Zenoah G2501 User manual

G2501
G2501 OPS
(One-Push-Start)
G
B
CHAIN SAWS
OWNER’S MANUAL
115860389 (1612)
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G2501 / G2501 OPS
GB-2
EXPLANATION OF SYMBOLS AND SAFETY WARNINGS
Read operator's instruction
book before operating this
machine.
Wear head, eye and ear
protection.
Use the chain saw
with two hands.
Warning! Danger of
kickback.
Read, understand and
follow all warnings.
This saw is for trained tree
service operators only.
Use appropriate protections
for foot-leg and hand-arm.
Contents
1. For Safe Operation.....................................................................3
2. Explanation of Symbols on the Machine....................................7
3. Installing Guide Bar and Saw Chain ..........................................8
4. Fuel and Chain Oil .....................................................................9
5. Operating the Engine...............................................................10
6. Sawing .....................................................................................12
7. Maintenance ............................................................................14
8. Maintenance of Saw Chain and Guide Bar..............................15
9. Troubleshooting Guide.............................................................16
10. Disposal ...................................................................................17
11. Specifications...........................................................................17
12. Limited Warranty ......................................................................18
Never touch hot surface.
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G2501 / G2501 OPS
GB-3
G
B
1. For safe operation
WARNING
This chainsaw has been especially designed for tree
maintenance and should therefore only be used by
trained operators when working on trees. National reg-
ulation can restrict the use. Long or continuous expo-
sure to high noise levels may cause permanent hearing
impairment. Always wear approved hearing protection.
1. Never operate a chain saw when you
are fatigued, ill, or upset, or under the
influence of medication that may
make you drowsy, or if you are under
the influence of alcohol or drugs.
2. Use the safety footwear shall have
slip-resistance protection, snug fit-
ting clothing and eye, hearing and
head protection devices.
Use the vibration-proof glove.
3. Keep the saw chain sharp and the
saw, including the AV system, well
maintained. A dull chain will increase
cutting time, and pressing a dull
chain through wood will increase the
vibrations transmitted to your hands.
A saw with loose components or with
damaged or worn AV buffers will also
tend to have higher vibration levels.
4. Always use caution when handling
fuel. Wipe up all spills and then move
the chain saw at least 3 m from the
fueling point before starting the en-
gine.
5. Eliminate all sources of sparks or
flame (i.e. smoking, open flames, or
work that can cause sparks) in the
areas where fuel is mixed, poured,
or stored.
6. Do not smoke while handling fuel or
while operating the chain saw.
7. Do not allow other persons to be near
the chain saw when starting or cut-
ting. Keep bystanders and animals
out of the work area. Children, pets
and bystanders should be a minimum
of 10 m away when you start or oper-
ate the chain saw.
8. Never start cutting until you have a
clear work area, secure footing,
and a planned retreat path from the
falling tree.
9. Always hold the chain saw firmly with
both hands when the engine is run-
ning. Use a firm grip with thumb and
fingers encircling the chain saw
handles.
10. Keep all parts of your body away from
the saw chain when the engine is run-
ning.
11. Before you start the engine, make
sure the saw chain is not contacting
anything.
12. Always carry the chain saw with the
engine stopped, the guide bar and
saw chain to the rear, and the muffler
away from your body.
13. Always inspect the chain saw before
each use for worn, Ioose, or dam-
aged parts. Never operate a chain
saw that is damaged, improperly
adjusted, or is not completely and
securely assembled. Be sure that the
saw chain stops moving when the
throttle control trigger is released.
14. All chain saw service, other than the
items listed in the Owner’s Manual,
should be performed by competent
chain saw service personnel. (E.g.,
if improper tools are used to remove
the flywheel, or if an improper tool is
used to hold the flywheel in order to
remove the clutch, structural damage
to the flywheel could occur which
could subsequently cause the fly-
wheel to disintegrate.)
15. Always shut off the engine before
setting it down.
16. Use extreme caution when cutting
small size brush and saplings be-
cause slender material may catch the
saw chain and be whipped toward
you or pull you off balance.
17. When cutting a limb that is under ten-
sion, be alert for spring- back so that
you will not be struck when the ten-
sion in the wood fibers is released.
18. Never cut in high wind, bad weather,
when visibility is poor or in very high
or low temperatures. Always check
the tree for dead branches which
could fall during the felling operation.
19. Keep the handles dry, clean and free
of oil or fuel mixture.
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G2501 / G2501 OPS
GB-4
20. Operate the chain saw only in well
ventilated areas. Never start or run
the engine inside a closed room or
building. Exhaust fumes contain dan-
gerous carbon monoxide. Warning
about the emission of lubrication oil
mist and saw dust.
21. Do not operate the chain saw in a tree
unless specially trained to do so.
22. Guard against kickback. Kickback is
the upward motion of the guide bar
which occurs when the saw chain at
the nose of the guide bar contacts
an object. Kickback can lead to dan-
gerous loss of control of the chain
saw.
23. When transporting your chain saw,
make sure the appropriate guide bar
scabbard is in place.
24. Never touch the muffer guard, guide
bar, saw chain or nut with bare hands
while the engine is in operation or im-
mediately after shutting down the
engine. Doing so could result in seri-
ous burns because of high tempera-
ture.
(1) muffler guard
(2) guide bar
(3) saw chain
element of surprise. Sudden surprise
contributes to accidents.
(2) Keep a good grip on the saw with
both hands, the right hand on the rear
handle, and the left hand on the front
handle, when the engine is running.
