How to clean the carburetor on a Chinese chain saw

How to wash a chainsaw carburetor without disassembly

Cleaning the carburetor of a chainsaw of any modification, configuration and power takes place according to one traditional and correct scheme, and its necessity arises as a consequence of clogging the part. To understand that it is time to clean the carburetor. you can observe how the saw starts and immediately stops, perhaps still “fluffing”, making the desired rpm. Anyway. with your own hands to clean the carburetor. it is quite real, because our specialists have presented instructions and demonstrated how to do it quickly and correctly. Regarding the literacy of cleaning, it is not only about using certain agents, fluids, but also the format of blowing, assembling the carburetor back, as well as checking its readiness for future work.

Sometimes parts on a chainsaw do not need to be repaired and cleaned, but replaced in a timely manner. Therefore, as long as your carb can still be cleaned and return it to its original working condition. use the tips from KosiKos, and let your mechanism be healthy!

How to clean the carburetor on a chainsaw with your own hands

Before cleaning the carburetor on the chainsaw, let’s understand the situations when it is necessary to clean it:

There are situations that cleaning the carburetor does not help, then you need to replace the repair kit, if after this procedure nothing has changed in the work of the chainsaw. check the rubber adapter that are between the cylinder and carburetor (in its place may be a rubber adapter with a brass insert). Let’s remove top cover, filter, long bolts, adapter, disconnect pipes from carb and take it out. The cleaning process itself:

• first need to clean with a fluffy brush from external dirt and dust, so that it does not get inside during disassembly;
• start with the bolt “H”, which is responsible for the upper operating position of the carburetor, at maximum revolutions. Screw it in, counting and remembering the number of turns, for example, 2.5. Further we unscrew it
• screw in the screw “L”, which is responsible for the low revolutions. For example, 4.5 turns. Write down the readings and unscrew it;
• remove the top and bottom cover with a screwdriver, unscrewing the bolts. It is better to do it not on the ground, but on a hard non-slippery surface;
• Take out the needle;
• If the gaskets and membranes are badly worn and frayed. they also need to be replaced with new ones. You can order the carburetor repair kit for Husqvarna, Leader, STIHL or Partner saws in KosiKosa store;
• You can often see the following picture before cleaning. there is a lot of dust and debris in the “sump” and other containers;
• clean carb, pre-wet it in solvent, then blow it out with compressed air using a compressor. repeat this procedure 2 times. Separately clean the diaphragms and put them back together. First we put the needle back in place;
• The rocker arm support is mounted back on the needle;
• press off the spring and squeeze out the fixing bolt;
• put the diaphragm, bottom cap and fasten it with bolts (remember or write what kind of bolts were used to fasten it);
• put the upper diaphragm with the cover also in place and bolt it down;
• put the screw “L” up to the stop and then unscrew it 4.5 turns (as an example), as it was on the carburetor, and the screw “H” also screw up to the stop and unscrew the same 2.5 turns (as an example), keeping the previous settings. This is necessary in order not to lose the settings;
• put the carburetor back in the chainsaw to check, putting it on the throttle;
• the hose coming out from the cylinder is put on top, the hose coming out of the tank is on the right side of the carburetor and the hose that goes to the primer is on the left side;
• put two bolts in the adapter and put it in place;
• close the choke, press the primer several times (enough10);
• we try to start the tool.

As you can see, with your own hands to clean the carburetor your tool is not difficult at all, if you follow the instructions, chronology, fix yourself the revolutions of the screws maximum and minimum, to assemble the unit exactly in the opposite order. KosiKosa power tool store demonstrates a quality video, where the whole instruction is vividly supported by a clear example.

Disassembling the chainsaw

Before we proceed directly to the disassembly of the saw, first we need to clean it. All operations have to be done carefully and slowly. To prevent the fasteners and small parts from getting lost, it is possible to use containers, in which elements of the structure are stacked during disassembly. Disassembly begins with loosening the screws that hold the clutch cover, then loosen the chain tension. only after that the bolts can be unscrewed completely. Then the clutch lining, tire and the chain itself are removed. The next step is to remove the upper housing cover. Use a brush and compressed air to clean the pinion drive unit. this is usually the most contaminated area. Locations with oil leaks are best cleaned with gasoline.

