Makita EA4300F, EA3500F User Manual

Operator’s and Safety Manual
for Gasoline Chain Saws
EA3500F EA4300F
WARNING!
Read and understand this Manual. Always follow safety precautions in the Operator’s and Safety Manual.
Improper use can cause serious injury! Preserve this Manual carefully!
WARNING!
FUELS WITH MORE THAN 10% ETHANOL ARE NOT APPROVED FOR USE IN MAKITA 2-STROKE ENGINES!
requirements are not approved for use in MAKITA 2-stroke gasoline engines!
USE OF ALTERNATIVE FUELS CAN CAUSE THE FOLLOWING PROBLEMS:
Poor engine performance, loss of power, overheating, fuel vapor lock, improper clutch engagement, premature
deterioration of fuel lines, premature deterioration of gaskets, premature deterioration of carburetors.
USING ALTERNATIVE FUELS AND/OR 2-STROKE OILS NOT ACCORDING TO JASO FC OR ISO-L-EGD IN
MAKITA 2-STROKE ENGINES WILL VOID YOUR ENGINE WARRANTY!
1
EMISSIONS COMPONENT DEFECT WARRANTY COVERAGE
MAKITA U.S.A, Inc warrant to the initial retail purchaser and each subsequent owner, that this utility equipment was designed, built, and equipped to conform at the time of initial sale to all applicable regulations of the U.S.
Environmental Protection Agency (EPA), and that the engine is free of defects in materials and workmanship which would cause this engine to fail to conform with EPA regulations during its warranty period.
For the components listed under PARTS COVERED, the service dealer authorized by MAKITA will, at no cost to you, make the necessary diagnosis, repair, or replacement necessary to ensure that the engine complies with applicable U.S. EPA regulations.
EMISSION COMPONENT DEFECT WARRANTY PERIOD
The warranty period for this engine begins on the date of sale to the initial purchaser and continues for a period of 2 years.
PARTS COVERED
Listed below are the parts covered by the Emission Components Defect Warranty. Some of the parts listed below may require
scheduled maintenance and are warranted up to the rst scheduled replacement point for that part.
Fuel Metering System Ignition System
Carburetor and internal parts Spark plug
Fuel lter, if applicable Flywheel Magneto
Throttle stopper, if applicable Ignition Coil Choke System, if applicable
Air Induction System Miscellaneous Items Used in Above Systems
Pre lter, if exist Fuel hoses, clamps and sealing gaskets Air lter, Air lter case, Intake manifold
Components with evaporative emissions Fuel tank, Fuel tank cap
OBTAINING WARRANTY SERVICE
To obtain warranty service, take your engine to the nearest MAKITA Factory Service Center or service Center authorized by MAKITA. Bring your sales receipts indicating date of purchase for this engine. The dealer of service authorized by MAKITA will perform the necessary repairs or adjustments within a reasonable amount of time and furnish you with a copy of the repair order. All parts and accessories replaced under this warranty become the property of MAKITA.
WHAT IS NOT COVERED
• Conditions resulting from tampering, misuse, improper adjustment (unless they were made by the service dealer authorized by MAKITA during a warranty repair), alteration, accident, failure to use the recommended fuel and oil, or not performing required maintenance services.
• The replacement parts used for required maintenance services.
• Consequential damages such as loss of time, inconvenience, loss of use of the engine or equipment, etc.
• Diagnosis and inspection charges that do not result in warranty-eligible service being performed.
• Any non-authorized replacement part, or malfunction of authorized parts due to use of non-authorized parts.
OWNER’S WARRANTY RESPONSIBILITIES
As the engine owner, you are responsible for the performance of the required maintenance listed in your operator’s manual. MAKITA recommends that you retain all receipts covering maintenance on your engine, but MAKITA cannot deny warranty solely for the lack of receipts or for your failure to ensure the performance of all scheduled maintenance. As the engine owner, you should however be aware that MAKITA may deny warranty coverage if your engine or a part has failed due to abuse, neglect, improper
maintenance or unapproved modications. You are responsible for presenting your engine to the nearest service dealer authorized by MAKITA when a problem exists.
If you have any questions regarding your warranty rights and responsibilities, you should contact the MAKITA Warranty service Department at 1-800-4-MAKITA (462-5482) for the information.
THINGS YOU SHOULD KNOW ABOUT THE EMISSION CONTROL SYSTEM WARRANTY:
MAINTENANCE AND REPAIRS
You are responsible for the proper maintenance of the engine. You should keep all receipts and maintenance records covering the performance of regular maintenance in the event questions arise. These receipts and maintenance records should be transferred to each subsequent owner of the engine. MAKITA reserves the right to deny warranty coverage if the engine has not been properly maintained. Warranty claims will not be denied, however, solely because of the lack of required maintenance or failure to keep maintenance records.