Use a firm grip with thumbs and fin-
gers encircling the chain saw
handles. A firm grip will help you re-
duce kickback and maintain control
of the saw.
(3) Make certain that the area in which
you are cutting is free from obstruc-
tions. Do not let the nose of the guide
bar contact a log, branch, or any
other obstruction which could be hit
while you are operating the saw.
(4) Cut at high engine speeds.
(5) Do not overreach or cut above shoul-
der height.
(6) Follow the manufacturer’s sharpening
and maintenance instructions for the
saw chain.
(7) Only use replacement bars and
chains specified by the manufacturer
or the equivalent.
KICKBACK SAFETY PRECAUTIONS
FOR CHAIN SAW USERS
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.
Tip contact in some cases may cause
a lightning fast reverse reaction,
kicking the guide bar up and back
towards the operator. Pinching the
saw chain along the top of the guide
bar may push the guide bar rapidly
back towards the operator. Either of
these reactions may cause you to
Iose control of the saw, which could
result in serious personal injury.
• Donotrelyexclusivelyonthesafety
devices built into your saw. As a chain
saw user you should take several
steps to keep cutting jobs free from
accident or injury.
(1) With a basic understanding of kick-
back you can reduce or eliminate the
WORSE EFFECTS OF VIBRATION
If you continue to use high-vibration tools these symp-
toms will probably get worse, for example:
• thenumbnessinyourhandscouldbecomeperma-
nent and you won’t be able to feel things at all;
• youwillhavedifcultypickingupsmallobjectssuch
as screws or nails;
• the vibration white nger could happen more fre-
quently and affect more of your fingers.
FOR PROTECTING YOUR BODY FROM VIBRATION
Please observe the following matter, in order to protect
the health of your body.
1. Always use the right tool for each job (to do the job
more quickly and expose you to less hand-arm vi-
bration).
2. Check tools before using them to make sure they
have been properly maintained and repaired to avoid
increased vibration caused by faults or general wear.
3. Make sure cutting tools are kept sharp so that they
remain efficient.
4. Reduce the amount of time you use a tool in one go,
by doing other jobs in between.
5. Avoid gripping or forcing a tool or workpiece more
than you have to.
6. Store tools so that they do not have very cold handles
when next used.
7. Encourage good blood circulation by:
• keeping warm anddry(whennecessary,wear
gloves, a hat, waterproofs and use heating pads if
available);
• giving uporcuttingdownonsmokingbecause
smoking reduces blood flow; and massaging and
exercising your fingers
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G2501 / G2501 OPS
GB-5
G
B
DISPOSAL
• When you dispose of the machine, do not disas-
semble the machine.
• Whenyoudisposeofthemachine,fuel,chainoil,
be sure to follow your local regulations.
WORKING WITH TREE SERVICE CHAIN-SAWS
FROM A ROPE AND HARNESS
This chapter sets out working practices to reduce the
risk of injury from tree service chainsaws when working
at height from a rope and harness. While it may form
the basis of guidance and training literature, it should
not be regarded as a substitute for formal training.
General requirements working at height
Operators of tree service chainsaws working at height
from a rope and harness should never work alone. A
competent ground worker trained in appropriate emer-
gency procedures should assist them.
Operators of tree service chainsaws for this work should
be trained in general safe climbing and work position-
ing techniques and shall properly equipped with har-
nesses, ropes, strops, karabiners and other equipment
for maintaining secure and safe working positions for
both themselves and the saw.
Preparing to use the saw in the tree
The chainsaw should checked, fuelled, started and
warmed up by the ground worker before it is sent up to
the operator in the tree. The chainsaw should be fitted
with a suitable strop for attaching to the operator’s har-
ness:
a) choke the strop around the attachment point on the
rear of the saw (A);
b) provide suitable karabiners to allow indirect (i.e. via
the strop) and direct attachment (i.e. at the attach-
ment point on the saw) of saw to the operators har-
ness;
c) ensure the saw is securely attached when it is being
sent up to the operator;
d) ensure the saw it secured to the harness before it is
disconnected from the means of ascent.
The saw should only be attached to the recommended
attachment points on the harness. These may be at
mid-point (front or rear) or at the sides. Where possible
attaching the saw to centre rear mid-point will keep it
clear of climbing lines and support its weight centrally
down the operator’s spine.
When moving the saw from any attachment point to an-
other, operators should ensure it is secured in the new
position before releasing it from the previous attachment
point.
Using the chainsaw in the tree
An analysis of accidents with these saws during tree
service operations shows the primary cause as being
inappropriate one-handed use of the saw. In the vast
majority of accidents, operators fail to adopt a secure
work position witch allows them to hold both handles of
the saw. This results in an increased risk of injury due
to:
•nothavingarmgriponthesawifitkicksback;
• alackofcontrolofthesawsuchthatitismoreliable
to contact climbing lines and operators body (par-
ticularly the left hand and arm)
• losingcontrolfrominsecureworkpositionresultingin
contact with the saw (unexpected movement during
operation of the saw)
Securing the work position for two-handed use
To allow the operator to hold the saw with both hands,
they should as general rule, aim for secure work posi-
tion where they are operating the saw at:
• hiplevelwhencuttinghorizontalsections;
• solarplexuslevelwhencuttingverticalsections.
