How To Repair A Petrol Cutter

How to repair a chainsaw What should a lumberjack do if a chainsaw malfunctions? But what if the breakdown of the chainsaw is serious enough, or even beyond repair?

How to repair a chainsaw

Every lumberjack systematically has to deal with breakdowns of his main chainsaw tool. How lumberjack, in this case, how to get out of this situation? In different ways: he repairs his chainsaw himself, entrusts the repair to a more experienced colleague in the shop (in the brigade), or gives it to the service.

What should a lumberjack do if a chainsaw malfunctions?

Of course, a lot depends on the prevailing circumstances: when and where this saw broke, how serious is the breakdown, how important is the current work process (work) in this annoying incident, the presence of a repair tool, etc.?

Let’s try to figure out how, so to speak, cost-effective, practical, profitable (if you want) to engage in self-repair of a chainsaw under the circumstances described above.

There are different ways to solve such problems. If a breakdown occurred at the cutting area at the beginning or during the height of the working day, and the stock of harvested timber is not enough, then for a while it will be more practical to use another saw, which is used by a colleague in the brigade, either a crosscutter or a chipper. I understand that in understaffed brigades (today this is the norm) the feller himself performs the function of the logger with his own tool. In this case, there is only one way out to take the chainsaw from the lopper. In this case, it should be borne in mind that you cannot cut forests with household chainsaws, otherwise you will kill this unit of the tool. As a last resort, the lopper chainsaw that the feller will temporarily use should be a semi-professional (farmer), but in this case the tool should be used with care, avoiding heavy loads, especially in large forest.

Of course, there are times when a feller, in the event of a breakdown of his felling saw, uses household appliances. Everyone in the brigade is aware that if the khan does not come now to this baby, the consequences will be felt in the future. However, if the owner of the cutting area appreciates every working day and counts every cube, and a pretty penny, then it is easier for him to purchase another saw for a delimber. The process of logging and hauling must not be stopped! Why?

We can observe a similar picture in the case when the logging team is at a considerable distance from the base or on duty, when it makes no sense to return to the enterprise (warehouse) for another chainsaw, the daylight will end, you will waste gasoline on the car. In addition, timber trucks will arrive at the plot, which will be very costly to release back empty. Such variations, such an unfavorable scenario, can be multiplied. However, it all comes down to one thing, you need to troubleshoot your felling chainsaw. Otherwise, the feller can be safely blamed for his incompetence, and he will collapse the whole process of harvesting and earning a brigade, timber trucks, as well as (if any) a sawmill, carpentry, etc. Of course, initiative is punishable as they say among our people. However, there are times when a lot depends on a competent decision made by a feller.

But what if the breakdown of the chainsaw is serious enough, or even beyond repair? No special tools and spare parts. And the spare chainsaws grunted? Indeed, in our time there are brigades (sabbath), which have only two chainsaws in the presence of felling and delimbing! And behind everyone is waiting.

As I said, a lot depends on the circumstances, as well as the experience of the feller and the brigade of experience, not skills!

Of course, if a line of timber trucks is waiting behind, as well as a sawmill and carpentry, then this already speaks of the incompetence (I would even say about inadequacy) of the head (or manager) of the logging and processing enterprise himself. Two units of gasoline-powered saws in the brigade is, to put it mildly, insanity.

If, nevertheless, a similar scenario has occurred (away from home / base), the chainsaw cannot be repaired and replaced, then you need to contact by mobile communication and let another chainsaw be delivered to you. But this, as I repeat once again, is reasonable if the breakdown happened in the first half of the day, and the timber trucks are already in the plot. With this state of affairs, it is possible to pile on a couple of machines when the saw is delivered to you. Of course, this example does not work with a watch. If there are no timber trucks and the hauling is tolerated, then, of course, it is necessary to return to the base and repair the tool.

What tool is needed

When working in a felling area, a feller must have at least a universal wrench (spanner spanner), which is supplied with the saw, as a rule, from Stihl or Husqvarna. It is advisable to have with you keys such as an asterisk or hexagon. However, if you don’t have special pockets on your work clothes, then at least have a set of these keys in a logging house or in your car.