MAINTENANCE, REPLACEMENT OR REPAIR OF EMISSION CONTROL DEVICES AND SYSTEMS MAY BE PERFORMED BY ANY REPAIR ESTABLISHMENT OR INDIVIDUAL; HOWEVER, WARRANTY REPAIRS MUST BE PERFORMED BY A SERVICE DEALER AUTHORIZED BY MAKITA. THE USE OF PARTS THAT ARE NOT EQUIVALENT IN PERFORMANCE AND DURABILI­TY TO AUTHORIZED PARTS MAY IMPAIR THE EFFECTIVENESS OF THE EMISSION CONTROL SYSTEM AND MAY HAVE A BEARING ON THE OUTCOME OF A WARRANTY CLAIM.
If other than the parts authorized by MAKITA are used for maintenance replacements or for the repair of components affecting emis­sion control, you should assure yourself that such parts are warranted by their manufacturer to be equivalent to the parts authorized by MAKITA in their performance and durability.
HOW TO MAKE A CLAIM
All repair qualifying under this limited warranty must be performed by a service dealer authorized by MAKITA. In the event that any emission-related part is found to be defective during the warranty period, you shall notify MAKITA Warranty service Department at 1-800-4-MAKITA (462-5482) and you will be advised of the appropriate warranty service dealer or service providers where the warranty repair can be performed.
2
WARNING !
Careless or improper use of this product can cause serious or even fatal injury. Before operating a chain saw or other MAKITA products it is important that you read, fully understand and carefully follow the instructions outlined in this operator’s manual. Kickback may cause severe or fatal injury and is one of many potential dangers in operating a chain saw. Kickback and other safety related precauti­ons are described in detail within this operator’s manual. Additional operator’s manuals are available from www.makitausa.com and 1-800-4-MAKITA (462-5482) and MAKITA CANADA INC.,1950 Forbes Street, Whitby, Ontario, L1N 7B7, Canada, Telephone: (905) 571 22 00.
This product complies with: American National Standard Institute B 175.1-2000 chain saw safety standard. Canadian Standards Association Z62.1-03 chain saw safety standard. Z62.3-04 chain saw kickback standard.
Society of Automotive Engineers SAEJ 335-Jun 95 „Multiposition small
engine exhaust system re ignition
suppression”
The Emissions Compliance Period referred to on the emission Compliance label indicates the number of operat­ing hours for which the engine has been shown to meet federal emissions requirements. Category C= 50 hours, B= 125 hours, and A= 300 hours.
With the purchase of this chain saw you have chosen a German quality product. Important instructions for the assembly and operation of this saw are given in this manual. For your own safety, we ask you to read the acci­dent prevention instructions very carefully before putting your chain saw into operation, as incorrect handling can, despite all precautions, lead to accidents. With a little care and attention you will have good service and lasting
satisfaction from this rst-rate product.
EA3500F, EA4300F
Contents
Page
Delivery inventory .................................................... 4
Symbols ...................................................................4
Safety precautions ..............................................5-16
Denomination of components ................................17
Technical data........................................................18
Only for Models with fastening nuts on the sprocket guard
Mounting the guide bar and saw chain ........19-26
Tightening the saw chain ..................................
20
Checking the chain tension .............................. 21
Retightening the saw chain .............................. 21
Only for Models with QuickSet guide bar ..................
Mounting the guide bar and saw chain ............. 22
Tensioning the saw chain ................................. 23
Checking the chain tension .............................. 23
Retensioning the saw chain ..............................23
Models with quick tensioner on sprocket guard ..........
Mounting the guide bar and saw chain ............. 24
Tightening the saw chain ..................................
Checking the chain tension ..............................
Retensioning the saw chain ..............................
