Harbor Freight Tools 66908 Installation manual
16” 37CC GAS CHAIN SAW
66908
18” 45CC GAS CHAIN SAW
66909
SET UP AND OPERATING INSTRUCTIONS
Using an engine indoors CAN KILL YOU IN
MINUTES.
Engine exhaust contains carbon monoxide.
This is a poison you cannot see or smell.
NEVER use inside
a home or garage,
EVEN IF doors and
windows are open.
Only use OUTSIDE
and far away from
windows, doors, and
vents.
Visit our website at: http://www.harborfreight.com
Read this material before using this product.
Failure to do so can result in serious injury.
SAVE THIS MANUAL.
Copyright©2009 by Harbor Freight Tools®. All rights reserved. No portion of this manual or any artwork
contained herein may be reproduced in any shape or form without the express written consent of
Harbor Freight Tools. Diagrams within this manual may not be drawn proportionally. Due to continuing
improvements, actual product may differ slightly from the product described herein. Tools required for
assembly and service may not be included.
For technical questions or replacement parts, please call 1-800-444-3353.
Manual Revised 09j
Page 2 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
CONTENTS
IMPORTANT SAFETY
INFORMATION ............................ 3
GENERAL POWER TOOL
SAFETY WARNINGS.......................3
VIBRATION SAFETY .........................7
SPECIFICATIONS.......................... 8
SKU 66908 16” 37CC ........................8
SKU 66909 18” 45CC ........................8
UNPACKING .................................. 8
CHAIN SAW COMPONENTS ...... 10
MAIN CONTROLS ............ 11
OPERATING INSTRUCTIONS .... 11
TOOL SET UP .................................. 11
GENERAL OPERATING
INSTRUCTIONS ............................13
BASIC FELLING, LIMBING, AND
BUCKING CUT TECHNIQUES......14
MAINTENANCE AND
SERVICING ............................... 17
CLEANING, MAINTENANCE, AND
LUBRICATION ...............................17
CLEANING, MAINTENANCE, AND
LUBRICATION SCHEDULE ..........21
STORAGE ........................................22
TROUBLESHOOTING......................22
PARTS LIST FOR SKU 66908
16” 37CC GAS CHAIN SAW..... 24
PARTS LIST FOR SKU 66908
16” 37CC GAS CHAIN SAW
(cont.)..................................................25
ASSEMBLY DIAGRAM - SKU
66908 16” 37CC CHAIN SAW... 26
PARTS LIST FOR SKU 66909
18” 45CC GAS CHAIN SAW..... 28
PARTS LIST FOR SKU 66909
18” 45CC GAS CHAIN SAW..... 29
ASSEMBLY DIAGRAM - SKU
66909 18” 45CC CHAIN SAW... 30
ASSEMBLY DIAGRAM - SKU
66909 18” 45CC CHAIN SAW... 31
ASSEMBLY DIAGRAM - SKU
66909 18” 45CC CHAIN SAW... 32
EMISSION CONTROL SYSTEM
WARRANTY .............................. 34
Page 3For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
SAVE THIS MANUAL
Keep this manual for the safety
warnings and precautions, assembly,
operating, inspection, maintenance and
cleaning procedures. Write the product’s
serial number in the back of the manual
near the assembly diagram (or month
and year of purchase if product has no
number). Keep this manual and the
receipt in a safe and dry place for future
reference.
IMPORTANT SAFETY
INFORMATION
In this manual, on the labeling,
and all other information
provided with this product:
This is the safety alert
symbol. It is used to alert
you to potential personal
injury hazards. Obey all
safety messages that
follow this symbol to avoid
possible injury or death.
DANGER indicates
a hazardous
situation which, if not
avoided, will result in death or
serious injury.
WARNING
indicates a
hazardous situation which, if
not avoided, could result in
death or serious injury.
CAUTION, used
with the safety
alert symbol, indicates a
hazardous situation which, if
not avoided, could result in
minor or moderate injury.
NOTICE is used to
address practices
not related to personal injury.
CAUTION, without
the safety alert
symbol, is used to address
practices not related to
personal injury.
