Read all safety rules and instructions carefully before operating this tool.
Owner’s Manual
TOLL-FREE HELPLINE: 1-855-345-3934
www.GreenWorksTools.com
80V Brushless String Trimmer
GST80321
2
CONTENTS
Introduction ..........................................................................................................................2
Important Safety Instructions ...............................................................................................3
Symbols ...............................................................................................................................6
Know Your String Trimmer ................................................................................................... 8
Assembly ............................................................................................................................. 9
Operation ........................................................................................................................... 12
Maintenance............................................................................................................................17
Troubleshooting..................................................................................................................18
Warranty...................................................................................................................19
Exploded View and Part List ................................................................................................20
PRODUCT SPECIf ICATIONS
80V BRUSHLESS STRINg TRImmER
Type ............................................................................................. Cordless, battery-powered
Motor ..............................................................................................................................80 V
String Cutting Width .....................................................................................................14-16 in.
String Diameter ..............................................................................................0.080" (2.03 mm)
Speed ..............................................................................................................5000/5500 RPM
Weight (without battery) ................................................................................................10.6 lbs
Weight (with 2Ah battery) ..............................................................................................13.8 lbs
Battery pack .................................................................................................................2901302
Charger ........................................................................................................................2901402
3
IMPORTANT SAf ETY INSTRUCTIONS
WARNINg
Read and understand all instructions before using this product. f ailure to follow all
instructions listed below may result in electric shock, re, and/or serious personal injury.
• Do not operate power tools in explosive atmospheres, such as in the presece of ammable
liquids, gases, or dust. Power tools create sparks which may ignite the dust or fumes.
• Do not allow children or untrained individuals to use this unit.
• Don’t expose power tools to rain or wet conditions. Water entering a power tool will increase
the risk of electric shock.
• Do not handle plug or tool with wet hands.
• Never allow children to operate the equipment. Never allow adults to operate the equipment
without proper instruction.
• Always wear safety glasses with side shields marked to comply with ANSI Z87.1. Everyday
glasses have only impact resistant lenses. They are NOT safety glasses. f ollowing this rule
will reduce the risk of eye injury. Use face mask if operation is dusty.
• Secure long hair above shoulder level to prevent entanglement in moving parts.
• Do not expose to rain, store indoors.
• Do not operate in poor lighting.
• Keep all parts of your body away from any moving part
• keep hair, loose clothing, ngers and all body parts away from openings and moving parts.
• Wear heavy long pants, boots, and gloves. Avoid loose garments or jewelry that could get
caught in moving parts of the machine or its motor.
• Do not force tool. Use the correct tool for your application. The correct tool will do the job
better and safer at the rate for which it is designed.
• Do not operate the equipment while barefoot or when wearing sandals or similar lightweight
footwear. Wear protective footwear that will protect your feet and improve your footing on
slippery surfaces.
• Secure long hair so it is above shoulder level to prevent entanglement in any moving parts.
• Keep rm footing and balance. Do not overreach. Overreaching can result in loss of balance.
• Do not allow to be used as a toy. Close attention is necessary when used by or near children.
• Do not use tool if switch does not turn it on or off. Any tool that cannot be controlled with the
switch is dangerous and must be repaired.
• Keep all bystanders, children, and pets at least 50 ft. away
• Do not operate this unit when you are tired, ill or under the influence of alcohol, drugs or
medication.
• Keep all parts of your body away from any moving parts and all hot surfaces of the unit.
• Do not put any object into openings. Do not use with any opening blocked; keep openings free
of dust, lint, hair, and anything that may reduce air ow.
4
IMPORTANT SAf ETY INSTRUCTIONS
• Check the work area before each use. Remove all objects such as rocks, broken glass, nails,
wire, or string which can be thrown or become entangled in the machine.
• Use only identical manufacturer’s replacement parts and accessories. Use of any other parts
may create a hazard or cause product damage.
• Do not charge battery tool in rain, or damp or wet location. f ollowing this rule will reduce the
risk of electric shock.
• f or household use only.