Where the operator is working close into vertical stems
with a low lateral forces on their work position, then a
good footing may be all that is needed to maintain a
secure work position. However as operators move away
from the stem, they will need to take steps to remove or
counteract the increasing lateral forces by, for example,
a re-direct of the main line via a supplementary anchor
point or using an adjustable strop direct from the har-
ness to a supplementary anchor point.
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G2501 / G2501 OPS
GB-6
Gaining a good footing at the working position can be
assisted by use of a temporary foot stirrup created from
an endless sling.
Starting the saw in the tree
When starting the saw in the tree, the operator should:
a) apply the chain brake before starting;
b) hold saw on either the left or right of the body when
starting:
1) on the left side hold the saw with either the left hand
on the front handle or the right hand on the rear
handle and thrust the saw away from the body while
holding the pull starter cord in the other hand;
2) on the right side, hold the saw with the right hand on
either handle and thrust the saw away from the body
while holding the pull starter cord in the left hand.
The chain brake should always be engaged before low-
ering a running saw onto its strop.
Operators should always check the saw has sufficient
fuel before undertaking critical cuts.
One-hand use of the chainsaw
Operators should not use tree service chainsaws one-
handed in place of unstable work positioning or in pref-
erence to a handsaw when cutting small diameter wood
at the branch tips.
Tree service chainsaws should only be used one-handed
where:
• theoperatorcannotgainaworkpositionenablingtwo-
handed use; and
• theyneedtosupporttheirworkingpositionwithone
hand; and
• thesawisbeingusedatfullstretch,atrightanglesto
and out of line with the operator’s body.
Operators should never:
• cutwiththekickbackzoneatthetipofthechainsaw
guide bar
• ‘holdandcut’sections
• attempttocatchfallingsections.
Freeing a trapped saw
If the saw should become trapped during cutting, op-
erators should:
• switchoffthesawandattachitsecurelytothetree
inboard (i.e. towards the truck side) of the cut or to a
separate tool line;
• pullthesawfromthekerfwhilstliftingthebranchas
necessary;
• ifnecessary,useahandsaworsecondchainsawto
release the trapped saw by cutting a minimum of 30
cm away from the trapped saw.
Whether a handsaw or a chainsaw is used to free a stuck
saw, the release cuts should always be outboard (to-
ward the tips of the branch), in order to prevent the saw
being taken with the section and further complicating
the situation.
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G2501 / G2501 OPS
GB-7
G
B
The port to refuel “MIX GASOLINE”
Position: Fuel cap
The port to top up chain oil
Position: Oil cap
Setting the switch to the “O” position, the engine stops immediately.
Position: Front at the top of the rear handle
Starting the engine. If you pull out the choke knob (at the back-right of
the rear handle) to the point of the arrow, you can set the starting mode
as follows:
•First-stage position – starting mode when the engine is warm.
•Second-stage position – starting mode when the engine is cold.
Position: Upper-right of the aircleaner cover
The screw under the “H” stamp is The High-speed adjustment screw.
The screw under the “L” stamp is The Slow-speed adjustment screw.
The screw at the left of the “T” stamp is the Idle adjustment screw.
Position: Left side of the rear handle
If you turn the rod by screwdriver follow the arrow to the "MAX" position,
the chain oil flow more, and if you turn to the "MIN" position, less.
Position: Bottom of the power unit
<G2501 One-push-start only>
A : Indicates the operation selecting position of the select lever for the
One-push-start and Super e-START at a start of the recoil.
B : Indicates the operating direction of the select lever at a start of the
engine by One-push-start.
Position: Upper side portion of the recoil starter
2. Explanation of Symbols on the Machine
For safe operation and maintenance, symbols are carved in relief on the machine.
According to these indications, please be careful not to make any mistake.
B
A
WARNING
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G2501 / G2501 OPS
GB-8
Open the box and install the guide bar and the saw
chain on the power unit as follows:
WARNING
The saw chain has very sharp edges. Use thick pro-
tective gloves for safety.
1. Pull the guard towards the front handle to check that
the chain brake is not engaged.
2. Loosen the nuts and remove the chain cover.
3. Fix the hanger on the rear of power unit by screw.
Hanger
4. Mount the guide bar then fit the saw chain around
the bar and sprocket.
Chain tensioner nut
Hole
Chain cover
NOTE
Pay attention to the correct direction of the saw chain.
Moving direction
5. Fit the chain tensioner nut into the lower hole of the
guide bar, then install the chain cover, and fasten
the mounting nut to finger tightness.
WARNING
When installing the chain cover, be sure to fit the hook
completely at the rear end of the cover.
6. While holding up the tip of the bar, adjust the chain
tension by turning the tensioner screw until the tie
straps just touch the bottom side of the bar rail.
Tensioner screw
Loosen
Tighten
7. Tighten the nuts securely with the bar tip held up
(11.8-14.7 N.m./120-150 kg-cm). Then check the
chain for smooth rotation and proper tension while
moving it by hand. If necessary, readjust with the
chain cover loose.
Tighten
8. Tighten the tensioner screw.
WARNING
A new chain will expand its length in the beginning of
use. Check and readjust the tension frequently as a loose
chain can easily derail or cause rapid wear of itseif and
the guide bar.
3. Installing Guide Bar and Saw Chain
Plug wrench
File
Grip
Choke knob
Throttle lever
Engine switch Saw chain
Bag
Guide bar
Muffler
Air cleaner cover Chain catcher
Chain cover
A standard saw unit package contains the items as illustrated.