General Power Tool Safety
Warnings
WARNING Read all safety
warnings and instructions.
Failure to follow the warnings and
instructions may result in electric
shock, re and/or serious injury.
Save all warnings and
instructions for future reference.
Keep Work Area Clean.1.
Cluttered areas invite injuries.a.
Do not start cutting until you haveb.
a clear work area, secure footing,
and a planned retreat path from the
falling tree.
Consider Work Area Environment.2.
Use extreme caution when cuttinga.
small size brush and saplings
because the slender material may
catch the saw chain and be whipped
toward you or pull you off balance.
Do not operate a chain saw in a treeb.
When cutting a limb that is underc.
tension be alert for spring back so
that you will not be struck when
released.
Page 4 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Keep Children Away.3.
All children and visitors should be
kept away from the chain saw and
the work area.
Store Idle Chain Saw.4.
When not in use, chain saws shoulda.
be stored in a dry, and high or
locked-up place – out of the reach of
children.
When storing saw, use a scabbardb.
or carrying case.
Don’t Force Chain Saw5.
It will do the job better and safer at
the rate for which it was intended.
Use Right Tool.6.
Cut wood only.a.
Don’t use chain saw for purposeb.
not intended – for example – Don’t
use chain saw for cutting plastic,
masonry, non-wood building
materials.
Dress properly.7.
Do not wear loose clothing ora.
jewelry. They can get caught in
moving parts. Rubber gloves and
non-skid footwear are recommended
when working outdoors.
Wear protective hair covering tob.
contain long hair.
Use ANSI-approved Safety8.
Glasses.
clothing; protective gloves; steel-toed
boots; hearing and head protection.
Carrying Saw.9.
Carry the chain saw by the front
off the switch, the guide bar and saw
chain to the rear.
Maintain Chain Saw With Care.10.
Keep tools sharp and clean for bettera.
and safer performance.
Follow instructions for lubricatingb.
and changing accessories.
Keep handles dry, clean, and freec.
from oil and grease.
Shut off Chain Saw.11.
Shut off chain saw when not in use,
before servicing, and when changing
accessories and attachments, such
as saw chain and guard.
Stay Alert.12.
Watch what you are doing. Usea.
common sense. Do not operate
chain saw when you are tired.
Keep all parts of the body away fromb.
the saw chain when the motor is
operating.
Before you start the saw, makec.
sure the saw chain is not contacting
anything.
Check Damaged Parts.13.
Before further use of the chaina.
saw, a guard or other part that
is damaged should be carefully
checked to determine that it will
operate properly and perform
its intended function. Check for
alignment of moving parts, binding
of moving parts, breakage of parts,
mounting, and any other conditions
that may affect its operation. A guard
or other part that is damaged should
be properly repaired or replaced by
an authorized service center unless
otherwise indicated elsewhere in this
instruction manual.
Have defective switches replaced byb.
authorized service center.
REV 09j
Page 5For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
Do not use chain saw if switch doesc.
not turn it off.
Do not operate a chain saw thatd.
is damaged, improperly adjusted,
or is not completely and securely
assembled. Be sure that the saw
chain stops moving when the trigger
is released.
Guard Against Kickback.14.
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 lose control of the saw which
could result in serious injury to the
user.
The following precautions should
be followed to minimize kickback:
Grip Saw Firmly.a.
hands when the motor is running.
handles.
Do not over reach.b.
Keep proper footing and balance atc.
all times.
Don’t let the nose of the guide bard.
contact a log, branch, ground or
other obstruction.
Don’t cut above shoulder height.e.
Use devices such as low kickbackf.
chain, guide bar nose guards, chain
brakes and special guide bars that
reduce the risks associated with
kickback.
Only use replacement bars andg.
or the equivalent.
Do not touch Guide Bar Nose15.
to any object. Tip contact may
cause guide bar to move suddenly
upward and backwards.
Use only identical Oregon16. ®Chain
and bar replacement components.
Inspect before every use; do not17.
use if parts are loose, missing, or
damaged.
DANGER!18. People with pacemakers
should not use chain saws. Chain
saws produce strong electromagnetic
interference or pacemaker failure.