• Battery tools do not have to be plugged into an electrical outlet; therefore, they are always in
operating condition. Be aware of possible hazards when not using your battery tool or when
changing accessories. Following this rule will reduce the risk of electric shock, re, or serious
personal injury.
• Remove or disconnect battery before servicing, cleaning or removing material from the
gardening appliance.
• Use only Greenworks 80-volt batteries.
• Store idle appliances - When not in use, string trimmer should be stored indoors in a dry,
locked place out of the reach of children.
• Do not dispose of the batteries in a re. The cells may explode. Check with local codes for
possible special disposal instructions.
• Do not open or mutilate the batteries. Released electrolyte is corrosive and may cause
damage to the eyes or skin. It may be toxic if swallowed.
• Do not place battery tools or their batteries near fire or heat. This will reduce the risk of
explosion and possible injury.
• Batteries can explode in the presence of a source of ignition, such as a pilot light. To reduce
the risk of serious personal injury, never use any cordless product in the presence of open
flame. An exploded battery can propel debris and chemicals. If exposed, flush with water
immediately.
• Do not crush, drop or damage battery pack. Do not use a battery pack or charger that has
been dropped or received a sharp blow. A damaged battery is subject to explosion. Properly
dispose of a dropped or damaged battery immediately.
• Exercise care in handling batteries in order not to short the battery with conducting materials
such as rings, bracelets, and keys. The battery or conductor may overheat and cause burns.
• f or best results, your battery tool should be charged in a location where the temperature is
more than 50°F but less than 100°F. To reduce the risk of serious personal injury, do not store
outside or in vehicles.
• Under extreme usage or temperature conditions, battery leakage may occur. If liquid comes in
contact with your skin, wash immediately with soap and water, then neutralize with lemon juice
or vinegar. If liquid gets into your eyes, ush them with clean water for at least 10 minutes,
then seek immediate medical attention. f ollowing this rule will reduce the risk of serious
personal injury.
• If the power supply cord is damaged, it must be replaced only by the manufacturer or by an
authorized service center to avoid risk.
• Do not point the string trimmer in the direction of people or pets.
5
• When not in use, string trimmer should be stored indoors in a dry, locked up place—out of the
reach of children.
• Maintain tool with care. Keep vents clean for best and safest performance. f ollow instructions
for proper maintenance. Do not attempt to clear clogs from tool without rst disconnecting the
battery.
• To reduce the risk of electrical shock, do not expose to rain, do not use on wet surfaces. Store
indoors.
• Save these instructions. Refer to them frequently and use them to instruct others who may
use this power tool. If you loan someone this power tool, loan them these instructions also.
CHILD SAFETY
Tragic accidents can occur if the operator is not aware of the presence of children.
• Keep children out of the working area and under the watchful care of a responsible adult.
• Do not allow children under the age of 14 to operate this trimmer. Children who are 14
years of age and older must read and understand the operating instructions and safety
rules in this manual and must be trained and supervised by a parent.
• Stay alert, and turn the trimmer off if a child or any other person enters the working area.
• Look behind and down for small children before and while cutting backwards.
• Use extreme care when approaching blind corners, doorways, shrubs, trees, or other
objects that may obscure your view of a child who may run into the path of the trimmer.
W A R N I N g (PROPOSITION 65)
Some dust created by power sanding, sawing, grinding, drilling, and other construction activities
contains chemicals known to cause cancer, birth defects or other reproductive harm. Some
examples of these chemicals are:
• Lead from lead-based paints
• Crystalline silica from bricks and cement and other masonry products, and
• Arsenic and chromium from chemically treated lumber.
Your risk of exposure to these chemicals 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 dust masks that are specially designed to lter out microscopic
particles.
IMPORTANT SAf ETY INSTRUCTIONS
6
Some of the following symbols may be used on this product. Please study them and learn their
meaning. Proper interpretation of these symbols will allow you to operate the product better and safer.
SYmBOL NAmE DESIgNATION/EXPLANATION
V Volts Voltage
A Amperes Current
Hz Hertz frequency (cycles per second)
W Watts Power
min Minutes Time
Alternating Current Type of current
Direct Current Type or a characteristic of current
No Blade Do not install or use any type of blade on a
product or displaying this symbol.
