Adjustment Of The Carburetor Of The gas trimmer

Carburetor Adjustment Lawn Mowers Highlights
Do-it-yourself lawn mowers carburetor setting. Adjustment of minimum, maximum speed, idle. Tips for maintaining the carburetor trimmer.

Carburetor Trimmer Adjustment

The initial step in restoring the correct operation of the fuel system is to clean the air filter.

Trimmer carburetor with screws

Experts recommend rinsing it in a solution of water and detergents after every 10-15 hours. Direct adjustment of the carburetor trimmer is done with three adjusting screws:

  • Fuel adjustment screw (“L”);
  • High speed adjustment screw (“H”);
  • The screw responsible for the engine idling (“T” or “AT”).

Adjusting the idle trimmer

Location of carburetor adjustment screws

The “T” (“AT”) screw serves as a limiter for the reciprocating movement of the fuel flap and when it is tightened, the engine speed increases, and loosening leads to a decrease in the crankshaft speed. Professionals advise adjusting the idle screw of lawn mowers so that the internal combustion engine runs a little faster at minimum speed, but the head with a fishing line or knife remains stationary. If after the performed manipulations it is difficult to start the trimmer “cold”, then it is enough to tighten the screw “T” a quarter of a turn and try to start the engine again.

Adjusting the maximum speed screw for lawn mowers

After restoring the fuel supply at minimum speed and adjusting the idle speed, it is necessary to check the stability of the mechanism at an increased speed.

Tuning at maximum speed

The motor is adjusted at high speeds in order to protect against overheating and to reduce hand fatigue when pressing the accelerator button. If the internal combustion engine is unstable at maximum speed, then the screw “H” must be tightened slowly until smooth and precise operation is ensured.

During the operation of the lawn mower it may be necessary to readjust the fuel screw (“L”) for optimal speed gain.

Lawn mower or trimmer

A trimmer is a broader concept than a lawn mower (lawn mower), as it can also be electric. A petrol trimmer and a lawn mower are one and the same.

Some authors claim that the trimmer is a weaker tool than a more powerful lawn mower, which can be used for mowing shrubs. Personally, I have a tool with a maximum power of 1.7 kW and is capable, as stated in the instructions, of mowing small shrubs up to 10 mm thick. The user’s manual is called “Petrol trimmer.”.

Fuel supply adjustment

Begin to slowly tighten the fuel mixture adjustment screw until the engine starts to stall or stalls if you do not have time to catch the moment. After that, unscrew the screw a quarter of a turn if the engine has not stalled, or half a turn if it stalled. Start the stalled engine. Check by opening the throttle as the engine picks up speed. Continue to unscrew the screw No. 1 by a quarter of a turn until the engine starts to accelerate steadily during gas circulation. This will be the moment of the most economical stable engine operation. For the PRORAB-8406 petrol trimmer, the adjusting screws are turned clockwise, unscrewed. Counterclockwise, for some other brands of lawn mowers it may be the other way around.

Maximum speed limitation

After adjusting the fuel mixture and low speed, check how the lawn mower engine will run at maximum speed. If necessary, limit the maximum RPM to the required level with the # 3 hollow screw. Loosen the retaining nut and turn in the screw to decrease the maximum RPM or turn it out to increase it. Tighten the nut after adjustment. The maximum RPM setting is necessary to protect the trimmer motor from overheating and to be able to use the key release to reduce right hand fatigue.

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In the future, it may be necessary to adjust the trimmer carburetor. For example, if the engine starts to rev poorly when running at full load, loosen screw # 1 another quarter turn. If starting is difficult, increase idle speed. Both weather conditions and the quality of the fuel mixture can affect the operation of lawn mowers. Vibration can cause the adjusting screws themselves to turn.

Step by step instructions for disassembly

The carburetor device of models of different brands is almost the same, so take the Partner chainsaw as an example. We carefully remove each element and put it in order to make it easier to assemble later.

Chainsaw carburetors from different manufacturers, if they differ, it does not matter

The top cover is removed by unscrewing three screws. Following it is foam rubber, an integral part of the air filter.

The arrows indicate the bolts that must be unscrewed to remove the cover

Then we remove the fuel hose, followed by the drive rod.

The upper arrow points to the fuel hose, the lower arrow to the drive rod

Next, remove the tip of the cable.