People with pacemakers should
consult their physician(s) for advice.
CARBON MONOXIDE HAZARD19.
Using an engine indoors CAN KILL
YOU IN MINUTES.
Engine exhaust contains carbon
monoxide. This is a poison you
cannot see or smell.
NEVER use inside a home or garage,
EVEN IF doors and windows are
open.
Page 6 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Only use OUTSIDE and far away
from windows, doors, and vents.
Gasoline fuel and fumes are20.
Use proper fuel storage and handling
procedures. Do not store fuel or
21.
extinguishers nearby.
Operation of this equipment may22.
around dry vegetation.
A spark arrestor may be required.
The operator should contact
requirements.
Use only oil and fuel recommended23.
manual.
Do not operate in explosive24.
atmospheres, such as in the
or dust. Gasoline-powered engines
may ignite the dust or fumes.
Do not cover the engine or equipment25.
during operation.
Do not operate the equipment with26.
known leaks in the engine’s fuel
system.
When spills of fuel or oil occur, they27.
must be cleaned up immediately.
materials as per any local, state,
or federal codes and regulations.
Store oil rags in a bottom-ventilated,
covered, metal container.
Keep hands and feet away from28.
moving parts. Do not reach over or
across equipment while operating.
Before use, check for misalignment29.
or binding of moving parts, breakage
of parts, and any other condition
that may affect the equipment’s
operation. If damaged, have the
equipment serviced before using.
Many accidents are caused by poorly
maintained equipment.
Maintain labels and nameplates on30.
the tool. These carry important safety
information. If unreadable or missing,
contact Harbor Freight Tools for a
replacement.
Avoid unintentional starting. Prepare31.
to begin work before turning on the
tool.
Do not lay the tool down until it has32.
come to a complete stop. Moving
parts can grab the surface and pull
the tool out of your control.
This product is not a toy. Keep it out33.
of reach of children.
WARNING: Some dust created by34.
power sanding, sawing, grinding,
drilling, and other construction
activities, contains chemicals
known [to the State of California] to
cause cancer, birth defects or other
reproductive harm. Some examples
of these chemicals are:
cement or other masonry products
chemically treated lumber
Page 7For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
Your risk from these exposures
varies, depending on how often you
do this type of work. To reduce your
exposure to these chemicals: work in
a well ventilated area, and work with
approved safety equipment, such as
those dust masks that are specially
particles. (California Health & Safety
Code § 25249.5, et seq.)
This product contains or, when
used, produces a chemical known
to the State of California to cause
cancer and birth defects or other
reproductive harm. (California Health
& Safety Code § 25249.5, et seq.)
The warnings, precautions,35.
and instructions discussed in
this instruction manual cannot
cover all possible conditions and
situations that may occur. It must
be understood by the operator that
common sense and caution are
factors which cannot be built into this
product, but must be supplied by the
operator.
Vibration Safety
This tool vibrates during use.
Repeated or long-term exposure to
vibration may cause temporary or
permanent physical injury, particularly
to the hands, arms and shoulders. To
reduce the risk of vibration-related
injury:
Anyone using vibrating tools regularly1.
or for an extended period should
then have regular medical check-
ups to ensure medical problems are
not being caused or worsened from
use. Pregnant women or people
who have impaired blood circulation
to the hand, past hand injuries,
nervous system disorders, diabetes,
or Raynaud’s Disease should not use
this tool. If you feel any symptoms
related to vibration (such as tingling,
seek medical advice as soon as
possible.
Do not smoke during use. Nicotine2.
reduces the blood supply to the
of vibration-related injury.
Wear suitable gloves to reduce the3.
vibration effects on the user.
Use tools with the lowest vibration4.
when there is a choice.
Include vibration-free periods each5.
day of work.
Grip tool as lightly as possible (while6.
the tool do the work.
To reduce vibration, maintain the tool7.
as explained in this manual. If any
abnormal vibration occurs, stop use
immediately.
SAVE THESE
INSTRUCTIONS.