/min Per Minute Revolutions, strokes, surface speed, orbits
etc., per minute.
Wet Conditions Alert Do not expose to rain or use in damp locations.
Read The Operator’s Manual To reduce the risk of injury user must read and
understand operator’s manual before using
this product.
Eye Protection Always wear eye protection with side shields
marked to comply with ANSI Z87.1 when
operating this equipment.
Safety Alert Precautions that involve your safety.
Ricochet Thrown objects can ricochet and result in
personal injury or property damage.
Keep Bystanders Away Keep all bystanders at least 50 ft. away.
Class II Construction Double-insulated construction
SYMBOLS
The following signal words and meanings are intended to explain the levels of risk associated
with this product.
SERVICE
Servicing requires extreme care and knowledge and should be performed only by a qualified
service technician. for service we suggest you return the product to your nearest AUTHORIZED
SERVICE CENTER for repair. When servicing, use only identical replacement parts.
WARNINg
To avoid serious personal injury, do not attempt to use this product until you have read this Owner's
Manual thoroughly and understand it completely. If you do not understand the warnings and
instructions in this Owner's Manual, do not use this product. Call the Toll-free Helpline (1-855-345-
3934) for assistance. The operation of any power tool can result in foreign objects being thrown
into your eyes, which can result in severe eye damage. Before operating a power tool, always wear
safety goggles, safety glasses with side shields, or a full face shield when needed. We recommend
a Wide Vision Safety Mask for use over eyeglasses or standard safety glasses with side shields.
Always use eye protection that is marked to comply with ANSI Z87.1.
WARNINg
The operation of any power tool can result in foreign objects being thrown into your eyes,
which can result in severe eye damage. Before beginning power tool operation, always
wear safety goggles or safety glasses with side shields and, when needed, a full face
shield. We recommend Wide Vision Safety Mask for use over eyeglasses or standard
safety glasses with side shields. Always use eye protection which is marked to comply
with ANSI Z87.1.
DANgER Indicates an imminently hazardous situation, which, if not
avoided, will result in death or serious injury.
WARNINg Indicates a potentially hazardous situation, which, if not avoided,
could result in death or serious injury.
CAUTION Indicates a potentially hazardous situation, which, if not avoided,
may result in minor or moderate injury.
CAUTION (Without Safety Alert Symbol) Indicates a situation that may
result in property damage.
SYMBOLS
SAVE THESE INSTRUCTIONS
7
SYmBOL SIgNAL mEANINg
8
KNOW YOUR STRING TRIMMER
AUXILIARY HANDLE
The string trimmer is equipped with an auxiliary handle for ease of operation and to prevent loss
of control.
gUARD
The trimmer includes a guard that helps protect you from ying debris.
KNOW YOUR STRINg TRImmER (See Figure 1.)
The safe use of this product requires an understanding of the information on the product and in
this operator’s manual as well as a knowledge of the project you are attempting. Before use of this
product, familiarize yourself with all operating features and safety rules.
Fig. 1
REAR HANDLE
HIgH/LOW SPEED
BUTTON
ON/OFF BUTTON
SWITCH TRIggER
AUXILIARY HANDLE
COUPLER
TRImmER SHAFT
gEAR HEAD
gUARD
TRImmER HEAD
LOCK-OUT BUTTON
9
ASSEMBLY
WARNINg
Do not use this product if any parts on the packing list are already assembled to your product when
you unpack it. Parts on this list are not assembled to the product by the manufacturer and require
customer installation. Use of a product that may have been improperly assembled could result in
serious personal injury.
PACKINg LIST
• Power head
• Auxiliary handle
• Straight shaft trimmer attachment
• Guard
• (4) Auxiliary handle screws
• Operator’s manual
WARNINg
If any parts are damaged or missing, do not operate this product until the parts are replaced. Use
of this product with damaged or missing parts could result in serious personal injury.
WARNINg
Do not attempt to modify this product or create accessories not recommended for use with this
blower. Any such alteration or modication is misuse and could result in a hazardous condition
leading to possible serious personal injury.