By the way, in the car / booth it is necessary to contain a set of keys, both end and open-end keys. In the same place, have high-quality screwdrivers, along with specialized ones, which came with a broken chainsaw. Pliers, a knife, side cutters, a hammer to the same repair shop of a car or a heating house. It is advisable to have pullers (you can make yourself), a small forging iron with a blowtorch and a tester (to fix the crankshaft).

As for spare parts: cord coils, circlips, needle bearings, shock absorbers.

About qualification knowledge

Anyway, if lumberjack wants to repair the chainsaw personally in the forest or at the base (enterprise), then he needs knowledge and skill in this craft. Sometimes the state of affairs forces the lumberjack, let’s say, to forcibly eliminate the malfunction of his tool, since the employer saves on this matter.

In fact, a feller must know the entire structure of a chainsaw, the main components and be able to eliminate minor breakdowns. This should be taught in specialized courses, take an exam and issue a crust certificate. But not all fellers are certified, and even without experience, personal troubleshooting without a good mentor will lead nothing to good. Many loggers who do not have crusts, but with solid experience in logging, are able to plug many specialists into their belts. The main thing, as in other spheres of activity, is life experience, skills, individual abilities of a person.

I think many people understand that repairing a chainsaw with your own hands saves time, does not allow stopping the work process. In addition, our own repair helps to build up additional experience, knowledge in the design of the tool, its main units, and to understand their functionality. Yes, in fact, your authority in the team, among colleagues, will increase, and no one will question the status of a specialist.

Since this blog is intended primarily for lumberjacks, we will consider the malfunctions of such world brands as Husqvarna and Stihl, which have proven and consolidated themselves in the domestic timber industry for more than a decade. We will touch on other models if necessary, but we will definitely not consider Chinese models!

What are the most common faults and how to fix them?

We list below the main malfunctions and breakdowns of chainsaws, which the lumberjack is able to fix on his own without resorting to service repair centers:

Repair of the brake of the drive mechanism;
Chainsaw starter repair;
Repair of the chainsaw ignition unit;
Carburetor repair;
Chainsaw coupling repair;
Repair of the piston group.

We will consider and discuss these types of faults in subsequent articles on the blog. So stay tuned to the blog, subscribe to the latest articles on the main page in the right sidebar, or follow this link and share with your friends about it on social networks.

About qualification knowledge

I think many people understand that hand-held repair of a chainsaw saves time, does not allow stopping the work process. In addition, our own repair helps to build up additional experience, knowledge in the design of the tool, its main units, and to understand their functionality. Yes, in fact, your authority in the team, among colleagues, will increase, and no one will question the status of a specialist.

How to repair a chainsaw

Every lumberjack systematically has to deal with breakdowns of his main chainsaw tool. How lumberjack, in this case, how to get out of this situation? In different ways: he repairs his chainsaw himself, entrusts the repair to a more experienced colleague in the shop (in the team), or gives it to the service.

What should a lumberjack do if a chainsaw malfunctions?

Let’s try to figure out how, so to speak, cost-effective, practical, profitable (if you want) to engage in self-repair of a chainsaw under the circumstances described above.

As I said, a lot depends on the circumstances, as well as the experience of the feller and the brigade of experience, not skills!

What tool is needed

As for spare parts: cord coils, circlips, needle bearings, shock absorbers.

What are the most common faults and how to fix them?

We list below the main malfunctions and breakdowns of chainsaws, which the lumberjack is able to fix on his own without resorting to service repair centers:

Repair of the brake of the drive mechanism;
Chainsaw starter repair;
Repair of the chainsaw ignition unit;
Carburetor repair;
Chainsaw coupling repair;
Repair of the piston group.

Petrol mowers malfunctions and how to fix them

Any type of petrol brush has a hollow rod, in which a connecting cable is placed between the engine shaft and the lower gearbox, which transfers rotation to the working body with the cutting tool. In the upper part there is a carburetor and a motor, at the bottom a gearbox and a working tool, covered with a casing. In the middle part there is a transverse handle in which the control buttons are located. To unload the arms, there is an unloading belt that holds the bar with the operator’s torso.