Screwdriver for
carburetor adjustment
Bar protector
Guide bar
Saw chain
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G2501 / G2501 OPS
GB-9
G
B
■ FUEL
WARNING
• Gasoline is very flammable. Avoid smoking or bringing
any flame or sparks near fuel. Make sure to stop the en-
gine and allow it cool before refueling the unit. Select
outdoor bare ground for fueling and move at least 3 m
(10 ft) away from the fueling point before starting the
engine.
• TheZenoahenginesarelubricatedbyoilspeciallyformu-
latedforair-cooled2-strokegasolineengineuse.IfZenoah
oil is not available, use an anti-oxidant added quality oil ex-
pressly labeled for air-cooled 2-stroke engine use (JASO FD
GRADE OIL or ISO-L-EGD GRADE).
• DonotuseBIAorTCW(2-strokewater-coolingtype)mixed
oil.
■ RECOMMENDED MIXING RATIO
GASOLINE 50 : OIL 1
<when using ZENOAH genuine oil>
(JASO FD GRADE OIL or ISO-L-EGD GRADE)
• Exhaust emission are controlled by the fundamental
engine parameters and components (eq., carburation,
ignition timing and port timing) without addition of any
major hardware or the introduction of an inert material
during combustion.
• Theseenginesarecertiedtooperateonunleadedgaso-
line.
• Makesuretousegasolinewithaminimumoctanenumber
of 89RON (USA/Canada: 87AL).
• Ifyouuseagasolineofaloweroctanevaluethanprescribed,
there is a danger that the engine temperature may rise and
an engine problem such as piston seizing may consequently
occur.
• Unleadedgasolineisrecommendedtoreducethecontami-
nation of the air for the sake of your health and the environ-
ment.
• Poor quality gasolines or oils may damage sealing rings,
fuel lines or fuel tank of the engine.
■ HOW TO MIX FUEL
WARNING
•Payattentiontoagitation.
1. Measure out the quantities of gasoline and oil to be mixed.
2. Put some of the gasoline into a clean, approved fuel con-
tainer.
3. Pour in all of the oil and agitate well.
4. Pour in the rest of gasoline and agitate again for at least
one minute. As some oils may be difficult to agitate de-
pending on oil ingredients, sufficient agitation is neces-
sary for the engine to last long. Be careful that, if the agita-
tion is insufficient, there is an increased danger of early
piston seizing due to abnormally lean mixture.
5. Put a clear indication on the outside of the container to
avoid mixing up with gasoline or other containers.
6. Indicate the contents on outside of container for easy iden-
tification.
■ FUELING THE UNIT
1. Untwist and remove the fuel cap. Rest the cap on a dust-
less place.
2. Put fuel into the fuel tank to 80% of the full capacity.
3. Fasten the fuel cap securely and wipe up any fuel spillage
around the unit.
WARNING
1. Select bare ground for fueling.
2. Move at least 10 feet (3 meters) away from the fueling point
before starting the engine.
3. Stop the engine before refueling the unit. At that time, be
sure to sufficiently agitate the mixed gasoline in the con-
tainer.
■ FOR YOUR ENGINE LIFE, AVOID:
1. FUEL WITH NO OIL (RAW GASOLINE) – It will cause se-
vere damage to the internal engine parts very quickly.
2. GASOHOL – It can cause deterioration of rubber and/or
plastic parts and disruption of engine lubrication.
3. OIL FOR 4-STROKE ENGINE USE – It can cause spark
plug fouling, exhaust port blocking, or piston ring sticking.
4. Mixed fuels which have been left unused for a period
of one month or more may clog the carburetor and result
in the engine failing to operate properly.
5. In the case of storing the product for a long period of time,
clean the fuel tank after rendering it empty. Next, activate
the engine and empty the carburetor of the composite fuel.
6. In the case of scrapping the used mixed oil container, scrap
it only at an authorized repository site.
NOTE
As for details of quality assurance, read the description in the
section Limited Warranty carefully. Moreover, normal wear and
change in product with no functional influence are not covered
by the warranty. Also, be careful that, if the usage in the in-
struction manual is not observed as to the mixed gasoline, etc.
described therein, it may not be covered by the warranty.
■ SUPPLYING CHAIN OIL
WARNING
Running the equipment for long hours with its chain oil run out
will accelerate the wear and tear of the chain and guide bar,
possibly resulting further in a chain cut and even in a fatal
accident leading to death.
1. For chain oil, use a type that is sufficiently viscous and
adequately lubricating under the summer-use conditions
and another type that shows similar performance under
the winter-use conditions.
2. TheuseofZonoahgenuinechainoilisrecommendedto
make your chain saws last as long as possible. If no genu-
ine chain oil is available, please use commercially avail-
able chain oil, which is commonly used.
CAUTION
Using waste oil, recycled oil, or anything similar causes a break-
down and also proves harmful to the human body and envi-
ronment. Please do not under any circumstances use any such
material.
IMPORTANT
Use chain oil of vegetable origin. Before storing it for a long
period, remove the chain oil from the blade and chain groove
and clean them. If not, the chain may become rusted. Chain
rust will cause the chain to become rigid or to become viscous
at the tip.
4. Fuel and Chain Oil
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G2501 / G2501 OPS
GB-10
WARNING
It is very dangerous to run a chainsaw that mounts broken
parts or lacks any parts.
Before starting engine, make sure that all the parts includ-
ing bar and chain are installed properly.
■ STARTING THE ENGINE
Normal start
1. Fill fuel and chain oil tanks respectively, and tighten
the caps securely.
