Oregon Professional Series User guide

Oregon® 120V Professional Series™
ST120VX-NA
String Trimmer / Coupe-bordure /
Recortadora
Original Instruction Manual
Manuel d’instruction original
Manual de instrucciones original

Instruction Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–22
Manuel d'instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-42
Manual de instrucciones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44-62

4String Trimmer Model ST120VX-NA
Table of Contents
Table of Contents
Important Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Safety Signal Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
General Power Tool Safety Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Safety Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
At a Glance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Unpacking and Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Unpacking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Intended Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Before Starting Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Batteries and Battery Charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Fitting the Backpack Battery Carrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Fit the Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Balance the String Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Starting the String Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Stopping the String Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Stealth Mode™. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Cutting Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Tool Reactivation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Dashboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Mounting the Trimmer Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Replacing Trimmer Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lubricating the Gearbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Tightening the Line Cutter Knife Screw . . . . . . . . . . . . . . . . . . . . . . . . . .18
Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
California Emission Control Air Index Information . . . . . . . . . . . . . . . . . . . . . . . .20
Commercial Warranty and Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Limited Warranty Coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Servicing Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Contact Us. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
California Emission Control Warranty Statement . . . . . . . . . . . . . . . . . . . . . . . .22
©  Blount, Inc. Pricing and specifications subject to change without notice. All rights reserved. Oregon® is a registered trademark of Blount, Inc.
in the United States and/or in other countries.

5
String Trimmer Model ST120VX-NA
Important Safety Information
Important Safety Information
WARNING: To reduce the risk of injury, read and understand this instruction manual before
using this product.
Save this manual for future reference.
Safety Signal Definitions
SYMBOL SIGNAL MEANING
DANGER Indicates that if the danger is not avoided, it will cause serious
property damage, injury or death.
WARNING Indicates that if the warning is not heeded, it can cause property
damage, serious injury or death.
CAUTION Indicates that if precautions are not taken, it may cause minor or
moderate injury, or property damage.
IMPORTANT Following this instruction will increase satisfaction with the tool.
General Power Tool Safety Warnings
WARNING: Read all safety warnings
and instructions. Failure to follow the
warnings and instructions may result in
electric shock, fire and/or serious injury.
Save all warnings and instructions for
future reference.
The term "power tool" in the warnings refers
to your mains-operated (corded) power tool or
battery operated (cordless) power tool.
WORK AREA SAFETY
• Keep work area clean and well lit.
Cluttered or dark areas invite accidents.
• Do not operate power tools in explosive
atmospheres, such as in the presence of
flammable liquids, gases or dust. Power
tools create sparks which may ignite the
dust or fumes.
• Keep children and bystanders away
while operating a power tool. Distractions
can cause you to lose control.
ELECTRICAL SAFETY
• Power tool plugs must match the outlet.
Never modify the plug in any way.
Unmodified plugs and matching outlets will
reduce the risk of electric shock.
• Avoid body contact with earthed or
grounded surfaces, such as pipes,
radiators, ranges and refrigerators.
There is an increased risk of electric shock if
your body is earthed or grounded.
• Do not expose power tools to rain or wet
conditions. Water entering a power tool
will increase the risk of electric shock. **
• Do not abuse the cord. Never use the
cord for carrying, pulling, or unplugging
the power tool. Keep cord away from
heat, oil, sharp edges or moving parts.
Damaged or entangled cords increase the
risk of electric shock.
• When operating a power tool outdoors,
use an extension cord suitable for
outdoor use. Use of a cord suitable for
outdoor use reduces the risk of electric
shock.