This follows, the repair of petrol cutters is to troubleshoot;

The engine does not start;
The cutting mechanism is not picking up speed;
The engine stalls;
The reducer is heated;
Extraneous knocking is heard, strong vibration of the bar.

Before eliminating the malfunction, you need to diagnose, determine the non-working unit.

It is important to know the lubrication points of the tool. Constant care, cleaning the device after work will extend its life. Before work, it is necessary to tighten the fastening bolts, prepare the fuel and fill the tank.

Chainsaw engine won’t start

If the mechanism does not start, immediately stalls, check sequentially:

Is there fuel in the tank;
Serviceability of the spark plug;
Cleanliness of the air and fuel filter;
The cleanliness of the breather and outlet.

It is necessary to make sure that the candle is working, it gives a spark when it comes into contact with the body. In this case, it is necessary to dry the candle channel, clean and dry the part itself. You can change the candle, but the channel must still be dried for 40 minutes. Check the health of the high-voltage wire, there may not always be a contact. A malfunction in the ignition unit when repairing a petrol cutter cannot be eliminated with your own hands.

If, when the air filter is removed, the engine does not stall, the reason is that it needs to be replaced or cleaned. Replacing the fuel filter is done with great care. Then check the cleanliness of the breather, remove the muffler mesh and clean the exhaust channel.

The next step will be to repair the carburetor, where you have to find the problem and fix it, taking into account the tiny size of the parts. If the simplest operations have not yielded results, in order not to disrupt the fine tuning of the system, it is better to entrust the repair to a specialist. Where to start diagnostics and how to properly repair petrol cutters with your own hands, check out:

Repair and lubrication of the petrol cutter gearbox

The role of the gearbox is to transfer the torque from the motor shaft to the cutting tool through 2 gears with different numbers of teeth. The torque is transmitted at an angle of 30 0. The number of revolutions of the lower cutting blade is 1.4 times less than the engine speed. Gears must be clean and lubricated. To supply oil to the teeth, there is a hole under the screw on top.

First, the place where the plug closes the hole should be cleared of soil and grass. Unscrew the plug with a suitable tool, it is included with the saw. We use a grease tube. Either a native lubricant from the manufacturer is selected, or well-known high-quality compounds, such as Oleo-Mas, Litol.24, Azmol 158. We open the protective layer of the tube and lay the instrument on its side. Slowly rotating the knife, squeeze the grease into the gear housing. The gears, turning, carry the composition with teeth over the entire surface. You can also pour grease with a special syringe.

Too little or too much lubricant can cause the gear unit to heat up. An audible knock and backlash indicate a broken bearing or dirt from a damaged boot. Bearings must be replaced using a puller, without using the heating method.

If the gearbox staggers and runs on the rod, it is necessary to replace the housing, or temporarily tighten the knot with a clamp to secure it to the pipe. If the knife stops rotating, it means that the gears do not engage; the teeth are worn out or crumbled. A pair will need to be replaced with a complete disassembly of the assembly.

When replacing the gearbox, it is necessary to select a new unit, guided by:

Pipe diameter;
The diameter of the drive shaft;
Section of the drive shaft;
Method of fastening protection

Can I repair petrol cutters myself?

At first glance, a simple device for mowing grass with a two-stroke engine is fine-tuned. Repair of petrol cutters must be entrusted to a specialist or to study the technique yourself, using the operating instructions. The streamer maintenance is essential. Gearbox lubrication, line replacement, and teeth sharpening can be done on our own.

Caring for the cutting units of petrol cutters

The saw headset dulls or wears out over time. The tool becomes tense, the load increases, and the swath quality deteriorates. Metal saw blades are sharpened, plastic ones are changed.

If a fishing line is used as a cutting tool, it gradually wears out, and new material is installed in the spool. The principle of operation of the line cutter is to gradually unwind the coil under the influence of centrifugal force. On contact with the grass, the fishing line is abraded, it is fed from the reel gradually. A special winding is needed so that two cutting elements come out at the same time and do not get confused with each other.