Chain oil
Fuel
2. Continuously push the priming bulb until fuel comes
in the bulb.
3. Set the switch to “I” position.
Switch
Throttle
interlock
Throttle
lever
(G2501 OPS)
• Move the select lever to the machine back side
indicated by label until it is stopped, and then set
this lever to the recoil start mode.
Select lever Select lever
operating direction
Label
4. Pull out the choke knob to the second-stage position.
The choke will close and the throttle lever will then
be set in the starting position.
Choke
knob
When the engine is cool
When the engine is warm up
After the engine starts
NOTE
When restarting immediately after stopping the en-
gine, set the Choke knob in the first-stage position
(choke open and throttle lever in the starting posi-
tion).
Once the choke knob has been pulled out, it will not
return to the operating position even if you press
down on it with your finger. When you wish to return
the choke knob to the operating position, pull out
the throttle lever instead.
5. While holding the saw unit securely on the ground,
pull the starter rope vigorously.
WARNING
Do not start the engine while the chain saw hangs in
one hand. The saw chain may touch your body. This
in very dangerous.
6. When engine has ignited, first push in the choke knob
to the first-stage position and then pull the starter
again to start the engine.
7. Allow the engine to warm up with the throttle lever
pulled slightly.
One-push-start
(G2501 OPS only)
WARNING
• UseOne-push-startafterperformingwarming-up by
Recoil Start in the status where the machine body is
securely fixed. You can not use OPS when the engine
is cold.
• Thestartingperformanceoftheenginedependson
the adjustment of the engine. Ask the distributor to
adjust the engine if possible.
• Be careful not to set OPS in motion except when
starting the engine. If so, it may lead to serious injury.
1. Move the select lever to the front side of the machine
body indicated by label until it is stopped, and set
this lever to the One-push-start mode.
5. Operating the Engine
*01_G2501 G2501ops_GB_CS5_六.indd 10 16/09/21 16:49

G2501 / G2501 OPS
GB-11
G
B
2. Put the machine body on the stable ground and make
sure that there is no obstacle around the saw-crossing
portion. Then, while holding the front handle with the
left hand and putting the right foot on the frame portion,
pull out the starter rope slowly.
NOTE
The rope may be pulled out little by little several times.
WARNING
• Whenpullingouttherope,largeclangingisproduced.
With this clanging, stop pulling out the rope at once.
This sound notifies that One-push-start has been set.
• Don’tpullouttheropeexcessivelyordon’tpullitout
without load by the starter only, otherwise a starter
failure will occur.
3. Before starting the engine, fix the engine securely
and make sure that there is no obstacle around the
saw chain. Then, push the top of the engine stop
switch on the right side of the rear handle and set it
to the “Run” position. After that, move the select le-
ver to the rear side of the machine body indicated
by label. The starter is started to start the engine.
I (Run) O (Stop) Engine stop switch
Select lever
Label
NOTE
If the engine cannot be started by the above proce-
dure, repeat the above operations again. If the engine
cannot be started smoothly, it may be necessary to
add warming-up or readjust the engine. Perform
warming-up enough and ask the distributor to readjust
the engine.
■ FOR SMOOTHER USE OF ONE-PUSH-START
To use One-push-start more smoothly, it is important to
perform warming-up longer than ever.
1. When the outside temperature is 0° or more, perform
warming-up for about 5 seconds with the throttle fully
opened. And leave the product for 5 minutes or less
after the engine stops. Then, use the product. With
this, the engine can be started more securely.
2. When the outside temperature is below 0°C, repeat
the above warming-up operation twice or more. After
the engine stops, use the product in a shorter leaving
time.
WARNING
• Besuretoperformwarming-upwiththeguidebar
and the saw chain mounted.
• KeepclearofthesawchainasitwillstartrotatIng
upon starting of engine.
• Beforeyoustarttheengine,makesurethesawchain
is not contacting anything.
■ CHECKING THE OIL SUPPLY
WARNING
Make sure to set up the bar and the chain when
checking the oil supply.
If not, the rotating parts may be exposed. It is very
dangerous.
After starting the engine, run the chain at medium speed
and see if chain oil is scattered off as shown in the fig-
ure.
Chain oil
The chain oil flow can be changed by inserting a
screwdriver in the hole on bottom of the clutch side.
Adjust according to your work conditions.
Rich Chain oil flow
adjusting shaft
Lean
The oil tank should become nearly empty by the time
fuel is used up. Be sure to refill the oil tank every time
when refueling the saw.
■ ADJUSTING THE CARBURETOR
L needle
H needle
Idle adjusting
screw
The carburetor on your unit has been factory adjusted,
but may require fine tuning due to a change in operat-
ing conditions.
Before adjusting the carburetor, make sure that the pro-
vided air/fuel filters are clean and fresh and the fuel prop-
erly mixed.
When adjusting, take the following steps:
NOTE
Be sure to adjust the carburetor with the bar chain at-
tached.
*01_G2501 G2501ops_GB_CS5_六.indd 11 16/09/21 16:49

G2501 / G2501 OPS
GB-12
■ STOPPING THE ENGINE
1. Release the throttle lever to allow the engine to idle
for a few minutes.
2. Set the switch to the “O” (STOP) position.
Switch
6. Sawing
1. H and L needles are restricted within the number of
turn as shown below.
H needle : 1 1/2 ± 1/4
L needle
: 2 ± 1/4
2. Start the engine and allow it to warm up in low speed
for a few minutes.
