Hitachi Koki CS 51EA User manual

Chain Saw
Model CS 51EA
Handling instructions
Note:
Before using this machine, carefully read through these HANDLING INSTRUCTIONS
to ensure efficient, safe operation. It is recommended that these INSTRUCTIONS be
kept readily available as an important reference when using this machine.
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MEANINGS OF SYMBOLS
NOTE: Some units do not carry them.
Symbols
WARNING
The following show symbols used for the machine. Be sure that you understand their meaning before use.
It is important that you read, fully understand and
observe the following safety precautions and
warnings. Careless or improper use of the unit may
cause serious or fatal injury.
Emergency stop
Read, understand and follow all warnings and
instructions in this manual and on the unit. Fuel and oil mixture
Always wear eye, head and ear protectors when using
this unit. Chain oil fi ll
Warning, kickback danger. Be careful of possible
sudden and accidental upward and/or backward
motion of the guide bar.
Carburetor adjustment -Idle speed
One-handed usage not permitted. While cutting, hold
saw fi rmly with both hands with thumb fi rmly locked
around front handle.
Carburetor adjustment -Low speed mixture
Chain brake Carburetor adjustment -High speed mixture
Choke Oil pump adjustment
On/Start Priming pump
Off/Stop Decompression valve
Contents
WHAT IS WHAT? .............................................................................. 3
WARNINGS AND SAFETY INSTRUCTIONS .................................. 3
SPECIFICATIONS ............................................................................ 5
ASSEMBLY PROCEDURES............................................................. 5
OPERATING PROCEDURES........................................................... 6
MAINTENANCE.............................................................................. 10
Parts breakdown
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WHAT IS WHAT?
1. Throttle lever: Device activated by the operatorʼsfi nger, for
controlling the engine speed.
2. Throttle lever lockout: Device that prevents the accidental
operation of the throttle lever until manually released.
3. Stop switch: Device for allowing the engine to be started or
stopped.
4. Oil tank cap: For closing the oil tank.
5. Recoil starter: Pull handle to start the engine.
6. Front handle: Support handle located at or towards the front of
the engine housing.
7. Fuel tank cap: For closing the fuel tank.
8. Choke lever: Device for enriching the fuel/air mixture in the
carburetor, to aid starting.
9. Priming pump; Device for supplying extra fuel, to aid starting.
10. Decompression valve: Device for reducing the compression
pressure to aid starting.
11. Guide bar: The part that supports and guides the saw chain.
12. Saw chain: Chain, serving as acutting tool.
13. Chain brake (Front hand guard): Device for stopping or locking
the chain.
14. Spiked bumper: Device for acting as apivot when in contact with
atree or log.
15. Chain catcher: Device for restraining the saw chain.
16. Guide bar cover: Device for covering the guide bar and saw
chain when the unit is not being used.
17. Combi box spanner: The tool for removing or installing aspark
plug and tensioning the saw chain.
18. Handling instructions: Included with unit. Read before operation
and keep for future reference to learn proper, safe techniques.
15
16 16
17
17 18
13
12
11
14
8
2
915
10
6
5
1
37
4
WARNINGS AND SAFETY INSTRUCTIONS
Operator safety
○Always wear asafety face shield or goggles.
○Gloves should be used when sharpening chain.
○Always wear safety protective equipment such as jacket,
trousers, gloves, helmet, boots with steel toe-caps and non-slip
soles, and eye, ear and leg protection equipment whenever you
use achain saw. For working in trees the safety boots must be
suitable for climbing techniques. Do not wear loose clothing,
jewelry, short pants, sandals or go barefoot.
Secure hair so it is above shoulder length.
○Do not operate this tool when you are tired, ill or under the
infl uence of alcohol, drugs or medication.
○Never let achild or inexperienced person operate the machine.
○Wear hearing protection. Pay attention to your surroundings.
Be aware of any bystanders who may be signaling aproblem.
Remove safety equipment immediately upon shutting offengine.
○Wear head protection.
○Never start or run the engine inside aclosed room or building.
Breathing exhaust fumes can kill.
○For respiratory protection, wear aprotection mask while emitting
the chain oil mist and dust from sawdust.
○Keep handles free of oil and fuel.
○Keep hands away from cutting equipment.
○Do not grab or hold the unit by the cutting equipment.
○When the unit turned off,make sure the cutting attachment has
stopped before the unit is set down.
○When operation is prolonged, take abreak from time to time
so that you may avoid possible Hand-Arm Vibration Syndrome
(HAVS) which is caused by vibration.
○The operator must obey the local regulations of cutting area.
WARNING
○Antivibration systems do not guarantee that you will not sustain
Hand-Arm Vibration Syndrome or carpal tunnel syndrome.
Therefore, continual end regular users should monitor closely
the condition of their hands and fi ngers. If any of the above
symptoms appear, seek medical advice immediately.
○Long or continuous exposure to high noise levels may cause
permanent hearing impairment. Always wear approved hearing
protection when operating aunit/machine.
○If you are using any medical electric/electronic devices such
as apacemaker, consult your physician as well as the device
manufacturer prior to operating any power equipment.
Unit/machine safety
○Inspect the entire unit/machine before each use. Replace
damaged parts. Check for fuel leaks and make sure all fasteners
are in place and securely tightened.
○Replace parts that are cracked, chipped or damaged in any way
before using the unit/machine.
○Make sure the side case is properly attached.
○Keep others away when making carburetor adjustments.
○Use only accessories as recommended for this unit/machine by
the manufacturer.