6String Trimmer Model ST120VX-NA
Important Safety Information
• If operating a power tool in a damp
location is unavoidable, use a ground
fault circuit interrupter (GFCI) protected
supply. Use of a GFCI reduces the risk of
electric shock. *
** Item above: “Do not expose power tools
to rain or wet conditions.” is applicable to
power tools in general; however, Oregon
battery operated V Professional Series
tools have been specifically designed for
operation during exposure to rain or wet
conditions.
* Item above: “If operating a power tool in a
damp location is unavoidable, use a ground
fault circuit interrupter (GFCI) protected supply.”
is applicable to corded power tools in general;
however, use of a GFCI with Oregon battery
operated V Professional Series tools is
not applicable.
PERSONAL SAFETY
• Stay alert, watch what you are
doing and use common sense when
operating a power tool. Do not use
a power tool while you are tired or
under the influence of drugs, alcohol or
medication. A moment of inattention while
operating power tools may result in serious
personal injury.
• Use personal protective equipment.
Always wear eye protection. Protective
equipment such as dust mask, non-skid
safety shoes, hard hat or hearing protection
used for appropriate conditions will reduce
personal injuries.
• Prevent unintentional starting. Ensure
the switch is in the off-position before
connecting to power source and/or
battery pack, picking up or carrying the
tool. Carrying power tools with your finger
on the switch or energizing power tools that
have the switch on invites accidents.
• Remove any adjusting key or wrench
before turning the power tool on. A
wrench or a key left attached to a rotating
part of the power tool may result in
personal injury.
• Do not overreach. Keep proper footing
and balance at all times. This enables
better control of the power tool in
unexpected situations.
• Dress properly. Do not wear loose
clothing or jewelry. Keep your hair,
clothing and gloves away from moving
parts. Loose clothes, jewelry or long hair
can be caught in moving parts.
• If devices are provided for the
connection of dust extraction and
collection facilities, ensure these are
connected and properly used. Use of dust
collection can reduce dust-related hazards.
• Do not let familiarity gained from
frequent use of tools allow you to
become complacent and ignore tool
safety principles. A careless action can
cause severe injury within a fraction of a
second.
POWER TOOL USE AND CARE
• Do not force the power tool. Use the
correct power tool for your application.
The correct power tool will do the job better
and safer at the rate for which it was designed.
• Do not use the power tool if the trigger
does not turn it on and off. Any power tool
that cannot be controlled with the trigger is
dangerous and must be repaired.
• Disconnect the plug from the power
source and/or remove the battery pack,
if detachable, from the power tool before
making any adjustments, changing
accessories, or storing power tools Such
preventive safety measures reduce the risk of
starting the power tool accidentally.
• Store idle power tools out of the reach
of children and do not allow persons
unfamiliar with the power tool or these
instructions to operate the power tool.
Power tools are dangerous in the hands of
untrained users.
• Maintain power tools. Check for
misalignment or binding of moving
parts, breakage of parts, and any other
condition that may affect the power tool’s
operation. If damaged, have the power
tool repaired before use. Many accidents
are caused by poorly maintained power tools.
• Keep cutting tools sharp and clean.

7
String Trimmer Model ST120VX-NA
Important Safety Information
7
Properly maintained cutting tools with sharp
cutting edges are less likely to bind and are
easier to control.
• Use the power tool, accessories and
tool bits etc. in accordance with these
instructions, taking into account the
working conditions and the work to
be performed. Use of the power tool for
operations different from those intended
could result in a hazardous situation.
• Keep handles and grasping surfaces
dry, clean and free from oil and grease.
Slippery handles and grasping surfaces do
not allow for safe handling and control of the
tool in unexpected situations.
BATTERY TOOL USE AND CARE
• Recharge only with the charger specified
by the manufacturer. A charger that is
suitable for one type of battery pack may
create a risk of fire when used with another
battery pack.
• Use power tools only with specifically
designated battery packs. Use of any
other battery packs may create a risk of
injury and fire.
• When battery pack is not in use, keep
it away from other metal objects, like
paper clips, coins, keys, nails, screws
or other small metal objects that can
make a connection from one terminal
to another. Shorting the battery terminals
together may cause burns or a fire.
• Under abusive conditions, liquid may be
ejected from the battery; avoid contact.
If contact accidentally occurs, flush
with water. If liquid contacts eyes, seek
medical help. Liquid ejected from the
battery may cause irritation or burns.
• Do not use a pack or tool that is damaged
or modified. Damaged or modified batteries
may exhibit unpredictable behavior resulting
in fire, explosion or risk of injury.
• Do not expose a battery pack or tool to
fire or excessive temperature. Exposure
to fire or temperature above  °C (
°F) may cause explosion.
• Follow all charging instructions and
do not charge the battery pack or tool
outside the temperature range specified
in the instructions. Charging improperly
or at temperatures outside the specified
range may damage the battery and increase
the risk of fire.
SERVICE
• Have your power tool serviced by a
qualified repair person using only
identical replacement parts. This will
ensure that the safety of the power tool is
maintained.
• Never service damaged battery packs.
Service of battery packs should only
be performed by the manufacturer or
authorized service providers.
STRING TRIMMER SAFETY WARNINGS
DANGER: Keep hands away from
trimming line. Contact with trimming line will
result in serious personal injury.
WARNING: To reduce risk of injury,
keep all parts of the body away from
the trimming line. Do not remove cut
material or hold material to be cut when
trimming line is moving. Make sure the
transportation lockout is activated when
clearing jammed material. Trimming line
coasts after being turned off. A moment of
inattention while operating the trimmer may
result in serious personal injury.
• Do not use any accessories other than
specific Trimmer Head and Trimmer Line
specified. The use of any other accessory or
attachment may increase the risk of injury.
• Keep guards in place and in working order.
• Oregon Professional Series V tools
have been specifically designed for safe
operation during exposure to rain or in
wet conditions, but should be stored in a
dry location.

