Among the owners of the private sector, a chainsaw is an indispensable tool for which there will always be application. This is a mechanism that consists of parts carefully adjusted to each other. The main element of the whole structure is the carburetor. As in old cars, its role is to prepare a mixture of fuel and air for its further supply to the engine. And since the element works constantly when using the tool, it is necessary to service it periodically. How to adjust the chainsaw carburetor? Every owner of this mechanism wants to know the answer to this question. Actually, we’ll do it now.
Signs of carb adjustment
How to understand that the time has come for the setup? As a rule, this procedure is mandatory when detecting loosening of the adjusting screws.
However, there are other signs that indicate that it is time to adjust the carburetor. In particular, you should pay attention to the following symptoms:
- Sensation of strong vibration - because of this, the protective cap is damaged, which, in turn, leads to loss of fixation of all three adjusting screws.
- Deterioration of the piston of the engine - carburetor adjustment in this case will extend the tool, but only for a certain period of time. In any case, the piston group must be replaced as soon as possible.
- Blockages - their appearance is caused by poor quality gasoline, scale, clogging or damage to the filter.
- Increased "appetite" is a clear reason to think about how to adjust the carburetor on the Shtil chainsaw or any other model. The phenomenon is accompanied by an increase in the amount of exhaust gases, which does not lead to anything good.
- The engine stalls immediately after the factory or does not start at all - this happens as a result of a lack of fuel against the background of excess air.
All these signs clearly indicate the need for carburetor adjustment. And the sooner the procedure is carried out, the better for the instrument. Otherwise, other equally important components of the engine and chainsaws in particular may fail.
How is the carburetor?
First you need to understand how such an integral element of a chainsaw is designed.
And in order to understand how to adjust the carburetor on the Husqvarna chainsaw, let us consider its device using the example of this tool. The whole structure is represented by the following elements:
- Fuel pump. Thanks to this device, the working mixture enters the carburetor.
- Diaphragm. Due to this element, the flow of the combustible mixture into the engine is limited.
- Float chamber. Fuel is collected here, while its level is controlled by a float. As necessary, the fuel is sent to the main chamber, where it is mixed with air.
- The working chamber. Air passes through it, and fuel is injected. Moreover, the amount of the supplied mixture is regulated by the throttle, which is located here.
- Diffuser. This is a narrowed section of the tube that provides air to the place where the fuel is injected.
- Needle valve. Thanks to him, the fuel supply is regulated.
- Jet. These are the screws, due to which the fuel supply is adjusted at low and high speeds, including the idling element.
All this is enclosed in a housing having clamping bolts with a set of gaskets. In the carburetor device, there is another damper in addition to the throttle - it is located at the inlet of the air filter. Thanks to it, the air supply is underestimated, due to which the mixture becomes saturated in order to easily start a cold engine.
The question of how to adjust the carburetor on the Huskvarna 142 chainsaw (or another manufacturer) worries many people living in private households. However, before this, it is still worth getting acquainted with the principle of the carburetor. And more about that later.
Operating principle
The principle of the carburetor is easy to understand. Air is drawn in through the tube at a speed controlled by a damper. This involves the float of the first camera. Passing through the diffuser, the air mixes with the fuel and is immediately sprayed. Next, the finished mixture enters the engine cylinder, passing through the inlet channel. And the more fuel will be supplied, the higher the engine speed.
Regardless of the manufacturer and model of tools, all carburetors have an identical structure and work on a single principle. The difference lies only in the material of the constituent elements and their location in the carburetor body.
Adjustment Tools
How to adjust the carburetor on the Partner chainsaw? First of all, you need to understand the purpose of the three screws that the models 142, 240, 236, 137 and others like are equipped with. Each of them has its own designation and purpose:
- Screw L - with its help low revs are regulated.
- Screw H - they adjust the motor to work at high speeds.
- Screw T - adjusts the idle speed.
Some models of chainsaws are equipped with only one coil with the mark T. Accordingly, the adjustment of carburetors in this case is done by manipulating only one.
In addition, it is worthwhile to understand that regardless of the number of screws, the optimal operating mode of the chainsaw is ensured by the carburetor settings, which were set back in the factory. As for the screws themselves, their presence is due to the operation of the tool under certain weather conditions.
Training
How to adjust the carburetor on the "Calm 180" chainsaw? This procedure requires thorough preparation. And first you need to refer to the operation manual of the chainsaw and find information regarding the angle of rotation of the screws in it. If you do everything in random order, you can simply disable the engine.