○Never let the chain strike any obstacle. If the chain makes
contact, the machine should be stopped and checked carefully.
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○Make sure the automatic oiler is working. Keep the oil tank fi lled
with clean oil. Never let chain run dry on the bar.
○All chain saw service, other than the items listed in the
operatorʼs/ ownerʼsmanual, should be performed by competent
chain-saw service personnel. (For example, if improper tools are
used to remove the fl ywheel or if an improper tool is used to hold
the fl ywheel in order to remove the clutch, structural damage
to the fl ywheel could occur and could subsequently cause the
fl ywheel to burst.)
WARNING
○Never modify the unit/machine in any way. Do not use your unit/
machine for any job except that for which it is intended.
○Never use chain saw without any safety equipment or that has
faulty safety equipment. It could result in serious personal injury.
○Using guide bar/chain other than recommended by the
manufacturer which are not approved, could result in ahigh risk
of personal accidents or injury.
Fuel safety
○Mix and pour fuel outdoors and where there are no sparks or
fl ames.
○Use acontainer approved for fuel.
○Do not smoke or allow smoking near fuel or the unit/machine or
while using the unit/machine.
○Wipe up all fuel spills before starting engine.
○Move at least 3maway from fueling site before starting engine.
○Stop engine and let it cool for afew minutes before removing fuel
tank cap.
○Empty the fuel tank before storing the unit/machine. It is
recommended that the fuel be emptied after each use. If fuel is
left in the tank, store so fuel will not leak.
○Store unit/machine and fuel in area where fuel vapors cannot
reach sparks or open fl ames from water heaters, electric motors
or switches, furnaces, etc.
WARNING
Fuel is easy to ignite or get explosion or inhale fumes, so that pay
special attention when handling or fi lling fuel.
Cutting safety
○Do not cut any material other than wood or wooden objects.
○For respiratory protection, wear an aerosol protection mask
when cutting the wood after insecticide has been applied.
○Keep others including children, animals, bystanders and helpers
outside the hazard zone. Stop the engine immediately if you are
approached.
○Hold the unit/machine fi rmly with the right hand on the rear
handle and the left hand on the front handle.
○Keep fi rm footing and balance. Do not over-reach.
○Keep all parts of your body away from the muffler and cutting
attachment when the engine is running.
○Keep Bar/Chain below waist level.
○Before felling atree, the operator must be accustomed to the
sawing techniques of the chain saw.
○Be sure to pre-plan asafe exit from afailing tree.
○While cutting, hold the unit/machine fi rmly with both hands with
thumb fi rmly locked around front handle, and stand with feet well
balanced and your body balanced.
○Stand to the side of the saw when cutting -never directly behind
it.
○Always keep the spiked bumper face to atree, because the
chain may suddenly be drawn into atree, if so equipped.
○When completing acut, be ready to hold up the units as it breaks
into clear, so it will not follow through and cut your legs, feet or
body, or contact an obstruction.
○Be alert against kickback (when saw kicks up and back at
operator). Never cut with the nose of the bar.
○When relocating to anew work area, be sure to shut offthe
machine and ensure that all cutting attachments are stopped.
○Never place the machine on the ground when running.
○Always ensure that the engine is shut offand any cutting
attachments have completely stopped before clearing debris or
removing grass from the cutting attachment.
○Always carry afi rst-aid kit when operating any power equipment.
○Never start or run the engine inside aclosed room or building
and/or near the infl ammable liquid. Breathing exhaust fumes
can kill.
Maintenance safety
○Maintain the unit/machine according to recommended
procedures.
○Disconnect the spark plug before performing maintenance
except for carburetor adjustments.
○Keep others away when making carburetor adjustments.
○Use only genuine HITACHI replacement parts as recommended
by the manufacturer.
CAUTION
Do not disassemble the recoil starter. You may get apossibility
of personal injury with recoil spring.
WARNING
Improper maintenance could result in serious engine damage or
in serious personal injury.
Transport and storage
○Carry the unit/machine by hand with the engine stopped and the
muffler away from your body.
○Allow the engine to cool, empty the fuel tank, and secure the
unit/machine before storing or transporting in avehicle.
○Empty the fuel tank before storing the unit/machine. It is
recommended that the fuel be emptied after each use. If fuel is
left in the tank, store so fuel will not leak.
○Store unit/machine out of the reach of children.
○Clean and maintain the unit carefully and store it in adry place.
○Make sure stop switch is offwhen transporting or storing.
○When transporting or storage, cover chain with guide bar cover.
If situations occur which are not covered in this manual, take care and
use common sense. Contact HITACHI dealer if you need assistance.
Pay special attention to statements preceded by the following words:
WARNING
Indicates astrong possibility of severe personal injury or loss of
life, if instructions are not followed.
CAUTION
Indicates apossibility of personal injury or equipment damage, if
instructions are not followed.
NOTE
Helpful information for correct function and use.
WARNING
KICKBACK DANGER (Fig. 1)
One of the most severe dangers when working with achain saw is
the possibility of kickback. Kickback may occur when the upper tip
of the guide bar touches an object, or when the wood closes in and
pinches the saw chain in the cut. Tip contact in some cases may
cause alightning fast reverse reaction, kicking the guide bar up and
back toward you. Pinching the saw chain along the top of the guide
bar may also push the guide bar rapidly back towards you. Either of
these reactions may cause you to lose control of the saw which could
result in serious personal injury. Even though your saw has safety
built into its design, you should not rely on these safety features
exclusively. Know where your bar tip is at all times. Kickback does
occur if you allow the kickback zone (1) of the bar to touch an object.