8String Trimmer Model ST120VX-NA
Important Safety Information
Safety Symbols
These symbols appear on the STVX-NA.
SYMBOL MEANING EXPLANATION
Safety alert A danger, warning, or caution.
Follow instructions
Read and follow instructions in this manual
carefully before assembling, operating, or
servicing the product.
Protect bystanders
Clear the area of bystanders, children, and pets
within a minimum 50 ft (15 m) radius.
Encourage bystanders to wear eye protection.
Beware of flying debris
This product may throw debris, which can cause
personal injury or property damage, either
directly or by ricocheting 50 ft (15 m) or farther.
Make sure the guard and handle are correctly
installed and undamaged.
Use nylon cutting lines
only—never use metal
blades
Use only the nylon cutting lines recommended in
the Specifications section. Do not use wire, which
could break off and cause fatal injury.
Risk of eye injury
Protect your eyes and face
Wear protective safety glasses or goggles, a
face mask, and if necessary, an approved safety
hardhat. Guard against dust and debris-related
injuries and illnesses by controlling dust at the
source if possible.
Protect your body
Wear the appropriate, approved personal
protective equipment, including hearing
protection and substantial footwear.
Protect your hands
Wear heavy-duty, non-slip work gloves to
improve your grip and help protect your hands
when operating the tool.

9
String Trimmer Model ST120VX-NA
At a Glance
At a Glance
120v
1
3
2
4
4.1
4.2
4.5
4.6
4.7
4.3
4.4
4.4
10
11.1
11.2
11
12.1
12.6 12.7
12
12.2
12.4
12.3
13
5
6
7
7.1
5.1
8
9
2.2
2.1

10 String Trimmer Model ST120VX-NA
At a Glance
 Powerhead
 Powerhead Clamp
. Locking Screw/Washer
. Clamp Screws/Washers
 Power Socket
 Control Handle
. Transportation Lockout
. Trigger-Lock Lever
. Variable Speed Trigger
. Clamp Screws
. Dashboard
. Stealth Mode Indicator
. Stealth Mode Button
 Harness Loop
. Loop Screw
 Spacer Sleeve
 Front Handle
. Handle Screws/Washers
 Drive Tube
 Internal Drive Shaft
 Guard
 Line Cutter
. Knife
. Knife Screw
 String Trimmer Attachment
. Gearbox
. Threaded Shaft
. Thrust Plate
. Filler Zerk
. Shaft Block Hole
. Locking Screw/Washer
. Clamp Screw/Washer
 Trimmer Head
 Combination Tool
 Blocking Pin/Rubber Stopper
(stored inside of Combination Tool)
12.5
12.6
12.7
15
14