There may be several reasons why the chainsaw won’t come off:

• the throttle plate spring is broken;
• throttle trigger seizing;
• the throttle linkage is bent;
• Throttle shaft corkscrew is lost, causing it to jam.

To solve all these problems is not difficult, you need to conduct a careful inspection and accurately determine the cause, and then replace the faulty part. As a rule, if a chainsaw recovers speed well, runs at idle and has normal power, the problem is that it does not reset, purely mechanical. And finding and fixing mechanical problems is much easier than determining and stopping air leaks in the chainsaw’s crankcase.

The preparatory step

Repair of any machine should begin with a preliminary step and the STIHL 180 is no exception. The first step is to remove the side cover, chain and guide bar from the STIHL 180 long before disassembling. Next, with a compressor and a brush, you need to clean the chain saw from the dirt, sawdust, oil stains, and the rest.

When cleaning the saw, special attention should be paid to the place where the chain saw’s drive sprocket is located, i.e. к. This is the dirtiest part.

Where there is a lot of oil, of course wash with unstained gasoline.

Why the chainsaw shoots into the carburetor?

The main cause of this malfunction is improperly set distance between the ignition elements of the gasoline-powered tool. Because of this, fuel that enters the internal combustion engine cylinder does not have time to be completely combusted in it. The result is a sound like an explosion. To effectively solve the problem, you need to adjust the ignition of the gasoline tool by following the instructions in the owner’s manual.

If during the start and operation of the tool, its owner hears sounds reminiscent of gunshots, it indicates a malfunction of the node in which the fuel is mixed. This is most likely caused by such malfunctions in the chainsaw carburetor:

• Over-tightened ignition. in this case, the fuel does not burn through, resulting in specific sharp shots;
• Feeding into the carburetor a mixture with a low concentration of gasoline. to fix the problem, you will need to adjust the jets.

If the shooting sound comes from the side of the muffler, the problem is caused by oversaturation of the fuel mixture with gasoline. If there is too little air in the fuel, it will burn not only in the chamber but also in the muffler. This is evidenced by a large amount of soot on the inner walls of the muffler.

When adjustment is needed

The carburetor needs adjustment:

• If the settings are lost due to loose screws or vibration, or when trying to adjust the unit.
• If the cover is broken.
• To find out why the design does not work.
• When the engine fails to start or falters and then stops immediately.
• When the chainsaw fires into the carburetor or “sneezes.
• The chainsaw vibrates heavily.
• To check what is causing the fuel overrun.
• If there is a thick exhaust.
• If there is no gasoline in the machine.
• When the spark plugs are blackened or fouled.
• The saw can’t run at high RPM and increase the power.
• Check the engine if it shuts off when revving.
• The air-cleaning system was malfunctioning.
• Debris has entered the mixture distribution system.
• The pistons are worn out.

It is also necessary to perform adjustments in case of fuel grade change and humidity fluctuations.

When adjustment is needed

Carburetor adjustments need to be made:

• If the settings are lost due to loose screws or vibration, or if you try to adjust the unit.
• If the chain saw cover is broken.
• To find out the causes of malfunction.
• When the engine won’t start or falters and then shuts down immediately.
• If the chainsaw fires into the carburetor or sneezes.
• The chain saw vibrates a lot.
• To check why the fuel overrun occurred.
• When you get a thick exhaust.
• If there is no gasoline in the machine.
• When spark plugs turn black or have fouled.
• The saw can no longer perform at high RPM and does not produce more power.
• Check engine if it shuts off when revving.
• If the air-cleaning assemblies are malfunctioning.
• Debris has entered the mix distribution system.
• The pistons are worn out.

Also adjust if you change fuel brand and humidity changes.

Why does the chain saw shoot the carburetor??

The main cause of this malfunction is the improperly aligned distance between the ignition elements of the gasoline tool. Because of this, the fuel that enters the standard cylinder of the internal combustion engine, does not have time to burn completely in it. As a result, there is a sound similar to an explosion. To effectively solve the problem, you need to adjust the ignition of the chainsaw by following the instructions in the owner’s manual.

Not seldom such chainsaw carburetor failure is the result of a depleted or over-enriched fuel mixture getting into a cylinder. To fix the failure, you need to adjust the metal throttle and the regular fuel jets.