Do not use that area. Kickback from pinching is caused by acut
closing and pinching the upper side of the guide bar. Study your cut
and make sure it will open as you cut through. Maintain control when
the engine is running by always keeping afi rm grip on the saw with
your right hand on the rear handle, your left hand on the front handle
and your thumbs and fi ngers encircling the handles. Always hold the
saw with both hands during operation and cut at high engine speed.
Follow manufacturer's sharpening and maintenance instructions
for the saw chain. The lack of this maintenance may increase the
possibility of kickback.
1
Fig. 1
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SPECIFICATIONS
○Code “CS” of model name means “Chain saw”
Model CS51EA (40S) CS51EA (45S) CS51EA (50S)
Type of equipment Chain saw, portable
Engine Size (cm3)50.1
Spark Plug NGK BPMR-7A
Fuel Tank Capacity (cm3)530
Chain Oil Tank Capacity (cm3)270
Dry Weight (kg)
(Without guide bar and chain) 5.1
Chain pitch (mm) 8.26
Chain gauge (mm) 1.27
Sound pressure level LpA (dB (A)) by ISO 22868
Equivalent
Uncertainty
104
1
Sound power level LwA (dB (A)) by ISO 22868
Measured
Uncertainty
Sound power level LwA (dB (A)) by 2000/14/EC
Measured
Guaranteed
113
2
114
117
Vibration level (m/s2)by ISO 22867
Front handle
Rear handle
Uncertainty
3.3
2.7
0.8
3.3
2.7
0.8
3.3
2.7
0.8
Guide bar length (mm) 400 450 500
Type of chain 95VPX
(Oregon)
20BPX
(Oregon)
Max. engine power
by ISO 7293 (kW) 2.5
Max. engine speed (min-1)13500
Idle engine speed (min-1) 3000
Specifi cfuel consumption at maximum engine
power (g/kWh) 439
Max. chain speed (m/sec) 26.0
Sprocket (number of teeth) 7
NOTE: Equivalent noise level/vibration levels are calculated as the time-weighted energy total for noise/vibration levels under various
working conditions with the following time distribution: 1/3 idle, 1/3 full, 1/3 racing speed.
*All data subject to change without notice.
ASSEMBLY PROCEDURES
WARNING
Never try to start engine without side case, bar and chain
securely fastened.
1. Pull the front hand guard (2) toward the front handle to check that
the chain brake is disengaged. (Fig. 2)
2
Fig. 2
2. Remove guide bar clamp nuts (3). Remove the side case (4).
(Fig. 3)
3
4
Fig. 3
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CAUTION
PROPER TENSION IS EXTREMELY IMPORTANT
8. Raise the bar end and securely tighten the guide bar clamp nuts
with the combi box spanner. (Fig. 7)
9. Anew chain will stretch so adjust the chain after afew cuts and
watch chain tension carefully for the fi rst half hour of cutting.
NOTE
Check the chain tension frequently for optimum performance
and durability.
CAUTION
○When the chain is excessively tightened, the bar and chain will
be damaged rapidly. Conversely, when the chain is excessively
loosened, it may get out of the groove in the bar.
○Always wear gloves when touching the chain.
WARNING
During operation, hold chain saw fi rmly with both hands. Asingle
hand operation may cause serious injury.
OPERATING PROCEDURES
Fuel (Fig. 8)
Fig. 8
WARNING
○The chain saw is equipped with atwo-stroke engine. Always
run the engine on fuel, which is mixed with oil. Provide good
ventilation, when fueling or handling fuel.
○Fuel contains highly fl ammable and it is possible to get the
serious personal injury when inhaling or spilling on your body.
Always pay attention when handling fuel. Always have good
ventilation when handling fuel inside building.
Fuel
○Always use branded 89 octane unleaded gasoline.
○Use genuine two-cycle oil or use amix between 25:1 to 50:1,
please consult the oil bottle for the ratio or HITACHI dealer.
○If genuine oil is not available, use an anti-oxidant added quality
oil expressly labeled for air-cooled 2-cycle engine use (JASO
FC GRADE OIL or ISO EGC GRADE). Do not use BIA or TCW
(2-stroke water-cooling type) mixed oil.
○Never use multi-grade oil (10 W/30) or waste oil.
○Always mix fuel and oil in aseparate clean container.
Always start by fi lling half the amount of gasoline, which is to be
used.
Then add the whole amount of oil. Mix (shake) the fuel mixture. Add
the remaining amount of gasoline.
Mix (shake) the fuel-mix thoroughly before fi lling the fuel tank.
Fueling
WARNING (Fig. 9)
○Always shut offthe engine before refueling.
○Slowly open the fuel tank (15), when fi lling up with fuel, so that
possible overpressure disappears.
○Tighten the fuel cap carefully, after fueling.
○Always move the unit at least 3mfrom the fueling area before
starting.
○Always wash any spilled fuel from clothing immediately with
soap.
○Be sure to check any fuel leaking after refueling.
Before fueling, clean the tank cap area carefully, to ensure that no
dirt falls into the tank. Make sure that the fuel is well mixed by shaking
the container, before fueling.
3. Install the guide bar (5) onto the bolts (6), then push it toward the
sprocket (7) as far as it will go.