Page 8 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
SKU 66908 16” 37cc
Engine
Type 2 Stroke, air cooled
Rating 1.6 horsepower
Start Recoil
Compression 150 PSI
Displacement 37.2 cc
114 dB @ 3 ft.
Fuel
Type 90+octane unleaded
gasoline/2-cycle oil
Fuel/Oil
Ratio 40:1
Capacity 10.5 oz.
Chain Oil Type Chain & Bar Oil
Capacity 7 oz.
Spark Plug Type
Champion RCJ-7Y
Gap
Speed Idle 3,400 RPM
12,500 RPM
Cutting
Attachment
® Bar:
Model # 6G 516480 91 Sprocket
nose
and
Oregon® Chain:
Anti-Kickback standard skip
chain
# of drive links: 57
Model #91P057X
sharpening)
The emission control system for
these Chain Saw’s Engine is warranted for
standards set by the U.S. Environmental
Protection Agency. For warranty
information, refer to the last pages of this
manual.
SKU 66909 18” 45cc
Engine
Type 2 Stroke, air cooled
Rating 2.4 horsepower
Start Recoil
Compression 150 PSI
Displacement 45 cc
114 dB @ 3 ft.
Fuel
Type 90+octane unleaded
gasoline/2-cycle oil
Fuel/Oil
Ratio 40:1
Capacity 18.6 oz.
Chain Oil Type Chain & Bar Oil
Capacity 8.5 oz.
Spark Plug Type
Champion RCJ-7Y
Gap
Speed Idle 3,400 RPM
12,500 RPM
Cutting Attachment
® Bar:
Model # NG 516481 .325
Sprocket nose
and
Oregon® Chain:
Anti-Kickback standard
skip chain
# of drive links: 72
Model #21BPX072X
UNPACKING
When unpacking, make sure that the
item is intact and undamaged. If any parts
are missing or broken, please call Harbor
Freight Tools at 1-800-444-3353 as soon
as possible.
SPECIFICATIONS
REV 09f
Page 9For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
THIS PAGE INTENTIONALLY LEFT BLANK.
Page 10 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Figure 1 - Model 66908 16” 37cc Chain Saw
Figure 2 - Model 66909 18” 45cc Chain Saw
CHAIN SAW COMPONENTS
Chain Brake
Chain Brake
Power Switch
Chain & Bar Oil Cap
Guide
Bar
Nose
Guide Bar
Prime Valve
Saw Chain
Access to
Spark Plug &
Air Filter
Access to
Spark Plug &
Air Filter
Choke
Starter
Cord
Starter Cord
Throttle Trigger
Rear
Handle
Fuel Cap
Bucking Spike
Chain Brake
Chain Brake
Power Switch
Fuel Cap
Chain & Bar Oil Cap
Guide
Bar
Nose
Guide Bar
Saw Chain
Access to
Spark Plug &
Air Filter
Access to
Spark Plug
& Air Filter
Choke
Starter
Cord
Starter Cord
Throttle Trigger
Rear
Handle
Bucking
Spike
REV 09j
Page 11For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
MAIN CONTROLS
1.
hand on the Rear Handle, when the
Chain Saw is running.
Guide Bar: The Guide Bar supports2.
and guides the Saw Chain.
Saw Chain: The Saw Chain is a loop3.
of chain with cutting teeth that cut the
wood. It is driven by the Motor. When
low-kickback saw chains.
Throttle Trigger: The Throttle Trigger4.
engages the Saw Chain once the
engine is running.
5.
operation of the Throttle Trigger.
6.
Chain Saw suddenly rotates up and
back towards you, your hand holding
engaging the brake and stopping the
Saw Chain.
OPERATING INSTRUCTIONS
Read the ENTIRE IMPORTANT
SAFETY INFORMATION
section at the beginning of this
manual including all text under
subheadings therein before set
up or use of this product.
Tool Set Up
TO PREVENT
SERIOUS INJURY
FROM ACCIDENTAL
OPERATION:
Stop the engine, turn the
Power Switch off, and allow
the tool to stop and cool
completely before adjusting
the tool or installing
accessories.