The arrow shows the end of the cable to be removed.

On the left from the fitting, we pull together the gasoline hose.

We also carefully remove the gasoline hose indicated by the arrow

We finally disconnect the carburetor, it is ready for adjustment. Its mechanism is rather complicated, therefore, if further disassembly of the carburetor is required, the elements should be removed very carefully. They are small, so they can be lost.

The carburetor consists of many small parts, which should be laid out in order during disassembly.

When is adjustment necessary at all?

Specifically, adjusting the carburetor of a chainsaw is required in rare cases, more often there are problems associated with the flow of fuel or wear of parts. But sometimes “symptoms” indicate that it is necessary to adjust the mechanism. Here are some signs:

  • After the engine starts, it immediately stalls. Alternatively, it won’t start at all. The reason lies in the excess air and fuel shortage.
  • Increased fuel consumption and, as a result, a large amount of exhaust gases. This is due to the reverse process. Oversaturation of the mixture with fuel.

The reasons for the adjustment failure can be mechanical:

  • Strong vibration damages the protective cap, causing all three bolts to lose their position.
  • Due to wear on the piston part of the engine. In this case, adjusting the carburetor of the chainsaw will only help out for a while, it is better to replace the worn part.
  • Due to clogging caused by low-quality fuel, scale or damage to the filter. The carburetor requires complete disassembly, flushing and adjustment.

If the chainsaw suddenly stops working, you need to disassemble it to find out the reasons

Chainsaw carburetor adjustment: we analyze all the technical nuances of the work

adjustment of the carburetor of the benzotrimmer

Summer cottage construction and repairs are not complete without the use of a chainsaw, as well as garden maintenance. Due to a malfunction of the tool, all work can get up, so it is so important to be able to disassemble it yourself, find problems and fix them. With sufficient experience and dexterity, it is even possible to adjust the carburetor of a chainsaw. A complicated procedure, or rather, jewelry. How to carry out the adjustment procedures, we suggest you disassemble today.

Chainsaw carburetor adjustment

Gasoline saw. The most demanded garden equipment, which has long been very popular among gardeners and owners of private houses. Not a single event in the field of construction and repair work is complete without it. Well, if we talk about the profession of a lumberjack, then we can say with confidence that such a tool is an essential element, without which there is nothing to do in the forest.

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However, like any complex equipment, the chainsaw requires periodic maintenance. For example, in the case of excessive loads, malfunctions may occur with its operation, which often entail unexpected and very unpleasant consequences.

In our case, we will talk about the device responsible for supplying the fuel mixture to the combustion chamber, namely, the chainsaw carburetor, on the correct operation of which, it depends on how powerful and at the same time economical the equipment will be. Therefore, if you notice a clear error in the operation of your saw tool, the first thing is recommended. Adjust the carburetor.

When is adjustment necessary ?

Inaccurate operation of the carburetor, which can be lost due to the shift of the adjusting screws. Piston group wear The carburetor is clogged (in this case, it is necessary not only to adjust it, but also to disassemble it with subsequent cleaning). Frequent temperature changes combined with high humidity in the room where the instrument is stored. Incorrectly selected fuel mixture (try replacing the fuel, if the result does not follow, adjust the carburetor). Increased vibration level. The engine does not start or stalls after starting. Fast fuel consumption and abundant exhaust.

Carburetor device

The structure of the carburetor may differ in different chainsaws, but the principle of its operation remains the same. A fast air flow moves in the direction of the air duct, the speed of which is regulated by a special valve that closes the outlet. Fuel is sprayed into the duct and mixed with the incoming air stream to create an air / fuel mixture. Then the resulting composition is fed to the engine.

Purpose of carburetor tuning. Ensure the correct quality and quantity of combustible material entering the combustion chamber. In the event of an incorrect ratio, the correct operation of the engine is compromised.

Dismantling the carburetor

Since the carburetor design appears to be the same for all models, the new professional will be used as an illustrative example. Gasoline saw Grunhelm. However, it is worth noting that the problem on which the tool has ceased to function must be sought gradually, from simple to more complex. Disassembling the mechanism, without identifying the reason, can turn against you. But if such a need nevertheless arose, for example, it was required to clean it from dust and dirt, then this should be done very carefully.