69
10
8
11
5
7
4
Fig. 4
4. Confi rm the direction of saw chain (12) is correct as in the fi gure,
and align the chain on the sprocket. (Fig. 5)
12
Fig. 5
5. Guide the chain drive links into the bar groove all around the bar.
6. Install the side case (4) onto the bolts (6).
Make sure that the boss of chain tension adjust bolt (8) fi ts into
the hole (9) of the bar. (Fig. 4)
The brake lever (11) of the side case must fi tthe groove (10) on
the side of the front hand guard.
Then tighten the guide bar clamp nuts (3) by hand that allows the
guide bar end to move up and down easily.
( Fig. 3 )
7. Raise the bar end, and tighten the chain (12) by turning the
tension adjustment bolt (13) clockwise. To check proper tension,
lightly lift up the center of chain and there should be about 0.5
–1.0 mm clearance (14) between bar and edge of drive link.
(Fig. 6, 7)
12
14
13
0.5 –1mm
Fig. 6
Fig. 7
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15
16
Fig. 9
Chain oil (Fig. 9)
Fill up with chain oil (16). Always use good quality chain oil. When the
engine is running, the chain oil is automatically discharged.
NOTE
When pouring fuel (15) or chain oil (16) into the tank, place the
unit with cap side up. (Fig. 9)
ADJUSTMENT OF CHAIN OIL SUPPLY
The chain oil quantity discharged through the lubrication system
is adjusted to the maximum in the factory. Adjust the quantity in
accordance with the operating condition.
Turn the adjusting screw (17) counterclockwise to increase the
quantity and turn it clockwise to decrease the quantity. (Fig. 10)
17
Fig. 10
Chain brake operation (Fig. 2, 11)
Chain brake is designed to activate in an emergency such as kick-
back action.
Application of brake is made by moving the front hand guard towards
the bar. During the chain brake operation, even if the throttle lever
is pulled, the engine speed does not increase and the chain does
not turn. To release the brake, pull the front hand guard toward the
front handle.
If the engine keeps rotating at high speed with the brake engaged,
the clutch will overheat causing trouble.
When the brake engages during operation, immediately release the
throttle lever to slow down the engine.
How to confirm the activation of the chain brake
1) Turn offthe engine.
2) Holding the chain saw horizontally, release your hand from the
front handle, hit the tip of the guide bar to astump or apiece
of wood, and confi rm brake operation. Operating level varies by
bar size.
In case the brake is not effective, ask our dealer for inspection and
repairs.
Starting (Fig. 11-16)
CAUTION
Before starting, make sure chain brake is engaged and that the
bar/chain does not touch anything. (Fig. 11)
2
Fig. 11
1. Set ignition switch (18) to ON position. (Fig. 12)
18
Fig. 12
*Push priming pump (20) several times so that fuel fl ows through
bulb into carburetor. (Fig. 13)
19
20
Fig. 13
2. Pull the choke lever (19) to choked position (Fig. 13).
This will automatically lock to the half-throttle.
3. Push the decompression valve (21).
The valve (21) will automatically return to the original position once
the engine has started. (Fig. 14).
21
Fig. 14
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4. Pull recoil starter briskly, taking care to keep the handle in your
grasp and not allowing it to snap back. (Fig. 15)
Fig. 15
5. When you hear fi rst ignition, return the choke lever (19) all the
way in. (Fig. 13)
6. Push the decompression valve.
7. Pull recoil starter briskly again in the aforementioned manner.
(Fig. 15)
NOTE
If engine does not start, repeat procedures from 2to 7.
8. As soon as engine start, pull throttle lever (23) full once with
throttle lever lockout (22) and release immediately. (Fig. 16)
Then half-throttle is disengaged.
Pull the front hand guard (2) toward the front handle to disengage
the chain brake.
Allow the engine about 2-3 minutes to warm up before subjecting
it to any load.
Do not run the engine at high speed without the load to avoid
shortening the life of the engine.
23
22
Fig. 16
WARNING
Do not carry the machine with the engine running.
Stopping (Fig. 17)
Decrease engine speed, and push ignition switch (18) to stop
position.
18
Fig. 17
WARNING
○Do not overreach or cut above shoulder height.
○Use extra caution when felling, and do not use the saw in anose-
high position or above shoulder height.
CHAIN CATCHER
The chain catcher is located on the power head just below the chain
to further prevent the possibility of abroken chain striking the chain
saw user.
WARNING
Do not stand in-line with chain when cutting.
BASIC TECHNIQUES FOR MAKING FELLING, LIMBING AND
BUCKING CUTS
The intention of the following information is to provide you with the
general introduction to wood cutting techniques.
WARNING
○This information does not cover all specifi csituations, which
may depend on differences in terrain, vegetation, kind of wood,
form and size of trees, etc. Consult your servicing dealer,
forestry agent or local forestry schools for advice on specifi c
woodcutting problems in your area. This will make your work
more efficient and safer.
○Avoid cutting in adverse weather conditions, such as dense fog,
heavy rain, bitter cold, high winds, etc.
Adverse weather is often tiring to work in and creates potentially
dangerous conditions such as slippery ground.
High winds may force the tree to fall in an unexpected direction
causing property damage or personal injury.
CAUTION
Never use achain saw to pry or for any purpose for which it is not
intended.
WARNING
○Avoid stumbling on obstacles such as stumps, roots, rocks,
branches and fallen trees. Watch out for holes and ditches. Be
extremely cautious when working on slopes or uneven ground.
Shut offthe engine when moving from one work place to another.
Always cut at wide open throttle. Aslow moving chain can easily
catch and force the saw to jerk.
○Never use the saw with only one hand.
You cannot control the saw properly and you may lose control
and injure yourself severely.
Keep the saw body close to your body to improve control and
reduce strain.
