Husqvarna Carburetor Adjustment Key

15th August 2020

Carburetor adjustment key (Toyota, Mitsubishi, Husqvarna) FORCE Carburetor adjustment key (Toyota, Mitsubishi) FORCE

Carburetor adjustment key (Toyota, Mitsubishi) FORCE

Chainsaw chain is spinning at idle speed

If the Husqvarna chain rotates at idle, then it can be concluded that there are malfunctions in the clutch mechanism or the idle is not adjusted. To eliminate the malfunction, it is necessary to remove the saw chain brake cover and inspect the integrity of the clutch spring. Replace defective clutch.

If the clutch is working properly, to eliminate chain spin, it is necessary to correct the idle speed with the adjusting screw marked with the letter (T) or carry out a full carburetor adjustment.

Important: a possible reason for an independent increase in idle speed is the appearance of air leakage into the engine crankcase or carburetor, which can lead to serious damage to the CPG.

Air filter and carburetor

To remove the carburetor, it is necessary to disconnect the fuel hose and throttle rods from it, it is convenient to do this after dismantling the air filter, which is installed immediately behind the carburetor and is held with two nuts 10. After the air filter is dismantled, and the fuel hose and the rods are disconnected, just pull the carburetor towards you and remove it from the studs.

If the saw starts but is bad

The saw can be difficult to start because of a malfunction or improper carburetor adjustment. In the event that the carburetor overflows, the chainsaw will be easy to start on hot, but rather difficult on cold, especially after a long idle time.

An indirect sign of an excessive amount of fuel mixture entering the cylinder when the chainsaw is running is exhaust. If a lot of white smoke is emitted during the operation of the chainsaw, it is worth checking the proportions of preparing the fuel mixture and adjusting the carburetor.

Theory and principles of the fuel system, carburetor design

The main reasons for adjusting the carburetor of the chainsaw:

Gasoline consumption has increased, the device consumes too much oil;
During operation, the chainsaw heats up very much, smokes, makes pops or explosive sounds (such a problem is a signal that you need to clean the muffler, blow the breather, rinse the jets in acetone);
The engine stopped idling;
The chainsaw begins to stall some time after work, in general, the tool has become worse to work. It does not develop power so efficiently, does not develop maximum speed;
The chainsaw vibrates strongly during operation;
It is also necessary to adjust the carburetor if the chainsaw has previously operated on low-quality fuel or an improperly prepared fuel mixture.

Chainsaw carburetor setting:

Adjusting the carburetor step by step:

Turn the screw L from left to right, or from right to left, find the maximum engine speed, then go back 1/4 of a turn;
Do the same with the screw H;
The chainsaw should run for a few seconds, using a tachometer, determine the maximum engine speed. Their indicator should not exceed the maximum specified in the instructions for the chainsaw;
If the chain moves in idle mode, turn screw T in the direction of chain movement until the chain stops completely (idle speed is always controlled only by screw T, which is turned from right to left. Counterclockwise. Until the chain stops completely).

Carburetor accessories

First of all, it is worth figuring out which adjustment screws are provided in the Husqvarna 236 chainsaw.

The manufacturer equipped the model in question with 3 screws:

L-screw adjusts the jet at low revs;
The H-screw is used to adjust the jet at high speeds;
The T-screw is used to adjust the idle speed.

If it is necessary to adjust the supply of fuel, lubricant mixture and air access, the first 2 elements are used. Turning them clockwise, the mixture can be leaner and slower. Performing actions in the reverse order, that is, unscrewing the elements in the opposite direction, the mixture is enriched and the revolutions increase.

The idle speed is adjusted by the third element. Turning it clockwise, the revolutions increase, and to decrease them, the screw is simply turned in the opposite direction.

Do-it-yourself Husqvarna 236 carburetor adjustment

The chainsaw is considered by many to be the ideal and irreplaceable assistant. Indeed, with its help, you can perform all the work that the ax previously helped to do, while not spending a lot of time and effort. That is why almost every home craftsman has such a tool in his arsenal.

The design of the units under consideration is not so complicated. And this means that every craftsman can repair the tool, taking into account the advice of specialists. We will look at the sequence in which the Husqvarna 236 carburetor is adjusted by hand.

Step-by-step adjustment

Experts recommend making an independent adjustment of the carburetor in the model in question, adhering to the following plan:

First of all, you need to adjust 1 screw, then proceed to the second and only lastly, do the adjustment of the screw, which is responsible for idling.
Next, you need to determine what are the largest idle speed. To do this, carefully turn 1 screw clockwise. Having found the largest indicator, the element should be turned ¼ turn counterclockwise. If, during this operation, the chain continues to rotate while idling, the T screw must be slowly turned counterclockwise until the chain stops rotating.
Using the screw H for adjustment, it is really possible to change both the power of the unit and its frequency of revolutions. However, it should be borne in mind that if the carburetor will work for a long time due to the ordinary mixture and at increased speeds, this can cause the chainsaw to fail.
To adjust the screw H, you need to do the following steps:

Warm up the engine of the unit for 15-20 seconds by selecting the full speed mode;
Turn the H-element counterclockwise by ¼ turn;
Leave the engine in working condition for 10-15 seconds;
Using a tachometer, analyze what is the maximum speed;
If the received data do not coincide with the passport, the process should be repeated again.

The four-stroke sound of the engine will help to understand that the adjustment is made correctly. If the mixture after adjustment is too lean, the unit will make a squealing sound. If the mixture is too saturated, smoke will begin to appear from the muffler. If in the arsenal of home craftsmen there is a device called a tachometer, then you can proceed to self-adjusting the H-screw. Under other circumstances, it is better to seek help from specialists.

After the first elements are adjusted, you can start adjusting the idle screw, performing the operation in the following sequence:

Having activated the engine, you should carefully begin to turn the screw T clockwise;
It is necessary to turn the element until the chain of the unit begins to rotate;
In the next step, the screw must be turned in the opposite direction to stop the rotating movement of the chain.

To understand that it was possible to correctly set the number of idle turns will help the uniform operation of the engine, in all directions, with the necessary reserve of turns, during the rotation of the chain.

To independently understand that the work was done correctly, it will be possible to operate the engine, which should instantly accelerate and emit a four-stroke sound at full throttle. If the unit starts with difficulties, the engine cannot immediately accelerate, the first screw must be readjusted again to enrich the lean mixture.

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