25
26
26
Chain brake ...........................................................26
Engaging the chain brake ......................................26
Fuel / Refuelling................................................27-28
Contents
Page
Chain lubrication ....................................................29
Starting the engine ................................................30
Stopping the engine............................................... 30
Checking the chain brake ...................................... 31
Working in winter ................................................... 31
Adjusting the carburetor ........................................32
Sharpening the saw chain ................................33-34
Cleaning the brake band and sprocket interior ...... 35
Cleaning the guide bar ..........................................35
Replacing the saw chain........................................ 36
Cleaning the air lter.............................................. 37
Replacing the spark plug ....................................... 38
Checking the mufer screws .................................38
Replacing the starter cable ....................................39
Replacing the return spring ...................................39
Mounting the fan housing ......................................39
Cleaning the cylinder area .....................................40
Replacing the fuel lter .......................................... 40
Replacing / cleaning the spark arrester screen ..... 40
Instructions for daily and periodic maintenance ....41
Service, spare parts and guarantee ......................42
Troubleshooting .....................................................43
Extract from the spare parts list ........................44-45
The EA3500F and EA4300F will be delivered in a protective cardboard box to prevent transport damage. Cardboard
is a basic raw material and is consequently reuseable or suitable for recycling (waste paper recycling).
3
Delivery inventory
1
4
5 6 7
32
1 Chain saw 2 Guide bar 3 Saw chain 4 Chain protection cover 5 Universal wrench 6 Wrench 7 Screw driver for carburetor adjustment 8 Operator’s and Safety Manual (not shown)
In case one of the parts listed should not be included in the delivery inventory, please consult your sales agent.
Symbols
You will notice the following symbols on the chain saw and in the Operator’s and Safety Manual:
Read Operator’s and Safety Manual and follow the warning- and safety
Caution, kickback!
precautions!
Particular care and caution!
Chain brake
Forbidden!
Fuel and oil mixture
Wear protective helmet, eye and ear protection!
Normal / Winter operation
Wear protective gloves!
Carburetor adjustment
No smoking!
Chain oil ll/oil pump
No open re!
Saw chain oil adjustment screw
Stop engine!
First aid
Start engine
Do not touch hot surfaces!
Combination switch Start/Stop (I/O), Choke
Recycling
Safety position
4
Further symbols see page 6.
Safety precautions for chain saw operators
Additional safety precautions
While operating the chain saw please observe the following rules:
a) Contact of the guide bar nose with any object should be avoided.
b) Tip contact may cause the guide bar to move suddenly upward and backward, which may cause serious or fatal injury.
c) Always operate the chain saw with both hands.
WARNING!
Read and follow all safety precautions in the operator’s manual. Failure to follow instructions could result in serious injury. It is recommended to lend the chain saw only to people who are expe­rienced in working with chain saws. Always hand over the Operator’s and Safety Manual.
WARNING!
This chain saw is capable of severe kickback that could result in serious injury to the operator. Do
not operate this chain saw unless you have ex­traordinary cutting needs and experience in and
special training for dealing with kickback. Chain
saws with signicantly reduced kickback potential
are available.
The following additional safety precautions must be observed by all users of chain saws:
1. Do not operate a chain saw when you are fatigued.
2. Use safety footwear; snug-tting clothing; protec
tive gloves; and eye, hearing, and head protection devices.
3. Use caution when handling fuel. Move the chain saw at least 10 feet (3 m) from the fueling point before starting the engine.
4. Do not allow other persons to be near the chain saw when starting or cutting with the chain saw. Keep bystanders and animals out of the work area.
5. Do not start cutting until you have a clear work area, secure footing, and a planned retreat path from the falling tree.
6. Keep all parts of your body away from the saw chain when the engine is running.
7. Before you start the engine, make sure that the saw chain is not contacting anything.
8. Carry the chain saw with the engine stopped, the
guide bar and saw chain to the rear, and the mufer
away from your body.
-
WARNING!
Kickback may occur when the nose or tip of the guide bar touches an object, or when the wood closes in and pinches the saw chain in the cut. This contact may abruptly stop the saw chain and in some cases may cause a lightning fast reverse reaction, kicking the guide bar up and back towards the user, or push the guide bar back towards the operator. Kickback may cause you to lose control of the saw.
As a chain saw user, you can take several steps to reduce the risk of a kickback and potential injury.
A. With a basic understanding of kickback, you
can reduce or eliminate the element of sur­prise. It is a sudden surprise that contributes to accidents.
B. Keep a good rm grip on the saw with both
hands, your right hand on the rear grip and your left hand on the tubular handle, when the
engine is running. Use a rm grip with thumbs and ngers encircling the chain saw handles. A rm grip can neutralize kickback and help you
maintain control of the saw. Don’t let go!
C. Make sure that the area in which you are cut
ting is free from obstructions. Do not let the nose of the guide bar contact the log, branch, or any other obstructions which could be hit while you are operating the saw.
D. Do not overreach or cut above shoulder
height.
E. Follow manufacturer’s sharpening and main-
tenance instructions for the saw chain.
F. Only use replacement bars and chains speci-
ed by the manufacturer or the equivalent.