When cutting with the bottom part of the chain the reactive force
will pull the saw away from you towards the wood you are cutting.
The saw will control the feeding speed and sawdust will be
directed towards you. (Fig. 18)
Fig. 18
○When cutting with the upper part of the chain the reactive force
will push the saw towards you and away from the wood you are
cutting. (Fig. 19)
Fig. 19
○There is arisk of kickback if the saw is pushed far enough so that
you begin to cut with the nose of the bar.
The safest cutting method is to cut with the bottom part of the
chain. Sawing with the upper part makes it much more difficult to
control the saw and increases the risk of kickback.
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○In case the chain locked, immediately release the throttle lever.
If the throttle lever keeps rotating at high speed with the chain
locked, the clutch will overheat causing trouble.
NOTE
Always keep the spiked bumper face to atree, because the
chain may suddenly be drawn into atree.
FELLING
Felling is more than cutting down atree. You must also bring it down
as near to an intended place as possible without damaging the tree
or anything else.
Before felling atree, carefully consider all conditions which may
effect the intended direction, such as:
Angle of the tree. Shape of the crown. Snow load on the crown.
Wind conditions. Obstacles within tree range (e.g., other trees,
power lines, roads, buildings, etc.).
WARNING
○Always observe the general conditions of the tree. Look for
decay and rot in the trunk which will make it more likely to snap
and start to fall before you expect it.
○Look for dry branches, which may break and hit you when you
are working.
Always keep animals and people at least twice the tree length
away while felling. Clear away shrubs and branches from around
the tree.
Prepare apath of retreat away from the felling direction.
BASIC RULES FOR FELLING TREES
Normally the felling consists of two main cutting operations, notching
and making the felling cut. Start making the upper notch cut on the
side of the tree facing the feeling direction. Look through the kerf as
you saw the lower cut so you do not saw too deep into the trunk. The
notch should be deep enough to create ahinge of sufficient width
and strength. The notch opening should be wide enough to direct
the fall of the tree as long as possible. Saw the felling cut from the
other side of the tree between one and two inches (3–5 cm) above
the edge of the notch. (Fig. 20)
24
25
26
27
Fig. 20
24. Felling direction
25. 45° minimum notch opening
26. Hinge
27. Felling cut
Never saw completely through the trunk. Always leave ahinge.
The hinge guides the tree. If the trunk is completely cut through, you
lose control over the felling direction.
Insert awedge or afelling lever in the cut well before the tree
becomes unstable and starts to move. This will prevent the guide
bar from binding in the felling cut if you have misjudged the falling
direction. Make sure no people have come into the range of the
falling tree before you push it over.
FELLING CUT, TRUNK DIAMETER MORE THAN TWICE GUIDE
BAR LENGTH
Cut alarge, wide notch. Then cut arecess into the center of the
notch. Always leave ahinge on both sides of the center cut. (Fig. 21)
Fig. 21
Complete the felling cut by sawing around the trunk as in the Fig. 22.
Fig. 22
WARNING
These methods are extremely dangerous because they involve
the use of the nose of guide bar and can result in kickback.
Only properly trained professionals should attempt these
techniques.
LIMBING
Limbing is removing the branches from afeller tree.
WARNING
Amajority of kickback accidents occur during Iimbing.
Do not use the nose of the guide bar. Be extremely cautious and
avoid contacting the log, other limbs or objects with the nose
of the guide bar. Be extremely cautious of limbs under tension.
They can spring back towards you and cause loss of control
resulting in injury. (Fig. 23)
Fig. 23
Stand on the left side of the trunk. Maintain asecure footing and
rest the saw on the trunk. Hold the saw close to you so that you are
in full control of it. Keep well away from the chain. Move only when
the trunk is between you and the chain. Watch out for spring back of
limbs under tension.
LIMBING THICK BRANCHES
When limbing thick branches, the guide bar may get pinched easily.
Branches under tension often snap up, so cut troublesome branches
in small steps. Apply the same principles as for cross cutting. Think
ahead and be aware of the possible consequences of all your
actions.
CROSS CUTTING/BUCKING
Before starting to cut through the log, try to imagine what is going to
happen. Look out for stresses in the log and cut through it in such a
manner that the guide bar will not get pinched.
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English
CROSS CUTTING LOGS, PRESSURE ON TOP
Take afi rm stance. Begin with an upper cut. Do not cut too deeply,
about 1/3 of the log diameter is enough. Finish with abottom cut.
The saw cuts should meet. (Fig. 24)
30
28
31
32
29
33
Fig. 24
28. Relieving cut
29. Cross cut
30. Pressure on top
31. Pressure side
32. Tension side
33. Relative depth of saw cuts
THICK LOG, LARGER THAN GUIDE BAR LENGTH
Begin by cutting on the opposite side of the log. Pull the saw towards
you, followed by previous procedure. (Fig. 25)
Fig. 25
If the log is lying on the ground make aboring cut to avoid cutting into
the ground. Finish with abottom cut. (Fig. 26)
Fig. 26
WARNING
KICKBACK DANGER
Do not attempt aboring cut if you are not properly trained. A
boring cut involves the use of the nose of the guide bar and can
result in kickback.
CROSS CUTTING LOGS, PRESSURE ON BOTTOM
Take afi rm stance. Begin with abottom cut. The depth of the cut
should be about 1/3 of the log diameter.