3. Turn the idle adjusting screw (T) counterclockwise
so that the saw chain does not turn. If the idling
speed is too slow, turn the screw clockwise.
4. Make a test cut and adjust the H needle for best
cutting power, not for maximum speed.
• Before proceeding to your job,
read the section “For Safe
Operation”. It is recommended
to first practice sawing easy
logs. This also helps you get
accustomed to your unit.
• Always follow the safety regu-
lations. The chain saw must
only be used for cutting wood.
It is forbidden to cut other
types of material. Vibrations
and kickback vary with differ-
ent materials and the require-
ments of the safety regulations
would not be respected. Do
not use the chain saw as a le-
ver for lifting, moving or split-
ting objects. Do not lock it over
fixed stands. It is forbidden to
hitch tools or applications to
the PTO other than those
specified by the manufacturer.
• It is not necessary to force the
saw into the cut. Apply only
light pressure while running the
engine at full throttle.
• When the saw chain is caught
in the cut, do not attempt to pull
it out by force, but use a wedge
or a lever to open the way.
• Iftheguidebarandsawchain
becomes caught in wood while
operating it, stop the engine.
Do not pry the handle with ex-
cessive force. Use a wedge to
remove the chain instead.
■ GUARD AGAINST KICKBACK
To prevent kickback, do not use the tip of the guide
bar for cutting.
■ FELLING A TREE
Notch cut Felling cut
Felling direction
1. Decide the felling direction considering the wind,
lean of the tree, location of heavy branches, ease of
completing the task after felling and other factors.
2. While clearing the area around the tree, arrange a
good foothold and retreat path.
3. Make a notch cut one-third of the way into the tree
on the felling side.
4. Make a felling cut from the opposite side of the notch
and at a level slightly higher than the bottom of the
notch.
WARNING
When you fell a tree, be sure to warn neighboring work-
ers of the danger.
WARNING
*01_G2501 G2501ops_GB_CS5_六.indd 12 16/09/21 16:49

G2501 / G2501 OPS
GB-13
G
B
Cutting the limbs of Fallen Tree
First check to which side the limb is bent. Then make
the initial cut from the bent side and finish by sawing
from the opposite side.
WARNING
Be alert to the springing back of a cut limb.
Pruning of Standing Tree
Cut up from the bottom, finish down from the top.
WARNING
• Donotuseanunstablefootholdorladder.
• Donotoverreach.
• Donotcutaboveshoulderheight.
• Alwaysusebothyourhandstoholdthesaw.
Bucking and Limbing
WARNING
• Alwaysensureyourfoothold.Donotstandonthelog.
• Bealerttotherollingoverofacutlog.Especiallywhen
working on a slope, stand on the uphill side of the
log.
• Followtheinstructionsin“ForSafeOperation”toavoid
kickback of the saw.
Before starting work, check the direction of bending
force inside the log to be cut. Always finish cutting from
the opposite side of the bending direction to prevent
the guide bar from being caught in the cut.
A log lying on the ground
Saw down halfway, then roll the log over and cut from
the opposite side.
A log hanging off the ground
In area A, saw up from the bottom one-third and finish
by sawing down from the top. In area B, saw down from
the top one-third and finish by sawing up from the bot-
tom.
*01_G2501 G2501ops_GB_CS5_六.indd 13 16/09/21 16:49

G2501 / G2501 OPS
GB-14
WARNING
When returning the filter, use a pinch not to be folded the suc-
tion pipe.
3. Oil filter
1. With a wire hook, take out the oil filter from the feeding
port.
Oil filter
2. Wash the filter with gasoline.
WARNING
When returning the filter, use a pinch not to be folded the suc-
tion pipe.
4. Spark plug
Champion
RCJ-7Y
Clean the electrodes with a wire brush and reset the gap to
0.6 mm as necessary.
5. Sprocket
Check for cracks and for excessive wear interfering with the
chain drive. If the wear is considerable, replace it with new
one. Never fit a new chain on a worn sprocket, or a worn chain
on a new sprocket.
6. Way of the cooling air
WARNING
• Theenginemetalpartscanburnyourskin.Nevertouchthe
cylinder, muffler or ignition plug etc. during operation or right
after stopping the engine.
• Before starting the engine, check around the mufer and
take off sawdust. If you do not, it will cause the overheating
and a fire. For preventing the trouble, please keep clean
around the muffler.
This engine is air-cooled. Dust clogging between the inlet port
of the cooling air and cylinder fins will cause overheating of
the engine. Periodically check and clean the cylinder fins after
removing the air cleaner and the cylinder cover.
inlet port of the cooling air
IMPORTANT
When installing the cylinder cover, make sure that switch wires
and grommets are positioned correctly in place.
WARNING
Before cleaning, the inspecting or repairing the unit, make sure
that engine has stopped and is cool. Disconnect the spark
plug to prevent accidental starting.
■ MAINTENANCE AFTER EACH USE
1. Air filter
Loosen the knob and remove the air cleaner cover. Take off the
filter elements and tap off attached sawdust. When they are
extremely dirty, shakewash with gasoline. Dry them completely
before reinstalling.
2. Oiling port
Dismount the guide bar and check the oiling port for clogging.
Oiling port
3. Guide bar
When the guide bar is dismounted, remove sawdust in the bar
groove and the oiling port.
<Type : sprocket nose>
Grease the nose sprocket from the feeding port on the tip of
the bar.