WARNINg
Do not connect to power supply until assembly is complete. failure to comply could result in
accidental starting and possible serious personal injury.
UNPACKINg
This product requires assembly.
• Carefully remove the product and any accessories from the box. Make sure that all items
listed in the packing list are included.
• Inspect the tool carefully to make sure no breakage or damage occurred during shipping.
• Do not discard the packing material until you have carefully inspected and satisfactorily
operated the tool.
• If any parts are damaged or missing, please call 1-855-345-3934 .
ASSEMBLY
10
INSTALLINg AN ATTACHmENT TO THE POWER HEAD (See Figure 3.)
WARNINg
Read and understand entire Operator’s Manual for each optional attachment used on this power
head and follow all warnings and instructions. failure to follow all instructions may result in electric
shock, re and/or serious personal injury.
WARNINg
Never install, remove, or adjust any attachment while power head is running. Failure to stop the
motor can cause serious personal injury. Never operate power head without an attachment.
Fig. 2
gUARD
SCREW
ATTACHINg THE gUARD (See Figure 2.)
NOTE: Install the guard before the attachment is connected to the power head.
• Invert the string trimmer to access the trimmer head.
• Using a Phillips head screwdriver (not included), remove the pre-installed screws from the
trimmer head.
• Place the guard on to the trimmer head and place the guard plate on the guard.
• Align the screw holes on the guard with the screw holes on the trimmer head.
• Insert the screws into the trimmer head, fastening the guard in place.
gUARD PLATE
ASSEMBLY
11
NOTE: When using string trimmer attachments, use only .080 in. diameter line.
The attachment connects to the power head by means of a coupler device.
• Loosen the attachment knob on the coupler.
• Push in the release button located on the attachment shaft. Align the button with the guide
recess on the power head coupler and slide the two shafts together. Rotate the attachment
shaft until the button locks into the positioning hole.
NOTE: If the button does not release completely in the positioning hole, the shafts are not locked
into place. Slightly rotate from side to side until the button is locked into place.
• Tighten the attachment knob securely.
REmOVINg THE ATTACHmENT FROm THE POWER HEAD
for removing or changing the attachment:
• Stop the power head.
• Remove the battery from the power head.
• Loosen the attachment knob.
• Push in the release button and twist the shafts to remove and seperate ends.
ATTACHINg THE FRONT HANDLE (See Figure 4.)
Fig. 4
Fig. 3
RELEASE BUTTON
POSITIONINg HOLE
ATTACHmENT KNOB
ATTACHmENT SHAFT
• Press the auxiliary handle onto the power head shaft so that the handle is angled toward the
rear handle that allows for comfortable operation.
• Slide the bolts through the holes in the auxiliary handle, and tighten them securely.
ASSEMBLY
ADJUSTINg THE CUTTINg SWATH (See Figure 5.)
The trimmer is currently set at a 14 in. cutting swath. To adjust to a cutting swath of 16 in.:
• Remove the battery from the string trimmer.
• Remove both screws on the cut-off blade with a Phillips screwdriver (not included).
• Rotate the cut-off blade 180°.
• Replace both screws in the cut-off blade.
Note: Set the cut-off blade to 14 in. for greater runtime. Set the cut-off blade to 16 in. for greater
cutting area.
CUT-OFF BLADE
ATTACHINg A SHOULDER HARNESS (See Figure 6.)
• Rotate the harness holder to the upward position.
• Hook a shoulder harness (not included) to the harness holder.
HARNESS HOLDER
Fig. 5
Fig. 6
12
13
OPERATION
WARNINg
Read and understand entire Operator's Manual for each optional attachment used on this power
head and follow all warnings and instructions. failure to follow all instructions may result in electric
shock, re and/or serious personal injury.
WARNINg
Do not allow familiarity with this product to make you careless. Remember that a careless fraction
of a second is sufcient to inict serious injury.
WARNINg
Do not use any attachments or accessories not recommended by the manufacturer of this product.
The use of attachments or accessories not recommended can result in serious personal injury.
WARNINg
This string trimmer is not meant to be used with brush cutter attachments. Use of a brush cutter
attachment could cause serious personal injuries or property damage.