Finish with an upper cut. The saw cuts should meet. (Fig. 27)
36
35
37
38
34
39
Fig. 27
34. Relieving cut
35. Cross cut
36. Pressure on bottom
37. Tension side
38. Pressure side
39. Relative depth of saw cuts
THICK LOG, LARGER THAN GUIDE BAR LENGTH
Begin by cutting on the opposite side of the log. Pull the saw towards
you, followed by previous procedure. Make aboring cut if the log is
close to the ground. Finish with atop cut. (Fig. 28)
Fig. 28
WARNING
KICKBACK DANGER
Do not attempt aboring cut if you are not properly trained. A
boring cut involves the use of the nose of the guide bar and can
result in kickback. (Fig. 29)
Fig. 29
IF THE SAW GETS STUCK
Stop the engine. Raise the log or change its position, using athick
branch or pole as alever. Do not try to pull the saw free. If you do,
you can deform the handle or be injured by the saw chain if the saw
is suddenly released.
MAINTENANCE
MAINTENANCE, REPLACEMENT OR REPAIR OF THE EMISSION
CONTROL DEVICES AND SYSTEM MAY BE PERFORMED BY ANY
NON-ROAD ENGINE REPAIR ESTABLISHMENT OR INDIVIDUAL.
Carburetor adjustment (Fig. 30)
Fig. 30
In the carburetor, fuel is mixed with air. When the engine is test run at
the factory, the carburetor is adjusted. Afurther adjustment may be
required, according to climate and altitude. The carburetor has one
adjustment possibility:
T=Idle speed adjustment screw.
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Idle speed adjustment (T)
Check that the air filter is clean. When the idle speed is correct, the
cutting attachment will not rotate. If adjustment is required, close
(clockwise) the T-screw, with the engine running, until the cutting
attachment starts to rotate. Open (counter-clockwise) the screw
until the cutting attachment stops. You have reached the correct idle
speed when the engine runs smoothly in all positions well below the
rpm when the cutting attachment starts to rotate.
If the cutting attachment still rotates after idle speed adjustment,
contact HITACHI dealer.
WARNING
When the engine is idling the cutting attachment must under no
circumstances rotate.
NOTE
Do not touch the High speed adjustment (H) and the Low speed
adjustment (L).
Those are only for HITACHI dealer.
If you rotate them, It will cause a serious damage to the machine.
Air filter (Fig. 31)
The air filter (40) must be cleaned from dust and dirt in order to avoid:
○Carburetor malfunctions.
○Starting problems.
○Engine power reduction.
○Unnecessary wear on the engine parts.
○Abnormal fuel consumption.
Clean the air filter daily or more often if working in exceptionally
dusty areas.
Remove the air filter cover (41) and the filter (40).
Rinse them in warm soap suds. Check that the filter is dry before
reassembly. An air filter that has been used for some time cannot be
cleaned completely. Therefore, it must regularly be replaced with a
new one. A damaged filter must always be replaced.
40
41
Fig. 31
Spark plug (Fig. 32)
The spark plug condition is influenced by:
○An incorrect carburetor setting.
○Wrong fuel mixture (too much oil in the gasoline)
○A dirty air filter.
○Hard running conditions (such as cold weather).
These factors cause deposits on the spark plug electrodes, which
may result in malfunction and starting difficulties. If the engine is
low on power, difficult to start or runs poorly at idling speed, always
check the spark plug first. If the spark plug is dirty, clean it and check
the electrode gap. Readjust if necessary. The correct gap is 0.6 mm.
The spark plug should be replaced after about 100 operation hours
or earlier if the electrodes are badly eroded.
Fig. 32
NOTE
In some areas, local law requires using a resistor spark plug
to suppress ignition signals. If this machine was originally
equipped with resistor spark plug, use same type of spark plug
for replacement.
Oiler port (Fig. 33)
Clean the chain oiler port (42) whenever possible.
42
Fig. 33
Guide bar (Fig. 34)
Before using the machine, clean the groove and oiler port (43) in the
bar with the special gauge offered as an optional accessory.
43
Fig. 34
Side case (Fig. 35)
Always keep the side case and drive area clean of saw dust and
debris. Periodically apply oil or grease to this area to protect from
corrosion as some trees contain high levels of acid.
Fig. 35
Fuel filter (Fig. 36)
Remove the fuel filter from the fuel tank and thoroughly wash it in
solvent. After that, push the filter into the tank completely.
Fig. 36
NOTE
If the filter is hard due to dust and dirt, replace it.
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Chain oil filter (Fig. 37)
Remove the oil fi lter and thoroughly wash it in solvent.
Fig. 37
Cleaning the cylinder fins (Fig. 38)
When wood chips are caught between cylinder fi ns (44), the engine
may overheat, resulting in lower output. To avoid this, always keep
cylinder fi ns and fan case clean.
44
Fig. 38
Icing protection system (Fig. 39, 40)
This system is to protect carburetor from icing when the unit is
operated in winter time.
1. When you need icing system work, remove air fi lter cover (41).
Pull out the shutter (45) from inside the air fi lter cover and
reinstall it in winter time position by turning half-way. (Fig. 39)
This will allow heated air to fl ow from cylinder side to carburetor
cabin through the opening (46).
NOTE
When winter time has been over and carburetor will not suffer from
icing, make sure that the shutter is reinstalled in ordinary position
(Fig. 40).
45 46
41
Fig. 39
45
41
Fig. 40
For long-term storage
Drain all fuel from the fuel tank. Start and let engine run until it stops.
Repair any damage which has resulted from use. Clean the unit with
aclean rag, or the use of high pressure air hose. Put afew drops of
two-cycle engine oil into the cylinder through the spark plug hole,
and spin the engine over several times to distribute oil.
