How To Adjust The Lawn Mower

Carburetor adjustment

This aspect is always needed when setting up lawn mowers. A properly tuned carburetor is the key to successful lawn mower engines.

Despite the fact that the question of how to adjust the carburetor on a lawn mower seems incomprehensible to beginners, but the repair of lawn mowers often ends with this procedure, since the reasons lie in incorrect adjustment, and the repair of lawn mowers and how to eliminate them in the adjustment procedures. By the way, running in lawn mowers also provides for the adjustment of the carburetor part.

To understand how to properly set up a gasoline carburetor for lawn mowers, you need to know:

  1. The device contains three screws: right (L), bottom (T), left (H).
  2. A properly tuned carburetor idles evenly and without fluctuations when the engine is cold and hot, as well as during a sharp descent or acceleration. The screw T is responsible for idling.
  3. The L screw is responsible for how much fuel mixture will enter the combustion chamber at low rpm. When adjusting, the screw turns counterclockwise a quarter of a turn.
  4. The fuel is adjusted at high revs by means of screw H. To adjust, give full throttle by opening the throttle. Turn the screw clockwise until you hear a drop in RPM. Then, turn the screw in the opposite direction so that the engine runs unevenly, then start slowly turning the screw clockwise again until you begin to hear smooth and smooth operation of the motor.
How To Adjust The Lawn Mower

Cleaning the mower blades

The correctness of the adjustment is determined even by the color of the working part of the candle. If the carburetor setting is made correctly, then the candle will be clean, without carbon deposits.

For a 2-stroke unit, 2-stroke engine oil must be used. To the menu

The last left screw is adjusted as follows:

  • The throttle valve opens completely and full throttle is squeezed out;
  • The screw rotates clockwise until the revolutions decrease (orientation by ear);
  • We turn the screw counterclockwise until the engine operation becomes uneven intermittent;
  • We turn the screw to the position in which it ensured stable and smooth engine operation.

Do-it-yourself lawn mowers carburetor adjustment. Trimmer carburetor

The modern gasoline trimmer is a complex unit that includes a carburetor. It is on its reliable and correct operation that work performance will depend. Carburettor trim adjustments should be made in the following cases:

  • After running in the engine (as a rule, this requires 4-5 liters of gasoline);
  • Before the start of the mowing season;
  • If during operation due to vibration the adjusting screws are loosely unscrewed.
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Taking into account the fact that the trimmer does not belong to the category of complex units, you can adjust the carburetor yourself.

Similar entries. It is considered correct to adjust the idle speed when:

1.Cold engine idling steadily; 2. A hot engine does not idle too high; 3. There is sufficient speed reserve before the trimmer head starts rotating; 4.The engine runs stably in any position (for example, when the knife is lowered sharply).

Note: From the factory (Husqvarna) the idle screw from fully tightened was unscrewed by 8 full revolutions and 2 hours (now it remains). Recommended idle speed for Husqvarna lawn mowers 2.900 rpm.

3) The left screw H adjusts the enrichment of the high-speed mixture (adjustable last). It regulates maximum RPM, engine power, temperature and fuel consumption.

Note: The Husqvarna engine must not run at full speed for more than 10 seconds.!

Open the throttle fully (full throttle) and slowly turn the left screw clockwise until the Husqvarna engine is reduced (audibly). Then turn the left screw very slowly counterclockwise until the engine runs roughly. Then turn the screw back a small amount clockwise slowly until the engine for Husqvarna lawn mowers runs smoothly.

This completes the carburetor adjustment of the lawn mowers.

Note: Recommended maximum Husqvarna engine speed is 11.500 rpm. The maximum engine power output of the Husqvarna 333R lawnmower is 1.6 kW (2.1 HP) at 8,400 rpm.

Note: On a new Husqvarna lawn mower from the factory (Husqvarna), the left screw was completely unscrewed (0.5 turn) and blocked (covered) with hard plastic, which I drilled out at the end of the warranty period. Now the left screw (like the right one) is looking at approximately 11 o’clock.

Auto Privat

First stage

The adjusting screws for the highest and lowest speed should be moved clockwise until the highest resistance is encountered. When the screws reach the stop, you need to move them in the opposite direction and leave them after 1.5 turns.