The figure shows how to properly wind the line on the reel of the petrol cutter. Before winding a new line, you must:

Unscrewing the nozzle, carefully remove the cover, holding the spring with your hand;
Remove scraps of old fishing line from the reel;
Measure 5 meters of a new string and fold it in half;
In the coil, guides for 2 ends, hook the middle part into the recess and wind in the direction of the arrows for each half of the string;
Lead the remaining 20 cm through the special notches at the opposite ends of the coil;
Install the spring and washers, bring the ends of the line out, close the drum with a lid.

Carburetor device gas cutters

The base of the carburetor is an aluminum case. It contains a diffuser (hole with inner 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;

Do-it-yourself carburetor adjustment for petrol cutters

Petrolcutters, like all petrol powered tools for the garden, are not difficult to maintain. It is possible and necessary to repair, configure yourself. For example, adjusting the carburetor of a petrol cutter with your own hands is a matter of five minutes.

The carburetor from the petrol cutter 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.

The main problems and malfunctions of the carburetor.

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

Blockage.
Breaking.

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

If there is visible damage to the strainer, 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 carburetor parts is an acceptable and convenient repair practice.

The principle of operation of the carburetor petrol cutters

The throttle valve determines the amount of air to be supplied, and the engine power directly depends on this.

Fuel is sucked into the carburetor system by a pump (its membrane). Then it passes through the union in the carburetor. The fluid then flows through the pump inlet and outlet valves. Filtered by the grid. It moves through the needle valve into the membrane chamber.

Phased operation of the device:

Air supply to a tube with an air baffle (damper). The baffle regulates the intensity of the air flow.
The fuel supply system is necessarily narrowed by a diffuser to increase the flow rate.
Gasoline through the float chamber and the nozzle tube with a constriction. A float chamber adjusts the temporary volume of gasoline. In the float chamber, the pressure level is neutral, and in the tube with a constriction it is already low. Due to the differential pressure, the fuel flows through the jet.
The acceleration of the air flow facilitates the transfer of fuel (gasoline) and its atomization. As a result, an air-fuel mixture of the required proportion or density is formed.
The air / fuel mixture enters the engine cylinder through the fuel pipe.

Installing or replacing the starter spring for brushcutters, motor-drills, trimmers

But what if everything is in order with the rope, and the reel (pulley) of the starter does not unwind? Let’s consider this issue step by step using the example of the starter of the gasoline ADA GroundDrill motor drill, which has a pulley with two metal antennae for 2 hooks.

In the case of other types of manual starters of a similar design, which are widely used in gasoline brushcutters, trimmers and motor drills, the whole process of repairing the starter will look similar, differing only in some nuances.

How to repair a gasoline tool starter with your own hands?

In the case of a break in the starter cord, everything is clear: we take out the old rope, take the one that is suitable in length and thickness (linen can be used), pass it through the hole in the reel, tie a knot. Next, we charge the spring to the number of revolutions we need, only after which we fix the handle and voila! Details on how all this is done is clearly shown below.

DIY gas drill starter repair, petrol cutters, trimmer

Today, we will consider the most common case when the breakdown is not so serious and show how to repair the starter with our own hands if the cord breaks off without any destructive consequences or does not wind up due to the fact that the spring inside just flew off, out of engagement. At least initially I want to believe in it. But in order to find out whether this is true or not, you need to disassemble the starter.

Starter repair: disassembly

We unscrew the screw with which the pulley is attached to the starter cover. We take out the antennae, the spring. We pull out the pulley itself carefully so that the spring does not bounce into the face. Even with the most careful disassembly, it usually immediately flies out of the coil and turns abruptly into a long metal strip or twists into rings.

Pull out the white starter coil carefully, do not get hurt by the spring!

If the spring has burst or one of its hooks breaks, then it is simple and quick to repair the starter; replacement of the spring is required. In order not to spend money on the purchase of a new starter, you can only look for it on sale.

If the starter spring simply breaks off, that is, one of the hooks is out of engagement, it is enough to insert it, if necessary, slightly tightening the hooks more tightly (just do not break it off!) Install the spring with an outer hook into the pulley groove and start twisting it, while holding inside the coil and prevent it from jumping out of there.

Refueling the starter spring

Pressing the spring to the pulley, wind the spring inward in a circular motion

It may not seem so easy to insert the starter spring the first time, but everything comes with experience. With a little practice, you can easily wind the spring into the pulley in a maximum of a minute.