Saw Chain Tension
The Chain Saw is fully assembled,
but may require a minor adjustment
to the Saw Chain tension. Before
using, check the Saw Chain tension.
Note: New Saw Chains often need to
be tensioned several times during
While wearing heavy duty gloves,
carefully grab the Saw Chain in the
middle section under the Guide Bar.
Pull the Saw Chain away from the
Guide Bar. The Saw Chain should
snap back against the Guide Bar. The
of the Chain Bar, yet you should still
be able to slide the chain along the
Chain Bar by hand. There should be
no sagging between the Guide Bar
and Saw Chain on the underside of
the Guide Bar.
REV 09j
Page 12 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Figure 2
Guide
Bar
Saw
Chain
Chain Tension Screw
(On Model 66909)
Chain Tension
Screw
(On Model
66908)
Nuts
covering
Mounting
Bolts
Drive Cover
If the Saw Chain needs adjustment:
1.
Bolts on the Drive Cover.
Pull up on the Guide Bar Nose and2.
hold it up while making the tension
adjustment.
Turn the Chain Tension Screw3.
clockwise to apply more Saw Chain
tension, until the Saw Chain makes
contact along the bottom of the Chain
Bar. Turn the Tension Screw 1/4 turn
more.
Continue to hold the Guide Bar Nose4.
up while tightening the Nut on the
rear Mounting Bolt. Then tighten the
remaining Nut.
After this adjustment is made, check
the Saw Chain tension again by
pulling the Saw Chain away from the
top of the Guide Bar, then making
sure that it can slide along the Guide
Bar. Also, test the tension by pulling
the Saw Chain away from the bottom
of the Guide Bar, then letting it go.
The Saw Chain should snap back
into place in the groove of the Guide
Bar. Repeat the above adjusting
steps if needed to achieve the correct
tension.
Adding and/or Changing Chain Oil
Check the Chain & Bar Oil level
before each use of the Chain Saw
unthread the Chain & Bar Oil Cap
Cap opening. Replace and securely
close the Cap.
Filling the Fuel Tank
WARNING! TO PREVENT
SERIOUS INJURY FROM
FIRE:
the fuel tank in a well-ventilated area
away from ignition sources. Do not
smoke.
WARNING! Your Warranty is
voided if: You do not operate
the Chain Saw with the proper
40:1 fuel mix in its Fuel Tank.
Never run the Engine with an
improper fuel mix, low or no fuel
mix. Running the Engine with an
improper fuel mix, low or no fuel
mix will permanently damage the
unit. Only use 2-stroke engine oil
for air cooled engines. Never use
outboard engine oil.
To obtain the proper 40:1 fuel mix,1.
combine 2 stroke engine oil with
unleaded gasoline (minimum 90
octane rating) in a clean, approved
container. To mix the fuel:
Add half the amount of fuel and thea.
entire amount of oil.
Cover and gently shake the fuelb.
mixture.
Add the remaining amount of fuel.c.
Cover and gently shake to thoroughly2.
mix before each fueling. Refer to the
REV 09j
Page 13For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
Chart below for proper mix quantities.
NOTE: Mix only enough fuel for
a few days work. The maximum
storage time of mixed fuel is 3
months.
FUEL MIX QUANTITIES
Ratio 2 Stroke
Engine Oil
Unleaded Gasoline
(90 Octane)
40:1 3.2 Fl. Oz. 1 Gal.
40:1 6.4 Fl. Oz. 2 Gal.
Figure 3
3. Once the proper fuel mix is obtained,
wipe gas cap and its surrounding
area, then remove the Gas Cap. Fill
the Fuel Tank up to the lip of the
opening with the fuel mix. Then,
securely replace the Gas Cap.
Note: Inspect the Fuel Cap O-Ring each
cracked, cut or leaking.
General Operating Instructions
Before starting the Chain Saw
Add Chain & Bar oil (not included)1.
and the Gas/oil mixture (not
included).
Check the Saw Chain Tension and2.
adjust if necessary (See Tool Set Up).
Be ready to cut before starting the3.
Chain Saw. Stand in front of the wood
4.
will know how to turn off the engine
immediately if needed.