9. Do not operate a chain saw that is damaged, is improperly adjusted, or is not completely and securely assembled. Be sure that the saw chain stops moving when the throttle control trigger is released.
10. Shut off the engine before setting it down.
11. Use extreme caution when cutting small size brush
and saplings because slender material may catch the saw chain and be whipped toward you or pull you off balance.
12. When cutting a limb that is under tension be alert for springback so that you will not be struck when
the tension on the wood bers is released.
13. Keep the handles dry, clean, and free of oil or fuel
mixture.
14. Operate the chain saw only in well-ventilated areas.
15. Do not operate a chain saw in a tree unless you
have been specically trained to do so.
16. All chain saw service, other than the items listed
-
in the operator’s manual maintenance instructions,
should be performed by MAKITA. (For example, if improper tools are used to remove the ywheel or if an improper tool is used to hold the ywheel
in order to remove the clutch structural damage to
the ywheel could occur and could subsequently cause the ywheel to burst.)
17. When transporting your chain saw, use the chain protection cover.
18. Low kickback bars and low kickback chains are designed to reduce the risk of kickback injury. Ask your MAKITA dealer about these devices.
5
max. CKA 45
O
max. CKA 40
O
C US
General Safety Precautions
XXX.YYY.ZZZ
XXX.YYY.ZZZ
The use of any chain saw may be hazardous. At full throttle chain speed can reach 45 mph (20 m/s). It is important that you read; fully understand and observe the following safety precautions and warnings. Read the Operator’s Manual and the safety instructions periodically.
Maximum Computed Kickback Angle (CKA)* without using the chain brake when using the recommended bar and chain combinations (In this example the CKA is 45°).
Ma ximumCo mputed Kickbac k An gle (CKA)* with using the chain brake when using the recommended bar and chain combinations (In this example the CKA is 40°).
WARNING !
Reactive forces, including kickback, can be dan­gerous. Careless or improper use of any chain saw may cause serious or fatal injury.
Have your MAKITA dealer show you how to operate your chain saw. Observe all applicable local safety regulations, standards and ordinances.
1
WARNING!
Minors should never be allowed to use a chain saw. Bystanders, especially children and animals should not be allowed in the area where a chain saw is
in use (g. 1).
Never let the saw run unattended. Store it in a locked place away from children. Fill the fuel tank to 7/8 th full (see storing the saw). Do not lend your chain saw without this Operator’s and Safety Manual. Be sure that anyone using your saw understands the information given.
Contact of the guide bar tip with any object should be avoided! Tip contact may cause the guide bar to move suddenly upward and backward, which may cause serious injury!
Always use two hands when operating the chain saw!
Reduced Kickback Bar and Chain combination that has been evaluated with the power head to achieve kickback protection (according to ANSI and CSA standards).
* The Computed Kickback Angle is a calculated value from energies measured on a test bench.It is not the angle of the guide bar moved upward in case of a KICKBACK.
The operator
Physical Condition
You must be in good physical condition and mental
health and not under the inuence of any substance (drugs, alcohol), which might impair vision, dexterity
or judgment.
2
Proper use of a chain saw involves
1. the operator
2. the saw
3. the use of the saw.
Discription of symbols used on chain saws:
CSA Standards Z62.1-03 Class 1A Z62.3-04
ANSI Standard B175.1-2000 SAE Standard SAE J335
6
WARNING !
Prolonged use of chain saws exposing the operator to vibrations may produce Whitenger disease (Ray-
naud’s phenomenon). This phenomenon reduces the hand’s ability to feel and regulate temperature, produces numbness and burning sensations and may cause nerve and circulation damage and tissue necrosis.
All MAKITA saws are therefore provided with an antivibration system which is essential for those using chain saws on a regular or sustained basis. Antivibration systems do not guarantee that you
will not sustain Whitenger disesase, however, they
reduce this danger considerably. Nevertheless, continual and regular users should observe their
hands and ngers and in case of any abnormal
symptoms, seek medical advice immediately.
Proper clothing
The saw
Clothing must be sturdy and snug-tting, but allow complete freedom of movement. Avoid loose-tting jackets, scarfs, neckties, jewelry, ared or cuffed pants,
or anything that could become entangled with the saw or brush. Wear overalls or jeans with a reinforced cutting
resistant insert (g. 3).
Protect your hands with gloves when handling saw and saw chain. Heavy-duty, nonslip gloves improve your grip and protect your hands.
Parts of the chain saw: illustrations and description of parts see page 17.
WARNING !