The starter spring is wound. It remains only to assemble the starter and charge the spring to the desired value

How to assemble a starter?

The most important thing in the process of self-repairing a starter is to assemble it correctly.

After the spring is fully wound, carefully turn the coil over and insert it into the starter housing so that the second spring hook fits into the housing groove.

When installing the pulley (this one is black), we look through the hole in it so that the spring hook falls into the groove on the starter cover

Then, if there is a spring under the screw, we first install it, not forgetting to put washers on top and bottom of the spring.

Carefully insert the cup with antennae into the grooves of the coil and tighten the screw.

Make sure that the washer on the spring does not fall out. Why is it important? The fact is that the spring scratches the plastic cup with its end, as a result of which the latter wears out and begins to press the screw more tightly against the coil. For this reason, a situation may arise that is very similar to a spring break: the handle is pulled out of the starter, but does not come back. However, loosen the starter screw this problem disappears. It is easy to fix such a starter malfunction: just select a spring of the same diameter, but slightly longer, or put an additional washer. If we just loosely tighten the screw, then it will twist and fly out, and this will increase the likelihood of a spring breaking, since the pulley will not fit snugly enough to the starter housing.

We screwed the coil to the body, now we need to tighten the spring. Before this, it is necessary to remove the starter handle from the rope in advance. If the knot is too strong, then you can simply cut it off or try to untie it, for example, using a pair of pliers. This is so that after you have cocked the spring, you can thread the rope through the hole in the starter cover. The other end of the rope must be fixed in the reel even before it is installed in the body; the rope must be wound onto the pulley before pulling the spring, you do not need to do this after.

Before charging the spring, estimate how many turns of the reel the rope should be wound. Let’s say the length of the rope at the starter of the Ada GroundDrill-5 motor drill corresponds to 5.5 turns around the reel. In this case, we make at least 6 turns of the coil in the direction opposite to the direction of winding.

So let’s get started. Without winding up, insert the rope into the groove in the reel specially designed for it. Everything is ready, we proceed to tensioning the spring. To do this, rotate the coil counterclockwise in the direction opposite to the direction of rotation of the coil when winding the rope. It is more convenient to do this not on the knee, but by pressing the starter with one hand to the floor, and with the other turning the reel directly by the rope attached to it. If experience is not enough, then you can rotate the pulley itself with both hands, but the rope will get in the way, which can create additional inconveniences. After the required number of revolutions is done, we pass the end of the rope through the hole in the starter cover, put on the handle, and fasten it with a knot. It is more convenient to do this together with a partner, so that the end of the cable does not accidentally wind up inside the starter.

By the way, on your own you can make some modifications to the design of the starter in order to more reliably fix the end of the spring inside the coil. At this point, who has enough imagination for that. Now I will explain why this is needed. It often happens that the spring in starters of this type, after the first such self-repair and installation of the starter on the unit, after a few jerks flies again, the hook does not hold in the groove of the coil. And this is despite the fact that the coil almost snugly adheres to the starter cover and the spring there certainly should not hang freely up and down, and even more so until the spring leaves its engagement. It turns out that when the cable is pulled, the spring pulls out, pulls it out of the groove. In this case, you can do the following: cut out a narrow strip of metal, which in thickness could squeeze tightly into the groove of the coil together with the spring hook itself. So the hook will not dangle freely in the groove, which means it will not be so easy for it to break out.

A metal plate tightly inserted into the gap between the spring hook and the groove walls will securely hold the spring

Another solution to the problem: drill small holes in the coil on both sides of the groove and, inserting the spring hook, fix it with a thin wire threaded through these holes. But here you need to contrive to make sure that this wire does not touch when rotating the starter cover from the inside and thereby does not slow down the pulley. Alternatively, loosely tighten the screw or replace it with a similar slightly longer length. You can think of an option to install some kind of gasket between the cover and the coil.

Does your power tool starter design differ from the above? Faced another malfunction, or do you know the best way to repair a starter yourself? Ask questions, share your experience with other joint efforts, we can solve the problem of frequent starter breakdowns once and for all!

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