11
String Trimmer Model ST120VX-NA
Unpacking and Assembly
Unpacking and Assembly
Unpacking
What’s in the boxes?
The string trimmer requires assembly before
use. These items ship with the string trimmer:
• Powerhead
• Front trimmer handle
• Drive tube assembly
• Harness loop
• String trimmer attachment assembly
• Combination tool with blocking pin
Remove the string trimmer assemblies from
each box and inspect them carefully to ensure
no damage has occurred during shipping and
that no parts are missing. If any parts are
damaged or missing, do not use the string
trimmer. Contact Oregon®Customer Service to
obtain replacement parts at ...
Assembly
Place tool assemblies on a workbench.
. Loosen the harness loop screw () and
slide onto the motor housing end of the
drive tube. Wait until fully assembled to
tighten the screw.
. Remove the powerhead locking screw/
washer on the bottom of the powerhead ().
. Loosen the recessed control handle clamp
screws () and the powerhead clamp
screws (). Insert the motor housing end of
the drive tube through the control handle
and into powerhead clamp until it is firmly
seated in the powerhead ().
. Rotate the drive tube to locate and align to
the hole in the powerhead. Insert the
powerhead locking screw/washer () and
tighten to  inch-pounds with the included
combination tool..
WARNING: To reduce risk of injury, the
locking screw must be in place and tightened
properly.
. Tighten the powerhead clamp screws
to  inch-pounds with the included
combination tool.
. Position the control handle so that the
throttle cable is taut (). Align the control
handle to center the battery indicator over
the drive tube and tighten the recessed
clamp screws to  inch-pounds.
1
2
4
3
5
2
6

12 String Trimmer Model ST120VX-NA
Unpacking and Assembly
. Slide the harness loop to the control handle
() and tighten the clamp screw to  inch-
pounds.
. Slide the spacer sleeve to the harness
loop ().
. Loosen the screws on the front handle and
slide it onto the drive tube ().
. Push and rotate the internal drive shaft until
it seats into the powerhead ().
. Remove the attachment locking screw/
washer on top of the string trimmer
attachment ().
. Loosen the clamp screw on the string
trimmer attachment. Push and rotate the
string trimmer attachment until it couples
with the drive shaft ().
. Rotate to locate and align to the hole in the
drive tube. Insert the attachment locking
screw/washer and tighten to  inch-
pounds.
WARNING: To reduce risk of injury, the
locking screw must be in place and tightened
properly.
. Tighten attachment clamp screw to 
inch-pounds ().
. Align and adjust the front handle for a
comfortable working position and tighten
the clamp screw to  inch-pounds ().
Reposition as needed.
WARNING: To reduce risk of injury, all
guards must be in place.
7
8
9
10
11
12
13
14

13
String Trimmer Model ST120VX-NA
Operation
Operation
Intended Use
Use your string trimmer equipped with the
appropriate cutting attachment only for cutting
grass, light brush, and similar material. Do not
use it for other purposes, since misuse may
result in personal injury or property damage,
including damage to the machine.
Before Starting Work
Read the Original Instruction
Manual for the Battery and
Backpack Battery Carrier carefully
before assembling, operating, or
servicing the product.
• Check the battery, tool, and backpack battery
carrier are in good condition.
• Check for misalignment or bending of moving
parts, breakage of parts, and any other
condition that may affect the power tool’s
operation.
• Check that all guarding is in place and in good
condition.
• Check condition of backpack harnesses,
straps, and zippers.
• Make sure the battery cable, plug, and power
socket are not damaged.
To repair or replace any damage or worn
part, contact Oregon or an authorized Oregon
servicing dealer.
Batteries and Battery Charging
• Batteries must be used, stored and charged
within battery use, storage, charging
temperature ranges outlined in the
Specifications section of this manual.
• Oregon V Professional Series tools are
intended for use only with Oregon V
Professional Batteries. Read and follow all
instructions provided in the Oregon V
Professional Battery Operators Manual.
• Oregon V Professional Batteries must be
charged only by Oregon V Professional
Charger. Read and follow all instructions
provided in the Oregon V Professional
Charger Operators Manual.
Fitting the Backpack
Battery Carrier
WARNING: The Oregon V
Professional Batteries should only be used with
a battery carrier supplied by Oregon. Failure to
use any other carrier or method may result in
injury.
• Insert the Oregon Professional Series Battery
into the Backpack Battery Carrier.
• Insert the plug of the battery cable into the
battery socket—make certain the battery
plug is completely seated into the power
socket of the battery.
• Lift the backpack on your body and fit the
carrier as described in the Oregon Backpack
Battery Carrier Instructions Guide.
Fit the Harness
• Put on shoulder strap.
• Adjust length of strap. The carabiner ()
should be about a hand’s width below
operator’s hip.
• Detach harness by pressing down on the
carabiner bar and pull the harness loop ()
out of the carabiner.
Balance the String Trimmer
• Attach carabiner to the harness loop on the
drive tube.
• Loosen the screw ().
• Adjust harness loop.
• Tighten screw.
1
2