Cover the unit and store it in adry area.
CHAIN SHARPENING
Parts of acutter (Fig. 41, 42)
48 47
49
50
51 52 53 54
55
Fig. 41
56 57
58
59
Fig. 42
WARNING
○Gloves should be used when sharpening chain.
○Be sure to round offthe front edge to reduce the chance of
kickback or tie-strap breakage.
47. Top plate
48. Working corner
49. Side plate
50. Gullet
51. Heel
52. Chassis
53 Rivet hole
54. Toe
55. Depth gauge
56. Correct angle on top plate (degree of angle depends on chain
type)
57. Slightly protruding “hook” or point (curve on non-chisel chain)
58. Top of depth gauge at correct height below top plate
59. Front of depth gauge rounded off
LOWERING DEPTH GAUGES WITH AFILE
1) If you sharpen your cutters with afi le holder, check and lower the
depth.
2) Check depth gauges every third sharpening.
3) Place depth gauge tool on cutter. If depth gauge projects, fi le
it level with the top of the tool. Always fi le from the inside of the
chain toward an outside cutter. (Fig. 43)
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Fig. 43
4) Round offfront corner to maintain original shape of depth gauge
after using depth gauge tool. Always follow the recommended
depth gauge setting found in the maintenance or operator
manual for your saw. (Fig. 44)
Fig. 44
GENERAL INSTRUCTIONS FOR FILING CUTTERS
File (60) cutter on one side of the chain from the inside out. File on
forward stroke only. (Fig. 45)
60
60 60
Fig. 45
5) Keep all cutters the same length. (Fig. 46)
61
Fig. 46
6) File enough to remove any damage to cutting edges (side plate
(62) and top plate (63)) of cutter. (Fig. 47)
62 63
Fig. 47
NOTE
Do not fi le or alter the tops of bumper drive links (61). (Fig. 46)
7SHARPENING ANGLES FOR SHARPENING SAW CHAIN
1. Part Number 95VPX/20BPX
2. Pitch 0.325”
3. Depth Gauge Setting 0.025"
85° 4. Side Plate Filing Angle 85°
5. Top Plate Angle 30°
100° 6. File Guide Angle 100°
Maintenance schedule
Below you will fi nd some general maintenance instructions. For
further information please contact HITACHI dealer.
Daily maintenance
○Clean the exterior of the unit.
○Clean the chain oil fi lter port.
○Clean the groove and oil fi lter port in the guide bar.
○Clean the side case of saw dust.
○Check that the saw chain is sharp.
○Check that the bar nuts are sufficiently tightened.
○Make sure that the chain transport guard is undamaged and that
it can be securely fi tted.
○Check that nuts and screws are sufficiently tightened.
Especially inspect the bolt of muffler and ensure that they are
properly tightened before starting engine. Should any of the
bolts be loose, retighten them immediately. Failure to do so
could result in serious hazard.
○Check the tip of the guide bar. Please exchange it for the new
one when it is worn out.
○Check the band of chain brake. Please exchange it for the new
one when it is worn out.
○Clean the air fi lter.
Weekly maintenance
○Check the recoil starter, especially cord.
○Clean the exterior of the spark plug.
○Remove the spark plug and check the electrode gap. Adjust it to
0.6 mm or change the spark plug.
○Clean the cooling fi ns on the cylinder and check that the air
intake at the recoil starter is not clogged.
Monthly maintenance
○Rinse the fuel tank with gasoline, and clean fuel fi lter.
○Clean chain oil fi lter.
○Clean the exterior of the carburetor and the space around it.
○Clean the fan and the space around it.
NOTE
When ordering the parts to your nearest dealer, please use the
item numbers showing on the parts breakdown section in this
instruction.
BAR NO. LENGTH-TYPE CHAIN NO.
MODEL NO.
OREGON
160 MLBK 041
180 MLBK 041
200 PXBK 041
16”
18”
20”
95VPX-66
95VPX-72
20BPX-78
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14
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15
ITEM
NO. PART NAME Q’TY
1 START LABEL
1