Place the Chain Saw on the ground5.
while starting the engine.
WARNING!: Do not start the engine
while holding the chain saw above
the ground. You may loose control
when the engine starts up and cause
Starting Procedure with the Chain
Saw placed on the ground.
Starting Procedure
For Model 66908 only, push the6.
Prime Valve 5 times.
Pull out the Choke.7.
Place your foot on the bottom of the8.
Rear Handle to hold the Chain Saw
starting the engine.
Pull the Starter Cord 4 or 5 short pulls9.
to get gas and air in the engine.
Turn on the Power Switch.10.
Push the Choke half way in.11.
Pull the Starter Cord quickly and12.
starts.
Push the Choke all the way in.13.
REV 09j
Page 14 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Operating the Chain Saw
Note: Front Handle Guard not
shown in illustration
Figure 4
1. Grasp the front and rear Handles with
both hands. Always grip the handle
the handle as show above.
Take your foot off the rear handle and2.
lift the Chain Saw to work level.
DANGER! To prevent serious injury and
death from kickback: Do not touch
the tip of the Guide Bar to any object.
3.
squeeze the Throttle Trigger to
engage the Saw.
When the Chain Saw reaches full4.
speed, begin cutting with a light,
downward pressure against the
bottom-center section of the Saw
Chain. Allow the Saw Chain to cut
at its own rate. Applying too much
pressure can damage the tool.
WARNING! When cutting loose, round,
wood stock, make sure to place the
wood stock in a sawhorse, cradle
or use a timberjack (not included) to
avoid grabbing and throw back.
5.
and turn off the Power Switch.
Wait for the Saw to come to a6.
complete stop before laying it down.
When the Saw is cooled completely,7.
cover the Guide Bar with the Guide
Bar Sheath.
After use, to prevent accidents, turn8.
off the engine, wait for the engine
to cool, then disconnect its spark
plug wire after use. Clean external
parts with clean cloth, then store the
equipment out of children’s reach
according to the Storage instructions
in this manual.
Basic Felling, Limbing, and
Bucking Cut Techniques
Felling
When1. felling a tree, make sure the
tree is not felled in a manner that
would endanger any person, strike
any utility line, or cause any property
damage. Before felling is started,
consider the natural lean of the tree,
the location of larger branches, and
the wind direction, to judge which
way the tree will fall. The Chain Saw
operator should keep on the uphill
side of the terrain, as the tree will
likely roll or slide downhill after it is
felled.
REV 09j
Page 15For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
2.
Figure 5
A retreat path should be planned and
cleared as necessary before cuts
are started. The retreat path should
extend back and diagonally to the
rear of the expected line of fall.
Make sure to remove dirt, stones,3.
loose bark, nails, staples, wire, and
other foreign objects from the tree
where the cuts are to be made.
Figure 6
4. When making a notching undercut,
make the notch 1/3 the diameter
of the tree, perpendicular to the
direction of the fall. Make the lower
help to avoid pinching of either the
Saw Chain or the Guide Bar when
the second notch is being made.
When making a5. felling back cut,
make the felling back cut at least
2 inches higher than the horizontal
notching cut. Keep the felling back
cut parallel to the horizontal notching
cut. Make the felling back cut so
enough wood is left to act as a hinge.
The hinge wood keeps the tree from
twisting and falling in the wrong
direction. Do not cut through the
hinge.
As the felling cut gets close to the6.
hinge the tree should begin to fall.
If there is any chance that the tree
may not fall in the desired direction,
or it may rock back and bind the Saw
Chain, stop cutting before the felling
back cut is complete and use wedges
of wood, plastic, or aluminum to open
the cut and drop the tree along the
desired line of fall.
When the tree begins to fall, remove7.
the Chain Saw from the cut. Turn
off the Chain Saw and put the Chain
Saw down. Then, use the retreat
path planned. Be alert for overhead
limbs falling, and watch your footing.
Page 16 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Limbing
.
Figure 7
8. When limbing (trimming) branches
from a fallen tree, leave the larger,
lower limbs to support the log off
the ground. Remove the small limbs
in one cut. Branches under tension
should be cut from the bottom up to
avoid binding the Saw Chain.