Never modify a chain saw in any way. Only attach-
ments supplied by MAKITA or expressly approved by MAKITA for use with the specic saw are au-
thorized.
WARNING !
Bow guide bars substantially increase the potential for kickback and severe or fatal injury due to the greater kickback zone of the bow design. Bow guide bars are not recommended for use on MAKITA chain saws nor are they approved by the ANSI B
175.1-2000 chain saw safety standard.
The use of the saw
Transporting the chain saw
3
Good footing is most important in chain saw work. Wear sturdy boots with nonslip soles. Steel-toed safety boots are recommended.
Proper eye protection is a must. Non-fogging, vented goggles and a face screen is recommended. Their use reduces the risk of eye and facial injury.
Wear an approved safety hard hat to protect your head. Chain saw noise may damage your hearing. Always wear noise protection equipment (ear plugs or ear muffs) to protect your hearing.
Continual and regular users should have their hearing checked regularly.
WARNING!
Always stop the engine before putting a chain saw down or carrying it. Carrying a chain saw with the
engine running is extremely dangerous. Accidental
acceleration of the engine can cause the chain to rotate.
Avoid touching the hot mufer.
4
By hand: When carrying your saw by hand, the engine must be stopped and the saw must be in the proper position. The chain protection cover should be over the chain and the guide bar must point backwards. When carrying your saw the bar should be behind
you (g. 4).
Wear protective helmet, eye and ear protection!
By vehicle: When transporting in a vehicle, keep
chain and bar covered with the chain guard. Properly secure your saw to prevent turnover, fuel spillage and damage to the saw. Make sure the saw in not
exposed to heat or sparks.
7
Chain saw operating instructions
For assembly follow the procedure in the appropriate section "Mounting Guide Bar and Chain" of this manual. MAKITA chain, guide bar and sprocket must match each other (see the appropriate section in this manual).
WARNING!
Proper tension of the chain is extremely impor­tant. In order to avoid false setting the tensioning procedure must be followed as described in this
manual. Always make sure the hexagonal nut(s)
for the sprocket guard is (are) tightened securely after tensioning the chain. Check chain tension once more after having tightened the nuts and thereafter at regular intervals (always before starting to work). If the chain becomes loose while cutting, shut off the engine and then tighten. Never try to tighten the chain while the engine is running!
Fueling
Your MAKITA saw uses on oil-gasoline mixture for fuel
(see chapter "Fuel" of this manual).
Wipe off any spilled fuel before starting your saw and check for leakage.
Check for fuel leakage while refueling and during opera­tion. If fuel or oil leakage is found, do not start or run
the engine until leak is xed and spilled fuel has been
wiped away. Clothing with fuel on it has to be changed immediately (this is a danger to your life!). Avoid skin contact with fuel. Never loosen or remove the cap of the fuel tank while the engine is running.
Starting
Do not drop start. This method is very dangerous be-
cause you may lose control of the saw (g. 6).
5
WARNING!
Gasoline is an extremely ammable fuel. Use ex­treme caution when handling gasoline or fuel mix. Do not smoke or bring any sparks or ame near the fuel (g. 5).
Fueling instructions
Fuel your chain saw in well ventilated areas or out­doors. Always shut off the engine and allow it to cool before refueling. Select bare ground for fueling and move the chain saw at least 10 feet (3 m) from fueling
spot before starting the engine (g. 5a).
6
6a
Place the chain saw on rm ground or other solid
surface in an open area. Maintain a good balance and secure footing. Place your right foot through the rear
handle opening and rmly grasp the front handle with your left hand (g. 6a).
Be absolutely sure that guide bar and chain are clear of you or all other obstructions and objects, including the ground, because when the engine starts in semi­throttle position, engine speed will be fast enough for the clutch to engage the sprocket and turn the chain which may cause a kickback. Never attempt to start the saw when the guide bar is in a cut or kerf.
When you pull the starter grip, don’t wrap the starter rope around your hands. Do not allow the grip to
10 feet
snap back, but guide the starter rope slowly back to permit the rope to rewind properly. Failure to follow
this procedure may result in injury to hand or ngers
and may damage the starter mechanism.
5a
8
Important adjustments
WARNING!
At correct idle speed, chain should not turn. For di­rections to adjust idle speed, see the appropriate section of this operator’s manual.
Do not use a saw with incorrect idle speed adjust­ment. Adjust the idle speed yourself according to the appropriate section of this manual.
Have your MAKITA dealer check your saw and make proper adjustments or repairs.