14
OPERATION
OPERATINg THE TRImmER (See Figure 8.)
Hold the power head with your right hand on the rear handle and your left hand on the front
handle. Keep a rm grip with both hands while in operation. Power head should be held at a
comfortable position with the rear handle about hip height.
Always operate power head at full throttle. If debris becomes wrapped around the attachment,
release the switch trigger, and remove the debris.
Fig. 7
SWITCH TRIggER
LOCK-OUT BUTTON
HIgH SPEED BUTTON
POWER BUTTON
LOCK-OUT BUTTON (See Figure 7.)
The lock-out button reduces the possibility of accidental starting. The lock-out button is located
on the handle above the switch trigger. The lock-out button must be depressed before you pull
the switch trigger. The lock resets each time the trigger is released.
STARTINg AND STOPPINg THE TRImmER (See Figure 7.)
To start:
• Press the power button.
• Press high speed button to increase speed depending upon grass condition. Two LED's will
illuminate above the high speed button indicating that the trimmer is in the high speed setting.
• Depress the lock-out button and squeeze the switch trigger.
To stop:
• Release the switch trigger.
• Press the power button again to turn the unit off.
Note: The unit will power itself down after being idle for 1 minute.
15
OPERATION
WARNINg
Any contact with the attachment cutting head can result in burns and/or other serious personal
injury.
WARNINg
Extreme care must be taken when using a blade attachment to ensure safe operation. Read the
safety information for safe operation when using a blade attachment and refer to the safety rules
and instructions in your attachment manual. Never use a brush cutter attachment with this electric
power head. Improper operation of a blade or any attachment could result in serious injury.
Fig. 8
16
OPERATION
Fig. 10
INSTALLINg STRINg IN STRINg HEAD (See Figure 9.)
1. Line up the slots on the spool cap with the slots
on the string head.
2. Insert line through the string head hole. Push line
until it exits the opposite string head hole.
3. Pull the line through until there is an equal
amount of line on each side.
4. Turn the spool cap clock-wise to begin
winding the string into the string head. Leave
approximately 5 inches of string protruding out of
each side of the head.
It is recommended that .080” line Diameter be used
for this string head.
Note: Do not put more than 15 feet of line in at a time.
Spool Cap
String Head
String Head Hole
Slots
Fig. 9
REmOVINg / REPLACINg STRINg HEAD (See Figure 10.)
1. Line up the spacer hole up with the hole in the gear box.
2. Place a small screw driver or metal rod (Not included) in the spacer hole.
3. Rotate the head clockwise to loosen and remove.
4. Reverse steps 1.-3. to reinstall the same string head.
Note: If you put a different model string head on this unit please follow the manufacturer’s instructions to
install that head.
SPACER HOLE
mETAL ROD
17
OPERATION
Fig. 11
LINE TRImmINg CUT-OFF BLADE (See Figure 11.)
The trimmer is equipped with a line trimming cut-off blade on the guard. Replace the string when
trimming efciency diminishes. This will maintain best performance.
CUTTINg TIPS (See Figure 12.)
• Keep the trimmer tilted toward the area being cut; this is the best cutting area.
• The trimmer cuts when passing the unit from right to left. This will avoid throwing debris at the
operator. Avoid cutting in the dangerous area shown in gure 12.
• Use the tip of string to do the cutting; do not force string head into uncut grass.
• Wire and picket fences cause extra string wear and breakage. Stone and brick walls, curbs,
and wood may wear string rapidly.
• Avoid trees and shrubs. Tree bark, wood moldings, siding, and fence posts can easily be
damaged by the string.
DANgEROUS CUTTINg AREA
DIRECTION OF ROTATION
BEST CUTTINg AREA
Fig. 12
CUT-OFF BLADE
18
WARNINg
When servicing, use only identical replacement parts. Use of any other parts may create a hazard
or cause product damage.