Bucking
Bucking9. a log is cutting a log into
lengths. It is important to make sure
is evenly distributed on both feet.
When possible, the log should be
raised and supported by the use of
limbs, logs, chocks or a timberjack.
Figure 8
10. To Overbuck is when the log is
supported along its entire length and
is cut from the top. Allow the Saw to
pull forward into the top of the log
until the Bucking Spike catches on
the log. Then pivot the saw through
the log.
Figure 9
11. To Underbuck is when the log is
supported on one end, and a cut 1/3
the diameter of the log is made from
the underside of the log. Then, the
Figure 10
12. When the log is supported on both
ends, cut 1/3 of the log’s diameter
from the top overbuck. Then, make
lower 2/3 diameter of the log to meet
Page 17For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
Figure 11
13. When bucking on a slope, always
stand on the uphill side of the log.
complete control release the cutting
pressure near the end of the cut
without relaxing your grip on the
Chain Saw Handles. Do not allow
the Saw Chain to contact the ground.
After completing the cut, wait for the
Saw Chain to stop before moving the
Chain Saw. Always turn off the Chain
Saw before moving from tree to tree.
MAINTENANCE AND
SERVICING
Proceduresnotspecically
explained in this manual
must be performed only by a
qualiedtechnician.
TO PREVENT
SERIOUS INJURY
FROM ACCIDENTAL
OPERATION:
Turn the Power Switch of the
tool off before performing any
inspection, maintenance, or
cleaning procedures.
TO PREVENT SERIOUS
INJURY FROM TOOL
FAILURE:
Do not use damaged
equipment. If abnormal noise
or vibration occurs, have the
problem corrected before
further use.
Cleaning, Maintenance, and
Lubrication
BEFORE EACH USE,1. inspect the
general condition of the tool. Check
for loose hardware, misalignment or
binding of moving parts, cracked or
broken parts, dull or damaged Saw
Chain, and any other condition that
may affect its safe operation.
Check that the Chain Brake and2.
technician if the there are any doubts
or problems with the safety features.
BEFORE THE FIRST USE,3. apply
Chain & Bar oil (not included) to
the Saw Chain. Oil is automatically
applied to the Saw Chain when the
Oil Reservoir is full.
IF THE SAW CHAIN BECOMES4.
LOOSE, adjust the saw chain tension
as described under Tool Setup.
WHEN NECESSARY,5. sharpen the
Saw Chain, or have it sharpened by a
PERIODICALLY,6. turn the Guide
Bar over to distribute the wear on it.
Replace the Guide Bar when bent,
cracked, or when the Saw Chain
moves excessively from side to side
on the Guide Bar.
REV 09j
Page 18 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
AFTER USE,7. wipe with a clean,
dry cloth. If necessary use a mild
detergent. Do not use solvents. Do
not immerse this tool in liquid.
Guide Bar Care
Remove the Guide Bar after use to
clean and grease.
Remove sawdust from the Bar
Groove using a Guide Bar Cleaning
tool (sold separately), then grease
the Nose Sprocket at the Grease Port
with a grease gun (sold separately).
Reverse the Guide Bar when
replacing the Saw Chain to prevent
uneven wear.
should always be parallel to each
other. To check the Guide Bar:
Straight
Guide
Bar
Ruler
Saw
Chain
Gap
Figure 12
Place a ruler along the surface of the
Guide Bar and Saw Chain. If there is
a gap, the bar is normal.
I
Ruler
Bent
Guide
Bar
Tilting
Saw
Chain
Figure 13
and Saw Chain, or the Chain tilts to
one side, then the Bar is bent and
needs to be replaced.
Sharpening the Saw Chain
For smooth and safe operation,
always keep the Saw Chain cutters
sharp.
The cutters need to be sharpened
when:
The sawdust becomes powder-like.a.
You can’t make the cut without extrab.
force.
The Chain Saw does not cut straight.c.
Vibration increases.d.
Warning: Be sure to wear safety gloves
when handling the Saw Chain.