Wrap your ngers tightly around the handles, keeping the handles cradled between your thumb and foren­ger (g. 7). With your hands in this position, you can
best oppose and absorb the push, pull and kickback forces of your saw without having it slip out of your grip (see section of reactive forces). Make sure your chain saw handle and grip are in good condition and free of moisture, pitch, oil or grease.
Always start a cut with the chain running at full speed and the spike bar in contact with the wood.
Check the saw chain tension frequently, especially just after installing a new chain. New chains may stretch more during their initial use. A properly ad­justed saw chain can be pulled freely around the guide bar by hand without sagging. Always stop the engine and wear gloves when checking or ad­justing the chain tension.
Working conditions
Operate your chain saw only outdoors. Operate the saw under good visibility and daylight conditions only.
WARNING!
Take extreme care in wet and freezing weather (rain, snow, ice). Put off the work when the weather is windy, stormy or rainfall is heavy. Clear the area where you are working.
WARNING!
Avoid stumbling on obstacles such as stumps, roots or rocks and watch out for holes or ditches.
Be extremely cautious when working on slopes or
uneven ground. There is increased danger of slip­ping on freshly debarked logs.
WARNING!
Never use the saw with one hand. You cannot control reactive forces (see pages 10 to 12) and may lose control of the saw.
8
WARNING!
Do not operate your chain saw in semi-throttle position. Cutting in this position does not permit the operator proper control of the saw or chain speed.
WARNING!
Never come too close to a rotating chain with your hands or body.
Cutting instructions
Always hold the saw rmly with both hands when the
engine is running. Place your left hand on the tubular handle and your right hand on grip and throttle lever. Left-handers should follow these instructions too.
7
WARNING!
Do not cut any material other than wood or wooden objects.
Use your chain saw for cutting only. It is not de­signed for prying or shoveling away limbs, roots or other objects.
When sawing, make sure that the saw chain does not touch any foreign materials such as rocks, nails
and the like (g. 8). Such objects may be ung
off, damage the saw chain or cause the saw to kickback.
9
9
In order to keep control of your saw, always maintain
a rm foothold. Never work on a ladder, in a tree or on
any other insecure support. Never use the saw above
shoulder height (g. 9).
10
Position the chain saw in such a way that your body is clear of the cutting attachment whenever the engine
is running (g. 10).
Don’t put pressure on the saw when reaching the end of a cut. The pressure may cause the bar and rotating chain to pop out of the cut or kerf, go out of control and strike the operator or some other object. If the rotating chain strikes some other object a reactive force (see pages 11 to 13 ) may cause the chain to strike the operator.
Reactive forces during the cut, including kickback
WARNING!
Reactive forces, that may occur during any cut are kickback, pushback and pull-in. Reactive forces can be dangerous! In any chain saw, the powerful force used to cut wood can be reversed (and work against the operator).
If the rotating chain is suddenly stopped by con­tact with any solid object like a log or branch or is pinched, the reactive forces instantly occur. These reactive forces may result in loss of control which may, in turn, cause serious or fatal injury. An un­derstanding of the causes of these reactive forces may help you avoid loss of control.
The most common reactive forces are
- kickback,
- pushback,
- pull-in.
10
11
Kickback:
Kickback occurs when the upper quadrant of the bar nose contacts a solid object in the wood or is pinched
(g. 11). The reaction of the cutting force of the chain
causes a rotational force of the chain saw in the direc tion opposite to the chain movement, mainly in the plane
of the bar. This may ing the bar in an uncontrolled arc
towards the operator.
12
This reaction can occur in a fraction of a second and under some circumstances, cause the guide bar and chain to strike the operator with enough force to cause severe or fatal injury. It may also occur during limbing. It also occurs when the nose of the guide bar is pinched
unexpectedly, unintentionally contacts solid material in the wood (g.12) or is incorrectly used to begin a
plunge or boring cut.
The greater the force of the kickback reaction, the
more difcult it becomes for the operator to control
the saw.
Many factors inuence the occurence and force of the kickback reaction. The type of bar and saw chain you use is a factor in the force of the kickback reaction.
The speed of contact at which the cutter contacts the object.
Kickback force increase with the rate of impact.
The contact angle between the nose of the bar and the foreign object (g. 11).
Kickback is most pronounced in the upper quadrant of the bar nose.
MAKITA chain types are designed to reduce kickback forces.
The depth gauges:
Improper lowering of the depth gauges also increases the risk of a kickback.
Saw chain cutter sharpness:
13
To avoid kickback
The best protection from personal-injury that may result from kickback is to avoid kickback situations:
1. Hold the chain saw rmly with both hands and
maintain a secure grip.