Oiling port
Grease port
Sprocket
4. Others
Check for fuel leakage and loose fastenings and damage to
major parts, especially handle joints and guide bar mounting.
If any defects are found, make sure to have them repaired
before operating the saw again.
■ PERIODICAL SERVICE POINTS
1. Cylinder fins
1. Remove the starter case.
2. Remove sawdust between the cylinder
fins.
3. Clean the valute area.
2. Fuel filter
(a) Using a wire hook, take out the filter from the filler port.
Fuel filter
(b) Wash the filter with gasoline.
Replace with new one if clogged with dirt completely.
7. Maintenance
*01_G2501 G2501ops_GB_CS5_六.indd 14 16/09/21 16:49

G2501 / G2501 OPS
GB-15
G
B
8. Recoil Starter
• Forrecoilmaintenance,whenattachingordetachingthe
starter of One-push-start model, the select lever should
be in the position of the rear side (G2501 One-push-start
only).
• Don'tpullthestarterwhendetachingitfromtheunit.Itwill
cause machine defect or serious injury by touching rotat-
ing parts on your body part carelessly.
Set direction
Select lever
WARNING
Don'tpullthestarterwhendetachingitfromtheunit.
7. Muffler
WARNING
If you do not attach the muffler correctly, after engine starts,
the muffler will be loosen and the hightemperature exhaust
gas spout. After cleaning the muffler, pay attention to fit up
the muffler according to the explanation as follows.
1. Muffler body, muffler cover and baffle will be combined
correctly.
2. Be sure the gasket is not broken. If it is broken, change to
the new one.
3. Before tightening the screw, rub the gross on it.
4. After making a test run, re-tighten the screw (TORQUE:
6.9-7.8 N.m./70-80 kg-cm)
WARNING
Right after stopping the engine, do not touch the muffler with
one'sbarehands.Itwillcausetoburnyourhands.
If carbon clogs between the muffler, it will cause the poor-out-
put and the trouble in starting. After each 100 hours, check
and clean inside the muffler.
■ Saw Chain
WARNING
It is very important for smooth and safe operation to
always keep the cutters sharp.
The cutters need to be sharpened when:
• Sawdustbecomespowder-like.
• Youneedextraforcetosawin.
• Thecutpathdoesnotgostraight.
• Vibrationincreases.
• Fuelconsumptionincreases.
Cutter setting standards:
WARNING
Be sure to wear safety gloves.
Before filing:
• Makesurethesawchainisheldsecurely.
• Makesuretheengineisstopped.
• Usearoundleofpropersizeforthechain.
Chain type: 25AP
File size: 5/32 in (4.0 mm)
Place the file on the cutter and push straight forward.
Keep the file position as illustrated.
After each cutter has been filed, check the depth gauge
and file it to the proper level as illustrated.
Appropriate gauge checker
Make the shoulder round
Depth gauge standard
.025ʺ(0.64 mm)
8. Maintenance of Saw Chain and Guide Bar
*01_G2501 G2501ops_GB_CS5_六.indd 15 16/09/21 16:49

G2501 / G2501 OPS
GB-16
of the bar rail. Apply a ruler to the bar and the out
side of a cutter. If a gap is observed between them,
the rail is normal. Otherwise, the bar rail is worn.
Such a bar needs to be corrected or replaced.
Ruler
Gap
No gap
Chain tilts
WARNING:
This saw is equipped with one of the following low
kickback bar/chain combinations:
ZenoahPartNumber
Bar Size Guide Bar Saw Chain Drum
10 2982-52111 3622-52210 T2041-51110
Case 1. Starting failure
WARNING
Make sure the icing prevention system is not work-
ing.
WARNING
Be sure to round off the front edge to reduce the
chance of kickback or tie-strap breakage.
Make sure every cutter has the same length and edge
angles as illustrated.
Cutter length
Filing angle
Side plate angle
Top plate cutting angle
■ Guide Bar
• Reversethebaroccasionallytopreventpartialwear.
• Thebarrailshouldalwaysbesquare.Checkforwear
9. Troubleshooting Guide
Check fuel for water
or substandard mix-
ture.
Replace with proper
fuel.
Check for engine
flooding.
Check spark ignition.
Remove and dry the
spark plug.
Then pull the starter
again with no choke.
Replace with a new
plug.
Case 2. Lack of power/Poor acceleration/
Rough idling
Case 3. Oil does not come out
Check fuel for water
or substandard mix-
ture.
Check air filter and
fuel filter for clog-
ging.
Check carburetor
for inadequate ad-
justment.
If the unit seems to need further service, please consult
with an authorized service shop in your area.
Replace with proper
fuel.
Clean.
Readjust speed
needles.
Check oil for sub-
standard quality.
Check oil passage
and ports for clog-
ging.
Replace.
Clean.
a
d
d
a
a
d
d
a
a
a
d
a
a
*01_G2501 G2501ops_GB_CS5_六.indd 16 16/09/21 16:49

G2501 / G2501 OPS
GB-17
G
B
• When you dispose of the machine, do not disas-
semble the machine.
• Whenyoudisposeofthemachine,fuel,chainoil,
be sure to follow your local regulations.