2 CLEANER COVER (C51) 1
3 SHUTTER PLATE 1
4 COVER SET BOLT 7
5 CYLINDER COVER (C51) 1
6 CLEANER KNOB 1
7 KNOB PACKING 1
8 CLEANER ELEMENT (B) 1
9 CLEANER ELEMENT (A) 1
10 NUT M6 3
11 BOLT WASHER M6 1
12 SPRING HOLDER 1
13 HEX. SOCKET HD. BOLT
(W/FLANGE) M6
× 20 1
14 ANTIVIBRATION SPRING 1
15 DAMPER SET BOLT 3
16 SEAL LOCK SCREW M4
× 10 18
17 SCAVENGING COVER (B) 1
18 COVER PACKING (C51) 2
19 EXHAUST PIPE (C51) 1
20 MUFFLER GAUZE (C51) 1
21 TAPPING SCREW
(W/FLANGE) D5
× 25 2
22 FRONT HANDLE 1
23 TAPPING SCREW
(W/FLANGE) D5
× 20 2
24 HEX. SOCKET HD. BOLT
M4 × 10 5
25 BOLT WASHER M4 5
26 MUFFLER PROTECTOR 1
27 MUFFLER PROTECTOR
PACKING 1
28 MACHINE SCREW M4
× 16 3
29 OIL PIPE (CS40) 1
30 OIL PUMP 1
31 CLIP 4
32 SEAL LOCK HEX. SOCKET
HD. BOLT M5
× 30 4
33 SEA LOCK SCREW M5 × 12 3
34 SPIKE 1
35 SEAL LOCK HEX. SOCKET
HD. BOLT M5
× 45 2
36 MUFFLER CAP 2
37 HEX. SOCKET HD. BOLT
M6
× 20 6
38 HEX. SOCKET HD. BOLT
M5 × 12 5
39 MUFFLER (C51) 1
40 MUFFLER PACKING (C51) 1
41 GROMMET 2
42 FUEL PIPE 2.5
× 4 × 90 1
43 PRIMING PUMP COMP. 1
44 DECOMP. 1
45 SPARK PLUG BPMR7A 1
46 INTAKE PACKING (C51) 1
47 INTAKE (C51) 1
48 CAB. INSULATOR RUBBER 1
49 CARBURETOR INSULATOR
(C51) 1
50 FUEL PIPE 1
51 CARBURETOR ASS'Y 1
52 SCREW 1
53 PUMP GASKET 1
54 PUMP DIAPHRAGM 1
ITEM
NO. PART NAME Q’TY
55 INLET SCREEN 1
56 NEEDLE VALVE 1
57 VALVE SPRING 1
58 DIAPHRAGM
PACKING-METERING 1
59 METERING DIAPHRAGM 1
60 DIAPHRAGM
COVER-METERING 1
61 IDLE ADJUST SPRING 1
62 IDLE ADJUST SCREW 1
63 HINGE PIN SET SCREW 1
64 CONTROL LEVER 1
65 HINGE PIN 1
66 SET SCREW 1
67 FUEL PIPE 1
68 WASHER 55
69 HEX. SOCKET HD. BOLT
M5
× 45 2
70 CLEANER SUPPORT (C51) 1
71 FUEL PIPE 1
72 CYLINDER 1
73 SCAVENGING COVER (A) 1
74 CYLINDER PACKING (C51) 1
75 PISTON RING 2
76 PISTON (44) M1
77 CIR CLIP 2
78 PISTON PIN COLLAR (C51) 2
79 ENGINE CASE (B) 1
80 OIL SEAL 2
81 BALL BEARING 6202C3 2
82 CRANK SHAFT 1
83 CRANK CASE PACKING
(C51) 1
84 PISTON PIN 1
85 NEEDLE BEARING (A) 1
86 ENGINE CASE (A) 1
87 REAR DAMPER (C51) 1
88 BRAKE HANDLE 1
89 CAUTION LABEL 1
90 BRAKE LEVER SPRING (B) 1
91 CHOKE ROD RUBBER 1
92 CHOKE BUTTON 1
93 OPERATIONAL PANEL 1
94 STOP SWITCH 1
111 NAME PLATE 1
112 FLANGE NUT M8 3
113 SIDE CASE SUB 1
114 CHAIN PULLER 1
115 SAW CHAIN 1
116 GUIDE PLATE (B) 1
117 BAR 1
118 OIL GROMMET (A) 1
119 FUEL PIPE 1
120 BOLT WASHER D5 1
121 OIL FILTER 1
122 OIL FILTER BODY 1
123 GUIDE PLATE (A) 1
124 DAMPER (C51) 2
125 CHAIN CATCHER 1
126 BRAKE LINK 1
127 BRAKE SPRING 1
128 BRAKE BAND 1
129 NEEDLE ROLLER D3 1
ITEM
NO. PART NAME Q’TY
130 BRAKE LINK COVER 1
131 CLUTCH 1
132 CLUTCH WASHER (B) 1
133 CLUTCH HOUSING 1
134 NEEDLE BEARING 1
135 RIM SPROCKET 1
136 CLUTCH WASHER 1
137 OIL PUMP COVER (C51) 1
138 WORM 1
139 AIR VENT SPONGE 1
140 AIR VENT VALVE (B) 1
141 TAPPING SCREW
(W/FLANGE) D4
× 16 1
142 REAR HANDLE GRIP 1
143 THROTTLE LEVER
LOCKOUT 1
144 THROTTLE LEVER SPRING 1
145 NUMBER PLATE 1
146 REAR HANDLE 1
147 SPRING PIN 5
× 25 1
148 THROTTLE ROD 1
149 THROTTLE LEVER 1
150 AIR VALVE CAP 1
151 INNER CAP 1
152 GROMMET 1
153 PUMP FILTER BODY 1
154 FRONT DAMPER 1
155 SPRING HOLDER 2
156 FLANGED TAPPING SCREW
D6 2
157 ANTIVIBRATION SPRING 2
158 TANK MARK LABEL 1
159 TANK CAP PACKING 2
160 FUEL TANK CAP ASS'Y 2
161 BAND 1
162 PLUG CAP 1
163 CORD (A) 1
164 CORD (B) 1
165 METAL FITTING OF PLUG
CAP 1
166 IGNITION COIL 1
167 HEX. SOCKET HD. BOLT
(W/FLANGE) M4
× 18 2
168 MAGNETO ASS'Y 1
169 MAGNETO ROTOR 1
170 STARTER PAWL SPRING 2
171 WASHER 0.8 2
172 STARTER PAWL 2
173 SHIM 2
174 STEP BOLT 2
175 AIR DEFLECTOR 1
176 RECOIL STARTER 1
177 HITACHI LABEL 1
501 CHAIN COVER 1
502 COMBI BOX SPANNER 1
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Shinagawa Intercity Tower A, 15-1, Konan 2-chome,
Minato-ku, Tokyo, Japan
109
Code No. E99245511 G
Printed in China
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