2. Be aware of the location of the guide bar nose at
all times.
WARNING!
A dull improperly sharpened chain may increase the risk of kickback. Always cut with a properly sharpened chain.
Devices for reducing the risk of kickback injury
MAKITA have developed a special chain brake to reduce the risk of kickbacks.
This chain brake increases the safety factor on the job, e.g. when the saw suddenly bucks upwards the chain stops rotating within a fraction of a second. A
deection guard on the disengaging lever of the chain
brake and a scoop rear handle ensure that the opera­tor’s hands are fully protected at all times.
Kickback tendency increases as the radius or size of the guide bar nose increases. MAKITA have devel­oped guide bars with small nose radius, to reduce the kickback tendency.
WARNING!
No chain brake prevents kickback. These brakes are designed only to stop the chain, if activated. To ensure a proper operation of the chain brake, it must be properly maintained. Furthermore, there must be a sufcient distance between the opera­tor and the bar to ensure that the chain brake has
sufcient time to activate and stop the chain before
potential contact with the operator.
3. Never bring the nose of the guide bar in contact
with any object. Do not cut limbs with the nose of the guide bar. Be especially careful with small, tough limbs, small size brush and saplings which may easily catch the chain.
4. Don’t overreach.
5. Don’t cut above shoulder height.
6. Begin cutting and continue at full throttle.
7. Cut only one log at a time.
8. Use extreme caution when re-entering a previous
cut.
9. Do not attempt plunge cuts (see page 14) if you are
not experienced with these cutting techniques.
10. Be alert for shifting of the log or other forces that
may cause the cut to close and pinch the chain.
11. Maintain saw chain properly. Cut with a correct-
ly sharpened, properly tensioned chain at all times.
12. Stand to the side of the cutting path of the chain
saw.
11
Pushback:
To avoid pull-in
Pushback occurs when the chain on the top of the
bar is suddenly stopped when it is pinched, caught
or encounters a foreign object in the wood. The reac-
tion of the chain drives the saw straight back toward
the operator causing loss of saw control. Pushback
fre-quently occurs when the top of the bar is used for
cutting (g. 14).
14
To avoid pushback
1. Be alert to forces or situations that may cause material to pinch the top of the chain.
2. Do not cut more than one log at a time.
3. Do not twist the saw when withdrawing the bar
from a plunge cut or under buck cut (gures 25 to
27 and 33, pages 14 and 16), because the chain can pinch.
Pull-in:
Pull-in occurs when the chain on the bottom of the bar is suddenly stopped. The chain on the bottom of the bar stops when it is pinched, caught or encounters a
foreign object in the wood (see g. 15). The reaction of
the chain pulls the saw forward, causing the operator to lose control.
1. Always start a cut with the chain rotating at full speed and the spike bar in contact with the wood.
2. Pull-in may also be prevented by using plastic wedges to open the kerf or cut.
Cutting techniques
Felling
Felling is cutting down a tree.
Before felling a tree, consider carefully all conditions which may affect the direction of fall, including:
The intended direction of the fall. The neutral lean of the tree. Any unusually heavy limb structure. Surrounding trees and obstacles. The wind direction and speed.
WARNING!
Always observe the general condition of the tree. Look for decay and rot in the trunk. If it is rotted inside, it could snap and fall toward the operator while being cut. Also look for broken or dead branches which could vibrate loose and fall on the operator. When fell­ing on a slope, the operator should stand on the up-hill side.
Pull-in frequently occurs when the spike bar of the saw is not held securely against the tree or limb and when the chain is not rotating at full speed before it contacts the wood.
15
WARNING!
Use extreme caution when cutting small size brush
and saplings which may easily catch the chain and pull you off balance.
12
16
When felling in the vicinity of roads, railways and
power lines, etc., take extra precautions (see g.
16). Inform the police, utility company or railway authority before beginning to cut.
45°
1/10
1/5
11/
2
"
(4cm)
1
2
2
45°
= cutting down area
17
When felling, maintain a distance of at least 2 1/2 tree
lengths from the nearest person (see g. 17).
Note:
The noise of your engine may drown any warning call.
Felling instructions:
First cut
Second cut
20
If the tree has large buttress roots, cut into the largest
buttresses vertically rst (horizontally next) and remove (g. 20).
Direction of fall
21
18
First clear the tree base and work area from inter­fering limbs and brush and clean its lower portion an
axe (see g. 18).
45°
19
Then, establish a path of escape and remove all obsta­cles. This path should be opposite to the planned
direction of the fall of the tree and at a 45° angle (g.