WARNINg
Before inspecting, cleaning, or servicing the machine, shut off motor, wait for all moving parts
to stop, and disconnect extension cord. failure to follow these instructions can result in serious
personal injury or property damage.
gENERAL mAINTENANCE
Avoid using solvents when cleaning plastic parts. Most plastics are susceptible to damage from
various types of commercial solvents and may be damaged by their use. Use clean cloths to
remove dirt, dust, lubricant, grease, etc.
WARNINg
Do not at any time let brake uids, gasoline, petroleum-based products, penetrating lubricants, etc.,
come in contact with plastic parts. Chemicals can damage, weaken or destroy plastic which may
result in serious personal injury.
You can often make adjustments and repairs described here. For other repairs, have the power
head serviced by an authorized service dealer.
CLEANINg THE POWER HEAD
• Stop the motor and remove the battery.
• Clean dirt and debris from the power head using a damp cloth with a mild detergent.
Note: Do not use any strong detergents on the plastic housing or the handle. They can be damaged by certain
aromatic oils such as pine and lemon, and by solvents such as kerosene.
STORINg THE POWER HEAD
• Clean all foreign material from the product.
• Store it in a well-ventilated place that is inaccessible to children.
• Keep away from corrosive agents such as garden chemicals and de-icing salts.
WARNINg
Do not store the string trimmer in sunlight, in an excessively warm place, or near a furnace. The
battery life will be shortened.
MAINTENANCE
19
TROUBLESHOOTING
PROBLEm CAUSE SOLUTION
Motor fails to start when switch
trigger is depressed.
Check the battery charge. Recharge the battery per the
instructions in the battery
manual.
Check the power button. Push the power button if no
LED's are illuminated.
Battery is not secure. To secure the battery, make
sure the latches on the battery
compartment snap into place.
String trimmer stops while
cutting.
The trimmer head is bound
with grass.
Stop the trimmer, remove the
battery, and remove the grass
from the trimmer head.
The battery pack is too hot. Remove the battery and allow
it to cool in a cool; dry area.
The battery pack is fully
discharged.
Recharge the battery per the
instructions in the battery
manual.
Line will not advance. There is not enough line in the
spool.
Remove the battery and
replace the trimmer line.
20
LIMITED f OUR-YEAR WARRANTY
GREENWORKS™ hereby warranties this product, to the original purchaser with proof of
purchase, 4 year consumer warranty, 1 year commercial warranty against defects in materials,
parts or workmanship. GREENWORKS™, at its own discretion will repair or replace any and all
parts found to be defective, through normal use, free of charge to the customer. This warranty is
valid only for units which have been used for personal use that have not been hired or rented for
industrial/commercial use, and that have been maintained in accordance with the instructions in
the owners’ manual supplied with the product from new.
ITEmS NOT COVERED BY WARRANTY:
1. Any part that has become inoperative due to misuse, abuse, neglect, accident, improper
maintenance, or alteration; or
2. The unit, if it has not been operated and/or maintained in accordance with the owner's
manual; or
3. Normal wear, except as noted below;
4. Routine maintenance items such as lubricants, blade sharpening;
5. Normal deterioration of the exterior nish due to use or exposure.
gREENWORKS HELPLINE (1-855-345-3934):
Warranty service is available by calling our toll-free helpline, 9 a.m. to 5 p.m. EST. Monday-
friday at (1-855-345-3934).
TRANSPORTATION CHARgES:
Transportation charges for the movement of any power equipment unit or attachment are the
responsibility of the purchaser. It is the purchaser’s responsibility to pay transportation charges
for any part submitted for replacement under this warranty unless such return is requested in
writing by gREENWORKS.
21
EXPLODED VIEW
22
PARTS LIST
Item No. Part No. Description QTY
1 31109719 Power head assembly 1
2 31111719 Auxiliary handle 1
3 34101185-4 Auxiliary handle base 1
4 33303719 Auxiliary handle screw 4
5 31110719 Lower shaft assembly 1
6 31105719 Guard assembly 1
7 34108178A Dual line spool assembly 1
8 3220905B Battery 1
9 31105719 Washer 1
10 34108178A Spacer 1
11 3220905B Charger 1
TOLL-FREE HELPLINE: 1-855-345-3934
Rev: 00 (11-08-14) Printed in China on 100% Recycled Paper