Step-by-step instruction :

Carefully remove the top cover by twisting the special plastic screw. Inside we will see a component of the air filter, which also needs to be removed. To get full access to the carburetor, take a screwdriver in our hands and unscrew the three screws located on the sides of the case. Then we remove the fuel pipe and the drive rod. Carefully remove the cable end and disconnect the petrol hose. Having done all these manipulations, we finally release the carburetor.

Do not forget that its design is rather complicated, so it is worth removing all the elements with increased accuracy. The contents of a carburetor are made up of a large number of small parts that can easily get lost.

After disassembly, it is necessary to troubleshoot the mechanism, replace deformed or worn parts, clean and dry the entire set. Make sure the air filter is not clogged with dirt and dust. Then reassemble in reverse order.

Precision work must be carried out exclusively on a hot engine. Therefore, start the engine and warm it up for 10 minutes. Then stop the chain by turning the adjusting screw counterclockwise.

Place the tool on a firm, level surface before starting carburetor adjustment. Point the saw head in a direction safe from injury. Remove objects that are near the cutting edges of the tool.

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To adjust the operation of the carburetor, three screws are used, each of which has its own designation:

H. Controls the main jet for adjusting the high speed.

L. Controls the idle jet, it is intended for setting low rpm.

T. Setting of idle speed.

Adjustment is carried out with screws “H” and “L”. To lower the octane number of the chainsaw, the knobs are scrolled from left to right (clockwise). This procedure increases the engine speed. To increase the octane number, the screws are turned in the other direction, from right to left. Thus, low revs are set.

The adjustment sequence looks like this: L → H → T.

Turning the screw “L” to the maximum, from left to right or in the opposite direction, we find the limiting number of rotation. Then we return to ¼ turnover.

On a warmed-up engine, according to the same principle, we perform actions with the screw “H”. Let the saw run for a few seconds. Armed with a tachometer or good hearing, we determine the maximum speed by sound. It must correspond to the value indicated in the instrument passport.

If the chain is in motion at idle speed, turn the regulator “T” in the same direction until it stops completely.

Draw your attention to, that in the case of inaccurate determination of the rpm point by the regulator “H”, the engine will fail and it will require expensive and time-consuming repairs.

The idle speed is adjusted with the “T” screw. The regulator rotates counterclockwise (right to left) until the chain stops completely.

When adjusting the carburetor correctly, you should observe:

Fast acceleration of the engine. Distinct engine sound, like a four-stroke mechanism. No movement of the chain when idling.

We hope that our article helped you solve such a problem as adjusting the carburetor of a chainsaw, and you can carry out this maintenance yourself. If you have doubts during the adjustment process, then it is better to entrust this process to the employees of a specialized service center, which has all the necessary components for the repair of equipment.

Lawn mowers carburetor device

The basis of the carburetor for lawn mowers is an aluminum body. It contains a diffuser (hole with internal contours). Air is blown through this hole. The flow rate of oxygen (air) depends on the cross-section (orifice) of the diffuser.

The diffuser is equipped with fuel channels. Fuel is drawn in from them using an air stream.

Outside the carburetor is installed:

  • Fuel pump;
  • Jet system;
  • Fuel-air mixture control system;

The main problems and malfunctions of the carburetor.

Mesh filter. There are often only two problems with this element:

  1. Blockage.
  2. Breaking.

In order to find out the cause of the breakdown, the fuel filter cap is unscrewed to remove the strainer. If dirt just accumulates on it, then flushing in gasoline or blowing will help.

If there is visible damage to the mesh filter, it is imperative to install a new one. There may also be damage to the fuel supply pipe (during repair, they practice checking this element).

The carburetor starter in most cases does not function due to blockages. Use acetone or the same gasoline for flushing.

Blowing compressed air into clogged carburetor parts is an acceptable and convenient repair practice.

Do-it-yourself lawn mowers carburetor adjustment

Lawn mowers, like all gas powered garden tools, are not difficult to maintain. It is possible and necessary to repair, configure yourself. For example, adjusting the carburetor of a lawn mower with your own hands is a matter of five minutes.

A lawn mower carburetor is a unit in the power system. In it, like any carburetor, there is a process of mixing air and fuel (gasoline) for further supply to the engine cylinders.