11. Specifications
G2501 OPS (One-push-start)
Dimensions (L x W x H) (mm):............. 260 x 220 x 210
Dry weight
Power unit only (kg):.................................................2.8
Power:.......................................... 0.88/9,000 (kw/min-1)
Cutting head:
<Sprocket bar>
Sprocket: ...................................................................8T
Chain speed at max. power ..........................15.2 (m/s)
Guide bar
Type:..................................................Sprocket nose
Size (in. (cm)): .............................................. 10 (25)
Saw chain
Type:................................................... Oregon 25AP
Pitch (in. (mm)): ........................................ 1/4 (6.35)
Gauge (in. (mm)): ................................... 0.05 (1.27)
Power unit:
G2501 / G2501 OPS
Displacement (cm3):...............................................25.4
Fuel:..................Mixture (Gasoline 50 : Two-cycle oil 1)
(whenusingZENOAHgenuineoil)
Fuel tank capacity (cm3):.........................................230
Chain oil:...................................Motor oil SAE# 10W-30
Oil tank capacity (cm3): ...........................................160
Carburetor: ..........................................Diaphragm type
lgnition system::............................................Solid State
Spark plug:...................................... Champion RCJ-7Y
Oil feeding system:...........................Mechanical pump
Max. speed..............................................12,500 (min-1)
Idle speed .................................................2,900 (min-1)
G2501
Dimensions (L x W x H) (mm):............. 260 x 220 x 210
Dry weight
Power unit only (kg):.................................................2.6
Power:.......................................... 0.88/9,000 (kw/min-1)
10. Disposal
*01_G2501 G2501ops_GB_CS5_六.indd 17 16/09/21 16:49

G2501 / G2501 OPS
GB-18
12. Limited warranty
Should any failure occur on the product under normal
operating conditions within the applicable warranty peri-
od, the failed part will be replaced or repaired free of
chargebyaZENOAHauthorizeddealer.
WARRANTY PERIOD: Six (6) months after purchased
by end-user subject to 12 months from produced month.
(30 days if used for rental purpose)
THE PURCHASER SHALL BEAR COSTS OF TRANS-
PORTINGTHEUNITTO ANDFROMTHE ZENOAH
DEALER.
THE PURCHASER SHALL NOT BE CHARGED FOR DI-
AGNOSTIC LABOR WHICH LEADS TO THE DETERMI-
NATION THAT A WARRANTED PART IS DEFECTIVE, IF
THE DIAGNOSTIC WORK IS PERFORMED AT THE
ZENOAHDEALER.
THE PURCHASER OR OWNER IS RESPONSIBLE FOR
THE PERFORMANCE OF THE REQUIRED MAINTE-
NANCE AS DEFINED BY THE MANUFACTURER IN THE
OWNER/OPERATOR MANUAL.
ANY WARRANTED PART WHICH IS NOT SCHEDULED
FOR REPLACEMENT AS REQUIRED MAINTENANCE,
OR WHICH IS SCHEDULED ONLY FOR REGULAR IN-
SPECTION TO THE EFFECT OF REPAIR OR “REPLACE
AS NECESSARY” SHALL BE WARRANTED FOR THE
WARRANTY PERIOD. ANY WARRANTED PART WHICH
IS SCHEDULED FOR REPLACEMENT AS REQUIRED
MAINTENANCE SHALL BE WARRANTED FOR THE
PERIOD OF TIME UP TO THE FIRST SCHEDULED RE-
PLACEMENT POINT FOR THE PART.
ANY REPLACEMENT PART THAT IS EQUIVALENT IN
PERFORMANCE AND DULABILITY MAY BE USED IN
NON-WARRANTY MAINTENANCE OR REPAIRS, AND
SHALL NOT REDUCE THE WARRANTY OBLIGATION
OF THE COMPANY.
THE COMPANY IS LIABLE FOR DAMAGES TO OTHER
ENGINE COMPONENTS CAUSED BY THE FAILURE OF
A WARRANTED PART STILL UNDER WARRANTY.
THE WARRANTY DOES NOT APPLY TO THOSE
UNITS WHICH HAVE BEEN DAMAGED BY NEGLI-
GENCE OF INSTRUCTION LISTED IN THE OWNER/
OPERATOR MANUAL FOR PROPER USE AND MAIN-
TENANCE OF THE UNITS ACCIDENT MISHANDLING,
ALTERATION, ABUSE, IMPROPER LUBRICATION, USE
OF ANY PARTS OR ACCESSORIES OTHER THAN
THOSE SPECIFIED BY THE COMPANY, OR OTHER
CAUSESBEYONDTHECOMPANY'SCONTROL.
THIS WARRANTY DOES NOT COVER THOSE PARTS
REPLACED BY NORMAL WEAR OR HARMLESS
CHANGES IN THEIR APPEARANCE.
THERE ARE NO OTHER EXPRESS WARRANTIES.
ANY IMPLIED WARRANTY is limited to the duration of the
limited warranty. Otherwise, this limited warranty is in lieu of
all other expressed or implied warranties, including any
warranty of FITNESS FOR A PARTICULAR PURPOSE
OR USE and any implied warranty MERCHANTABILITY
otherwise applicable to this product.
LIABILITIES FOR INCIDENTAL OR CONSEQUENTIAL
DAMAGE UNDER ANY AND ALL WARRANTIES ARE
EXCLUDED.
IF YOU NEED TO OBTAIN MORE INFORMATION,
PLEASE CALL YOUR NEAREST SERVICE CENTER, OR
CHECKPLEASEZENOAHWEBSITEhttp://
www.zenoah.net
*01_G2501 G2501ops_GB_CS5_六.indd 18 16/09/21 16:49