Chinese models

Adjusting the carburetor of a Chinese chainsaw, for example, Carver, is done in much the same way as the factory models. There are the same three basic adjusting screws L, H, T. Sometimes these models have the possibility of adjusting the idle speed. But as a rule, workers of specialized services and owners of such saws say that it is not always possible to set up a quality Chinese chainsaw immediately.

For classic Chinese models the screw L should be 1.5 turns off from the maximum value. The H screw should be set one turn back from the maximum setting. Idle RPMs are regulated the same way.

Thus, independent adjustment of the carburetor of a chainsaw is not a very difficult process and can in most cases be carried out by a self-taught person.

Fuel feeding

In addition to the above-mentioned clogged breather, there may be other problems in the fuel supply. The main obstacles may be:

Fuel filter clogging. To check the unit for this malfunction, you need to disconnect the fuel hose and see how the fuel flows. If you get a weak jet, you may need to clean the filter. The filter device is taken out through the filler opening of the tank and cleaned, if the contamination is too severe, it is replaced.

Professionals recommend changing the filter every few months, regardless of dirt.

Lack of fuel. In this case, the problem may lie in several factors. The first is the contamination of the air filter. The problem is that not enough air is delivered to the carburetor, resulting in poor engine performance. The filter must be removed, cleaned, rinsed and dried, then adjusted again.

Second cause. unadjusted carburetor. Her, t. е. the adjustment is made with three screws.

And the last cause is a problem with the diaphragm monolith or contamination of the carburetor ducts. As for the other cases it is necessary for the accessories to be dry and clean.

How to properly adjust the carburetor on a chainsaw with your own hands

The factory settings of the chainsaw’s carburetor provide for optimal fuel and air intake. But during operation, they can go astray because of vibration. a shift of even ¼ of a turn at any of the screws can lead to a serious change in the parameters of the preparation of the air-fuel mixture and it is necessary to adjust the carburetor chainsaw.

The chainsaw carburetor is adjusted with three screws marked H (High), L (Low) and S. The last one has different names, depending on the brand and make, such as T or LA.

• H: is responsible for the operation of the main jet and regulates the maximum speed.
• L: adjusts the idle speed nozzle position and lets you set the RPM.
• S/T/LA: it is intended for adjusting the idling speed of the motor.

To know how to properly adjust the carburetor on a chainsaw, you need a data sheet. it contains information about the angles of rotation of the adjusting screws. Then we proceed directly to the adjustment. By the way, here you will need a screwdriver to adjust the carburetor of a chainsaw or an ordinary flat screwdriver:

• Place the chainsaw on a flat surface, preferably a table or something similar. IMPORTANT: Always position your chainsaw so the bar is facing in the opposite direction. The engine must be shut off.
• Using a wrench or screwdriver, unscrew the housing cover and remove it to reach the carburetor.
• Remove the air filter that covers the carburettor for the chain saw. The manufacturer may install a foam cushioning insert on top of the carburetor. this should also be removed.
• Now begins the adjustment of the chainsaw carburetor. Screw L and H as far as they go. Tighten them slowly and carefully so they do not break.
• About 1.5 turns unscrew both screws.
• Start the engine and let it run for about 7-10 minutes to warm up well. a cold engine will not adjust the carburetor chainsaw.
• After the engine has warmed up, set it to run at medium rpm.
• Slowly start turning the idle speed screw counterclockwise. Crank it until the engine will not run smoothly. If the engine begins to stall, you need to continue adjusting the carburetor of a chainsaw and return the screw clockwise, little by little.

After the adjustment of the carburetor of a chainsaw of Chinese manufacture or any other, it is necessary to “drive” the engine at different revolutions.

Why the chainsaw shoots into the carburetor?

If during the start and operation of the tool, its owner hears sounds resembling gunshots, it indicates a malfunction of the node in which the fuel is mixed. The reason for this, most likely, are such malfunctions of the chainsaw carburetor:

• overdrawn ignition. in this case, the fuel does not burn through, which leads to specific sharp shots;
• Feeding the carburetor with a mixture with a low concentration of gasoline. to correct the problem, you will need to adjust the jets.

If the shooting sound comes from the side of the muffler, the problem is in the oversaturation of the fuel mixture with gasoline. If there is too little air in the fuel, it will burn not only in the chamber, but also in the muffler. This will be evidenced by a large amount of soot on the inner walls of the silencer.