The motor itself, in turn, must be in good condition. In addition, you need to inspect the air filter and, if necessary, clean it. Otherwise, it will not let the right amount of air pass and the carburetor will not be adjusted correctly.
The procedure itself must be performed on a flat surface. In this case, the tool itself should be positioned so that its chain is not directed towards the operator in order to avoid personal injury.
Adjustment procedure
The carburetor of the tool with three screws is adjusted by manipulating two of them - L and H. In order to increase the speed, turn them in the direction of rotation clockwise, to lower - in the opposite direction. It is worth using a special screwdriver to prevent it from slipping off the screws and damaging the threads on their “hats”.
The decision on how to adjust the carburetor on the Partner 350 chainsaw involves two steps - the initial and the main. Actually, the algorithm of actions may look as follows:
- The first step is to turn both screws clockwise to the end.
- Then screw L and screw H rotate one and a half turns in the opposite direction.
- The second stage - the chainsaw is started and left for a while to completely warm up. 12-15 minutes will be enough.
- Now you should turn another one - the third screw T until the moment when the engine starts to work stably and the circuit on the bus does not rotate.
In the course of these manipulations should not be in a hurry. The slower the screws turn, the more tangible you can feel the changes in the engine.
Check
With how to properly adjust the carburetor on the chainsaw, we have already become familiar. However, after the procedure, it is necessary to check the “acceleration” of the power unit, the set of maximum number of revolutions and its operation in idle mode.
The engine will pass the test if, during smooth pressing of the accelerator, the rpm from low (2800) increases to maximum (15000) in a short period of time. If this does not happen, then you should turn the screw L counterclockwise. Its turnover should not exceed 1/8 of the full circle.
The maximum revolutions are measured with screw H; in addition, a tachometer is required. The maximum number of revolutions should not exceed 15,000. This is precisely what the mentioned measuring device is for. If there are a lot of them, you need to lower them by turning the screw counterclockwise. If it is necessary to increase them, the adjusting element should be turned in the opposite direction.
Knowing how to adjust the carburetor of the chainsaw is important due to the fact that the further operation of the tool, including its service life, will depend on this. Neglecting the check is also not worth it in order to avoid many problems.
Failures
If after the chainsaw has been started and when the trigger is pulled, the dips feel good during a set of revolutions, it is worthwhile to manipulate the screw L. To do this, turn it no more than a quarter of a full turn in both directions. Along with this, evaluate the response of the motor to gas pressure.
It is necessary to try to find the position of the adjusting screw at which the engine will accelerate quickly and evenly. It should also not be in a hurry, and it does not make sense to turn the screw a wider angle, because on its own it is simply not able to unwind. In this regard, a quarter of the turnover will be enough.
A number of nuances
After adjusting the carburetor, the chainsaw engine should easily gain and slow down. Moreover, its work must be stable, regardless of their number. But if after manipulating the screws the circuit rotates in idle mode, therefore, the adjustment was carried out incorrectly. Then you need to adjust the position of the screw T.
How to adjust the chainsaw carburetor, and do it right? For this, one important point must be mentioned. When setting up the Husqvarna chainsaw carburetor, it is worth considering the response time to the rotation of the screws. The settings do not change immediately, but after 5-10 seconds. For this reason, manipulations should be leisurely.
Another sign that indicates an incorrect carb adjustment is smoke during the operation of the tool, and it is very strong. This is an indication that too much fuel is entering the combustion chamber. In this case, adjustment of screw L. is necessary.
Chainsaws brand "Calm" and "Partner"
In the "Calm" models 180, 250, 361, and "Partner" 351, 350, carburetor settings are made with the same screws as the "Husqvarna" chainsaw - H and L. This sets the proportions of gasoline and air. Screw T is also responsible for setting the idle speed. Although some models may have a different marking for this mode - S. In other words, the adjustment procedure itself, if necessary, is carried out according to a single scheme for almost any model.
Chainsaw running
Buying a chainsaw is no less important than adjusting its carburetor. If it is acquired by hand (which is considered an acquisition in the secondary market), then there are no special problems. However, a break-in is necessary for a new tool. This term is the process of lapping the engine parts and the CPG. And while the chainsaw is being run in, the necessary and correct clearances are finally formed in the engine of the tool. This process is just as important as solving the problem of how to adjust the chainsaw carburetor.
For this purpose, the corresponding settings are still being set at the factory - the speed is 600-700 less than what is required in the usual operating mode. Thus, the break-in process of the power unit is carried out in a gentle mode. For this reason, it is not worth immediately after acquiring a tool to tune it. In any case, this must be done, but not before the run-in ends.