaust pipe on the muffler. if it is clogged with soot.

Anyway. give the braid to a neighbor and let him play in the service. In the end, what a habit of taking other people’s things and poking around in them. I took it, it didn’t work as it should. give it back and say that it does not work.
In short, okay, give information, we will think. I will not croak for now, maybe everything will work out.
I’ll drop in periodically, although I’m sitting on a very frail Internet.

Olegych wrote:
Anyway. give the braid to a neighbor and let him play in the service. In the end, what a habit of taking other people’s things and poking around in them.

Stopudovo agree. Climb? Now let him take and repair to the state in which he took.

Olegych wrote:
Anyway. give the braid to a neighbor and let him play in the service. In the end, what a habit of taking other people’s things and poking around in them

Yes, I would have done so, but a person has helped many times in different situations, and so it will not be very beautiful on my part.
He says that he removed the upper part, where the nipple, pump, gasket and membrane. He twisted the fuel supply screw, but then set it as it was.

Well, have any ideas?

I could confuse the membrane with the gasket in places.
Remove the top cover, arrange the parts in order, take pictures. we will see.

Olegych Already checked, first the gasket, then the membrane.
I think that it makes sense only to photograph the gasket, because there is a small room on it.

scham wrote:
Already checked, first the gasket, then the membrane.
I think that it makes sense only to photograph the gasket, because there is a small room on it.

It’s all about the pump piston, it’s in the carburetor. You need to remove the throttle, carefully! The piston will fly out, remove the spring. You will grease the piston with an autolock, and you will not completely plant it, so that the piston does not interfere with the throttle shaft. plant deep, close the channels.

I’m sorry that no one could help you)) I am on the forum for the first time)))

scham, if you have questions about the carburetor assembly order or adjustment, write! I will answer)))

scham wrote:
It turned out that he poured a mixture in which there was 2 times more oil than needed

this is not a problem, the problem may still be in the quality of the fuel itself. What kind of gasoline, oil? How many days is it already active (how many days have elapsed from fuel preparation)? People, always pour fresh fuel! When oil enters gasoline, a chemical reaction occurs (decomposition of oil in gasoline) and, due to external factors, the survivability of the fuel depends.

scham, damn it) check the muffler before that. Maybe he is clogged?
” >. if that knock!

Uncle Syoma °, tell me what should be the gap between the roter and the stater?

Post number 126
. “It works at idle, but how you give gas it stalls.”

The fuel is fresh, only from the column. The oil is right and 1:50. The muffler is dry and clean. Launch with 1-2 attempts.

Multik_off wrote:
It’s all about the pump piston, it’s in the carburetor. You need to remove the throttle, carefully! The piston will fly out, remove the spring. You will grease the piston with an autolock, and you will not completely plant it, so that the piston does not interfere with the throttle shaft. plant deep, close the channels.

Stihl Trimmer Petrol Adjustment Carburetor

Thanks for the hint. how to fix the malfunction, but. where and how is this piston, throttle, etc.

T.O. questions have ripened:

  1. Where can I get acquainted with the theory of this carb? Description, the principle of operation of its systems.
  2. Where to get hold of the explosion-diagram of this carba (well, at least similar)?
  3. Possible malfunctions and solutions?

I would be very grateful for any information: literature, links, videos, etc.

I’ll share the diagrams, but I don’t know how to “stuff stuff into caramel”

Old Man-L wrote:
Where can I get acquainted with the theory of this carb? Description, the principle of operation of its systems.

As far as I know. On such a technique carburetors such as walbro (or ZAMA, of the same type) are used. There are plenty of schemes and descriptions of walbro on the internet.

He took a steam bath with this question from work from that-oh-oh-about-some Internet. it was painfully unbearable: the engine did not work, the infection!
I came home. a large “coffin” with a “thick” cable quickly gave out a lot of useful information.
Sinus, valerich. thanks for the help!
Now I’ll dig in more detail, but if there are questions, I’ll be back!
=
It is like a conversation of two or more people in any language (in this case, in technical): communication is possible only if you know the language! So. I will teach.

Old Man-L wrote:
there will be questions. I’ll be back!

Lawnmow Stihl FS38. Description of the model. Features of operation, maintenance

Overview

The Stihl FS38 lawn mower belongs to the light group and is the optimal complement to a powerful lawn mower for decorating hard-to-reach areas along paths, under trees and bushes. Using the STIHL mobile lawn mowers, you can quickly cut soft, overgrown grass on lawns and lawns, always keep a small area in a neat condition.

Technical specifications Stihl FS38

  • Model. FS 38 Autocut.
  • Weight. 4.1 kg (without cutting equipment).
  • Lawn mowing length. 147 cm (without cutting equipment).
  • Engine type. two stroke.
  • The volume of the cylinder is 27.2 cubic meters. cm.
  • Power. 0.9 HP
  • Type of fuel. gasoline.
  • Gasoline consumption. 0.32l / hour.
  • The volume of the fuel tank is 0.33 liters.
  • Handle. a circular handle.
  • Cutting diameter. 380 mm.
  • The largest number of revolutions of the working head is 9500 rpm.
  • Anti-vibration system. installed.
  • Easy start system. installed.
  • Cutting tools. AutoCut C 5-2 head (included).

Model description

The Stihl FS38 Lawnmower is the lightest mobile version with 0.9 horsepower and is designed for domestic use.