How to adjust the carburetor on a chainsaw

Factory carburetor settings on your chainsaw provide optimal fuel and air intake. But they can be lost due to vibration. even a shift in the rotation of any of the screws can cause serious changes in the fuel-air mixture, and it is necessary to adjust the carburetor of a chainsaw.

A chainsaw carburetor is adjusted with three screws labeled H (High), L (Low) and S. The latter may have other names, depending on the brand and manufacturer, such as T or LA.

• H: is responsible for the main jet and regulates the maximum speed.
• L: adjusts the nozzle position at idle and allows you to adjust the low speed.
• S / T / LA: designed to adjust the speed of a single engine.

READ How to Make a Guide for a Circular Saw

To know how to properly install the carburetor on a chainsaw, you need a data sheet. it contains information about the angle of rotation of the adjusting screws. Then go directly to adjusting. By the way, you will need a chainsaw carburetor adjustment screwdriver or a regular flathead screwdriver here:

• Lay the chainsaw on a flat surface, preferably on a table or something similar. IMPORTANT: the chainsaw must be positioned so that the bar is facing in the opposite direction. The engine must be off.
• Use a wrench or screwdriver to unscrew the throttle body cap and remove it to reach the carburetor.
• Remove the air filter that covers the chainsaw. The manufacturer may install a foam cushioning insert on top of the carburetor. it must also be removed.
• Now the carburetor chainsaw tuning begins. L and H screws should be completely tightened. Twist them slowly and carefully so as not to break.
• Loosen the two screws about 1.5 turns.
• Start the engine and let it run for 7-10 minutes to warm up well. it won’t help to adjust the chainsaw carburetor on a cold engine.
• After the engine has warmed up, set it to run at medium speed.
• Slowly start tightening the idle speed screw counterclockwise. You need to turn until the engine starts to run smoothly. If the engine starts to stall, you need to keep adjusting the chainsaw carburetor and gradually turn the screw clockwise.

Having adjusted the carburetor of a chainsaw of Chinese or any other manufacture, it is necessary to “accelerate” the engine at different speeds.

How to clean a chainsaw carburetor with your hands

On the fact that the carburetor needs cleaning, can indicate a number of signs. For example:

• It is hard to start the engine.
• The engine can not get the maximum speed.
• Chainsaw stalls when idling.
• Increase of revolutions leads to engine stalling.
• During operation there is black smoke coming out of the muffler.
• Fuel consumption increases.
• Engine stops on warm-up.

If you see one or more signs of malfunctioning on your chainsaw, you need to clean it. To do this, experts recommend adhering to the following sequence of actions:

• Get a cleaner. You could also use WD-40 thinner.
• Perform disassembly of the carburetor.
• Disassemble the device, starting from the place where the fuel is pumped. the diaphragm pump. To do this, it is enough to unscrew the bolt fastening.
• Remove the top cover. By removing the cover you can access the diaphragm pump.
• The membrane should be clean, elastic and soft. If it is stiff and clogged, it must be replaced.
• Now it is time to assess the condition of the fuel filter screen. If there are any clogs on its surface, they must be removed. To do this, the mesh is removed, and cleaned with a soft brush.
• After that, you need to turn the carburetor to yourself with the back side and unscrew the fastening screws that fix the plate.
• Under the plate there is a second diaphragm that controls the needle, closing and opening the hole through which fuel enters.
• It must also be clean and flexible. Otherwise the second diaphragm will also have to be replaced.
• A small foot is connected to the needle, if it has a bent appearance, it can be gently bent towards itself by 0.5-1.0 mm. If this is not done, the needle will not be able to open fully, reducing the chainsaw’s power output.
• It is now possible to clean the inside of the device and blow out the ducts with a cleaner. It has a long tube with a nozzle on the spout, which makes it easy to work with.

After cleaning is complete, the equipment is assembled in the reverse order of disassembly.

Features of STIHL and Husqvarna chain saw carburetors

The cleaning process does not depend on the brand of chainsaw. The only difference is in the design. STIHL and Husqvarna carburetors have additional jets on the side. They can be made of brass or copper. When cleaning the carburetors of these models, the jets also need to be removed and cleaned.

Timely cleaning of the chainsaw carburetor the unit will operate efficiently and without interruption.