19). An alternate path must also be selected. Place all tools and equipment a safe distance away from the tree, but not on the escape path.
Felling cut
Hinge
Felling notch
22
Felling notch
Hinge
23
Then, determine the placement of the felling notch
(g. 21). The felling notch when properly placed de-
termines the direction in which the tree will fall. It is made perpendicular to the line of fall and should be as close to the ground as possible. Cut the felling notch
to a depth of about one-fth to one-fourth of the trunk diameter (g. 22). It should be in no case higher than
it is deep. Make the felling notch very carefully.
13
1
2
3
Begin the felling cut slighty higher than the felling notch
and on the opposite side of the tree (g. 22). Then cut
horizontally through towards the felling notch. Apply the chain saw with its spikes directly behind the uncut
portion of wood and cut toward the notch (g. 23). Leave approximately 1/10 of the tree diameter uncut! This is the hinge (g. 23). Do not cut through the hinge
because you could lose control of the direction of the fall. Drive wedges into the felling cut where necessary to control the direction of the fall. Wedges should be of wood, light alloy or plastic - never of steel, which can cause kickback and damage to the chain.
Always keep to the side of the falling tree. When the tree starts to fall, shut off the engine, withdraw the bar and walk away on the pre-planned escape path. Watch out for falling limbs.
WARNING!
Be extremely careful with partially fallen trees which
are poorly supported.
Plunge-Cut Method
Timber having a diameter more than twice the length of the guide bar reauires the use of the plunge-cut method before making the felling cut. First, cut a large, wide notch. Make a plunge cut in the center of the notch. The plunge cut is made with the guide bar nose. Begin the plunge cut by applying the lower portion of the
guide bar nose to the tree at an angle (g. 25). Cut until
depth of the kerf is about the same as the width of the
guide bar (g. 26). Next, align the saw in the direction
When the tree hangs or for some other reason does not fall completely, set the saw aside and pull the tree down with a cable winch, block and tackle or tractor. If you try to cut it down with your saw, you may be injured.
Sectioning Method
WARNING!
Felling a tree that has a diameter greater than the length of the guide bar requires use of either the sectioning or plunge-cut method. These methods
are extremely dangerous because they involve
the use of the nose of the guide bar and can result in kickback. Only properly trained professionals should attempt these techniques.
25
in which the recess is to be cut. With the saw at full
throttle, insert the guide bar in the trunk (g. 27).
Enlarge the plunge cut as shown in illustration (g. 28)
26
24
For the sectioning method (g. 24) make the rst cut
with the guide bar fanning in toward the hinge. Then, using the bumper spike as a pivot, reposition the saw
for the next cut. Avoid repositioning the saw more than necessary. When repositioning for the next cut, keep
the guide bar fully engaged in the kerf to keep the felling cut straight. If the saw begins to pinch, insert a wedge to open the cut. On the last cut, do not cut the hinge.
14
27
28
1
2
3
29
Bucking
Bucking is cutting a log into sections.
WARNING!
There is an extreme danger of kickback at this point. Extra caution must be taken to maintain
control of the saw. To make the felling cut, follow
the sectioning method described previously (g.
29). If you are inexperienced with a chain saw
plunge-cutting should not be attempted. Seek the help of a professional.
Limbing
Limbing is removing the branches from a fallen tree.
WARNING!
There is an extreme danger of kickback during the
limbing operation. Do not work with the nose of the
bar. Be extremely cautious and avoid contacting
the log or other limbs with the nose of the guide bar. Do not stand on a log while limbing it - you may slip or the log may roll.
31
WARNING!
1. When bucking, do not stand on the log. Make sure the log will not roll down-hill. If on a slope,
stand on the up-hill side of the log (see g. 31).
Watch out for rolling logs.
WARNING!
2. Cut only one log at a time.
WARNING!
3. Shattered wood should be cut very carefully.
Sharp slivers of wood may be caught and ung
in the direction of the operator of the saw.
30
Start limbing by leaving the lower limbs to support
the log off the ground (g. 30). Always cut from
the top of the limb. Do not underbuck freely hang­ing limbs. A pinch may result or the limb may fall, causing loss of control. If a pinch occurs, stop the engine and remove the saw, by lifting the limb.
Be extremely cautious when cutting limbs under
tension. The limbs could spring back toward the operator and cause loss of control of the saw or injury to the operator.
WARNING!
32
WARNING!
4. When cutting small logs, use a sawhorse (g.
32). Never permit another person to hold the log. Never hold the log with your leg or foot.
15
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