Follow the Saw Chain manufacturer’s
instructions for sharpening the Saw
Chain.
Replacing the Saw Chain
WARNING! Do not attempt to install a
Saw Chain or Guide Bar other than
the size and type provided and
listedintheSpecicationsChart.
REV 09j
Page 19For technical questions, please call 1-800-444-3353.
SKU 66908 / 66909
Mounting
Bolts
Chain Saw Sprocket
(Behind Sprocket
Assembly)
Guide
Bar Saw
Chain
Mounting
Bolt Holes
Chain Tension Screw
(On Model 66909)
Chain Tension
Screw
(On Model
66908)
Nuts
Nuts
Drive Cover
Drive Cover
Figure 14
1. Soak the new Saw Chain overnight in
Chain & Bar oil (sold separately).
Disengage the Chain Brake by pulling2.
3.
Chain by turning the Chain Tension
Screw counter clockwise until the
Saw Chain is loose.
Remove the Drive Cover by4.
unthreading the two Nuts from the
Mounting Bolts.
For Model # 66908 only, disengage5.
the Tensioning Pin (connected to
the Tensioning Screw) by tilting the
bottom of the Guide Bar up and away
from the Chain Saw before step 6.
Push the Guide Bar toward the6.
Sprocket to further loosen the Saw
Chain.
Remove the Saw Chain from the7.
Sprocket then the Guide Bar.
Note: Always check the condition of the
Sprocket when replacing the chain.
The Sprocket should be replaced if it
shows signs of wear or is damaged. If
needed, have the sprocket replaced
and the bearings greased by a
Flip the Guide Bar over before8.
mounting the new Saw Chain. This
will ensure that the Guide Bar wears
evenly over time. (For Model # 66908
only, line up the Tensioning Pin with
the Guide bar in place).
Direction of Saw
Chain Cutters
Saw
Guide
Bar
Nose
Figure 15
9. Place the new Saw Chain around the
Sprocket, then over the Guide Bar.
Make sure the Cutters of the Saw
Chain are facing away from the Chain
Saw along the top edge of the Guide
Bar. Fit the chain in the groove all
around the Guide Bar.
Replace the Drive Cover, being10.
careful to line up the Mounting Bolts
with the Mounting Bolt holes.
REV 09j
Page 20 For technical questions, please call 1-800-444-3353. SKU 66908 / 66909
Finger tighten the Nuts, then tension11.
the Saw Chain following the steps in
the Set Up section “Tensioning the
Cylinder Fins
prevent clogging which can cause the
engine to overheat.
Air Filter Maintenance
To clean the Air Filter:
Wipe the top of the Air Filter cover,1.
untrhead the Knob holding the cover
in place, and remove the cover.
Remove the Air Filter.2.
3.
and replace if damaged.
If undamaged, use a clean cloth to4.
wipe the Air Filter clean of dust and
debris.
Caution: Do not use compressed air to
Replace the Air Filter and Cover and5.
secure the Knob in place.
Spark Plug Maintenance
Wipe the Air Filter cover, unthread the1.
Knob holding the cover in place, and
remove the cover.
Disconnect the spark plug wire from2.
the end of the plug. Clean out debris
from around the spark plug.
Using a spark plug wrench, remove3.
the spark plug.
Inspect the spark plug:4.
If the electrode is oily, clean it usinga.
a clean, dry rag.
If the electrode has deposits on it,b.
clean with a wire brush.
If the white insulator is cracked orc.
chipped, the spark plug needs to be
replaced.
When installing a new spark plug,5.
electrode or the insulator, the spark
plug can be damaged.
Install the new spark plug or the6.
cleaned spark plug into the engine.
Gasket-style: Finger-tighten until the
gasket contacts the cylinder head,
then about 1/2-2/3 turn more.
Non-gasket-style: Finger-tighten until
the plug contacts the head, then
about 1/16 turn more.
Apply dielectric spark plug boot7.
protector (not included) to the end of
the spark plug and reattach the wire
securely.
Fuel Filter Replacement
WARNING! TO PREVENT
SERIOUS INJURY FROM
FIRE:
REV 09j
This manual suits for next models
1
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