  • Thanks to a modern electronic ignition system, a reliable start and uninterrupted operation of the engine is ensured.
  • Using a fuel pump, the operator can, if necessary, pump fuel into the carburetor.
  • Optimum maneuverability is ensured thanks to the D-shaped handle, with which it is convenient to control the Stihl lawn mowing when working in difficult areas.
  • All control levers are located on a special multi-function handle (R), which ensures the safety and reliability of the gas trimmer.
  • Thanks to the AutoCut C5-2 mowing headset, the mowing diameter is 380 mm.
  • The ergonomic shoulder strap allows you to hold the Stihl Lawnmower on the shoulder, rationally coordinate movement during operation.
  • Light weight (4.1 kg.), Small dimensions, rational basic equipment. thanks to these characteristics, STIHL 38 lawn mowers are extremely comfortable to use.

Operational Features

Each Stihl lawn mower is designed strictly for the intended work, taking into account engine power. The manufacturer categorically does not recommend retrofitting or improving the braid device on its own. Therefore, before buying a STIHL lawn mower, you must clearly determine the upcoming work front.

It is completely inadvisable to acquire a powerful trimmer for periodically mowing grass on the lawn; for this, light gasoline or electric models of mowers are quite enough.

During operation it is important:

  • Observe the mode: work / rest at intervals of 20 minutes.
  • Use high-quality gasoline not lower than AI-92.
  • To prepare the fuel mixture, use original STIHL engine oil (50: 1).
  • When the engine is run-in to 2-3 full refueling of the fuel tank, do not allow operation at maximum load.
  • When preserving the braids for the winter period or the expected interruption in operation, in order to avoid engine damage, it is imperative to drain the remaining gasoline from the fuel tank.
  • To ensure stable operation, systematically check the condition of the fuel filter. clean or replace with a new one.
  • To prevent serious malfunctions, clogging of the air filter must be avoided.
  • Fulfill safety requirements during operation of STIHL lawn mowers.

Strict adherence to the operating instructions is the key to the long and trouble-free operation of the Stihl lawn mowers.

Instructions for use lawn mowers STIHL FS38

Advantages and disadvantages of the model

For mechanization of mowing grass in a small area of ​​the lawn mower, the Stihl FS38 is perfectly suited. The cleanliness and accuracy of the cut, mobility, lightness and high performance are huge advantages compared to a manual scythe.

Owing to malfunctions, owners often note that immediately after starting the STIHL, the STIHL can simply stall. In this case, check the fuel channel for clogging. Another reason may lie in the incorrect adjustment of the carburetor, which is easily eliminated in accordance with the recommendations for service.

The price of Stihl FS38 lawn mowers is about 9 thousand rubles. Of course, on the market you can buy cheaper, often short-lived counterparts.

A well-known brand guarantees the reliability of certified products, as noted by the owners of the equipment.

Video review of work

Maintenance and repair of the Stihl FS38 lawn mower

lawn mowing (Trimmer) Stihl FS38

lawnmower Stihl FS38 common “sore”

Owner reviews

Andrew:

“I bought the Stihl FS38 lawn mower for permanent mowing of grass in the territory of about 10 acres. Over 7 years of work, I felt how much easier it is to maintain the site with such equipment. The engine is quite economical, of course, its capacity is not enough to clear the bushes. Comfortable shoulder strap, work comfortably. ”

STIHL FS 38

gasoline, 650 W, equipment: fishing line, weight 4.1 kg

295.00 p. from 7 sellers

11 years on the site
user # 95978

who knows whether it is possible to put a knife on this trimmer?

11 years on the site
user # 70457

No, he’s weak for a knife.

11 years on the site
user # 95978

6 years on the site
user # 617577

A “head” with 3 inertial plastic knives is placed on this trimmer. a very good alternative to metal knives. take my word for it.

8 years on the site
user # 227236

how to adjust this lawn mowing, it works at idle, stalls under load, you can squint a little. Only occasionally pressing the gas, but the right hand gets very tired from this “jerking off”, it’s easier to knock down the tops with an ordinary scythe.

5 years on the site
user # 684876

fedorov.stepan, what kind of head, discard the photo in PM. New prices fs 38 cm http://airtehno.by/STIHL/kustorezyi-i-motokosyi/

8 years on the site
user # 245476

how to adjust this lawn mowing, it works at idle, stalls under load, you can squint a little. Only occasionally pressing the gas, but the right hand gets very tired from this “jerking off”, it’s easier to knock down the tops with an ordinary scythe.

This is most likely a carb problem. How much is your trimmer? If the new one is in guarantee, if the old man, then there is another option that the seals are covered, but this is a very rare case. There are also two common diseases. Over the years, either a silencer or an exhaust window of a cylinder is clogged, and the sound of the engine is usually determined by an experienced craftsman when starting the engine. And the second disease in recent years is the ignition coils on the fs38 and fs55, everything is the same there. Also check the fuel hoses for cracks (I haven’t seen anything like this on these trimmers yet.). I do not advise regulating the screw marked with the letter L, and H, too. The first is the adjustment at low speeds, the second is from the factory with a plastic limiter, it is responsible for the maximum speed. If the braid worked fine, then there were problems, then first you need to rinse the carburetor, then watch the adjustments, the adjustments themselves do not go astray, and you can’t remove the dirt from the carburetor by adjusting. It happens that people will adjust so that the sound works fine, but then they repair the motor. In trimmers and chainsaws, in addition to cooling the air outside the engine with the edges of the cylinder, there is also the concept of internal cooling due to the evaporation of fuel, and if it is not enough for this, then you will kill the engine in half an hour. This happens when air is sucked in through seals or other possible places or when the carburetor is not correctly adjusted (screw L). The maximum revolutions are set on the electronic tachometer and on the trimmers no more than 10,000. You can find out how many maximum revolutions and standard adjustments are possible from the original instruction manual for your instrument.