Functions and working principle

In order to understand how the lawn mowers carburetor works, you should get acquainted with its operating principles. The main elements of the carburetor are the throttle valve, the function of which is to control the air supply. The operation of a device such as a carburetor can be considered in stages.

  • Air mixture supply to the compartment where the throttle valve is located.
  • Moving air flow assists in moving and atomizing fuel through the jet.
  • The resulting mixture (air fuel) is fed into the engine cylinder.
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Having become acquainted with these main stages, we can conclude: the more the throttle valve is open, the more gasoline consumption during the mowing process.

Instruction for Chinese

To properly configure the carburetor of a Chinese chainsaw, you must first remember the factory settings of the device, then turn on the engine. Subsequently, you will have to leave it to work for several hours in order to accurately set your own parameters. Sometimes work is performed once after a ten-minute operation of the engine, however, many Chinese-made models require special handling.

Chinese Chainsaw Model

Adjustment procedure:

  1. Activities start in idle mode. With the help of the adjusting screws, you need to achieve a systematic set of revolutions by the engine, so you should first let it run at low speeds. The deviation from the norm is the movement of the chain along the tire. In this case, you need to adjust the extreme screws to the optimal position so that the chain remains stationary.
  2. Transition to average speed is in progress. Sometimes the engine will smoke. This defect can be eliminated by tightening the screw to supply a leaner fuel mixture.

In this case, the smoke will disappear, but the engine speed will increase. It is necessary to adjust the settings until the level is reached when, when pressing the throttle, the engine smoothly picks up speed, no sudden jerks or interruptions are heard.

  • Device motor is being checked. The chainsaw is moved to minimum speed, and then the lever is rapidly pressed. At maximum pressure, it is held for 3 seconds. If there is a malfunction of the engine, gradually loosen the screw until the optimal position is reached.
  • The chainsaw should run for several hours under real conditions. It is necessary to engage in sawing wood, and then inspect all the elements involved in this event. If there are deviations, they must be corrected using adjusting devices. When all defects have been eliminated and the optimal settings have been established for supplying correctly concentrated fuel, the process of setting up the device can be considered complete.

    Take a look at:

    About the carburetor device

    The carburetor serves to mix the combustible consistency with air, observing the proportions established in advance. If clear doses are not followed, the serviceability of the motor is at risk. When a huge amount of air enters during mixing of a component, and there is not enough fuel, then this mixture is considered poor.

    Over-saturation should not be allowed, because with a large amount of fuel compared to air, malfunctions or engine wear are also likely. Adjustment of the carburetor is needed not only before the initial introduction, but also when any differences in its operation are revealed. Before using the chainsaw, do not forget to run it in.

    Components of the carburetor

    The carburetor design contains a standard set of parts, but may vary little depending on the manufacturer. Components:

    1. The basis. It is a special tube that visually resembles an aerodynamic structure. Air passes through it. In the transverse direction, a damper is located in the middle of the pipe. Its position can be changed. How to adjust the carburetor on How to change the piston on the trimmer. The more it is pushed into the passage, the less air enters the engine.
    2. Diffuser. This is the tapered part of the tube. Here’s what it looks like on how to adjust the carburetor on a chainsaw to tune. With its help, the air flow rate increases exactly in the segment from which the fuel comes out.
    3. Channels for fuel supply. The fuel mixture is contained in the float chamber, then passes into the nozzle, from which it flows into the sprayer.
    4. Float chamber. It is a separate structural element, reminiscent of the shape of a tank. Designed to constantly maintain an optimal level of fuel fluid in front of the entrance to the channel where the air comes from.
    5. Not sure which chainsaw to choose? Read our article.

      Looking for models that are cheaper, but reliable and time-tested? Pay attention to Russian-made chainsaws.

      Alternatively, research foreign chainsaw manufacturers such as Stihl.

      How to adjust the carburetor on a lawn mower

      My first channel: Free consultation.

      In idle mode, the engine may stall (the reason is here). In this case, immediately turn the adjusting screw clockwise until it stops. Sometimes the chain starts to move. In this case, turn the adjusting screw in the opposite direction.

      The last left screw is adjusted as follows:

    • The throttle valve opens completely and full throttle is squeezed out;
    • The screw rotates clockwise until the revolutions decrease (orientation by ear);
    • We turn the screw counterclockwise until the engine operation becomes uneven intermittent;
    • We turn the screw to the position in which it ensured stable and smooth engine operation.