14 String Trimmer Model ST120VX-NA
Operation
• Check position and comfort by allowing
trimmer to hang freely.
• Make adjustments as necessary.
Starting the String Trimmer
• Before plugging in the string trimmer
make certain the transportation lockout is
activated.
• Fully insert the plug into the power socket.
When fully inserted, the LED lights on the
dashboard will activate and be accompanied
by an audible beep.
• Hold the power tool by both hands, with one
hand on the control handle and one hand on
the front handle.
• Deactivate the transportation lockout.
• Engage the trigger-lock lever and press the
variable speed trigger to activate the blade.
Continue to press the variable speed trigger
for normal operation.
Stopping the String Trimmer
• Release the variable speed trigger to stop the
trimmer head from spinning.
• Upon release of the variable speed trigger,
remove your hand from the trigger-lock lever.
Stealth Mode™
The Oregon STVX-NA has a Stealth
Mode which reduces peak speed by . The
STVX-NA in Stealth Mode can reduce noise
up to  and extend run time more than .
• To activate Stealth Mode, press the Stealth
Mode button beneath the dashboard. A blue
light above the button indicates the tool is in
Stealth Mode.
• Press the button again to deactivate Stealth
Mode and return to full speed.
Cutting Techniques
MOWING
Hold trimmer with both hands. Swing the
trimmer back and forth in an arc with the
cutting attachment at the desired cutting height.
Avoid contact with fences, walls, rocks,
sensitive plants and trees, etc.
Tool Reactivation
When the string trimmer has not been in use
for  seconds it will enter a dormant mode,
during which engaging the trigger lock lever
and pressing the variable speed trigger will
result in the blue Stealth Mode light blinking
rapidly.
• Press the Stealth Mode button and the string
trimmer will immediately re-activate and the
dashboard will show battery charge state.
3
120v

15
String Trimmer Model ST120VX-NA
Operation
Dashboard
The dashboard is located on the control handle of the Oregon STVX-NA and displays the current
charge state of the battery connected to the tool and any faults from the tool or battery.
INDICATORS
LEDs
5 green LEDs 4 green LEDs 3 green LEDs 2 green LEDs 1 green LED 1 red LED
MEANING Full charge
100% to 81% 80% to 61% 60% to 41% 40% to 21% 20% to 10% Low power <10%
To determine the approximate number of hours the tool has been operated, insert the battery plug
and press the Stealth Mode button for  seconds.
INDICATORS
LEDs
none blue LED flash
SOUND
1 beep beep
MEANING <49 hours 1 blue LED flash and beep
for every 50 hours

16 String Trimmer Model ST120VX-NA
Maintenance
Maintenance
Mounting the Trimmer Head
WARNING: To reduce risk of injury,
disconnect the battery from the power tool
before making any adjustments, changing
accessories, or transporting.
• Use only Oregon Lightning Load trimmer
head.
• Place the string trimmer so that the threaded
shaft () coming out of the gear box faces
upwards.
• Be sure that the thrust plate () is in place on
the gear box over the spline on the threaded
shaft.
• Insert the blocking pin into the shaft block
hole () in the gear box so that the pin stops
the threaded shaft rotation. Note, the shaft
block hole has a rubber stopper designed to
hold the blocking pin in place while mounting
or removing the trimmer head.
• With the blocking pin in place and one hand
holding the gear box, rotate the trimmer head
counter clockwise with other hand to tighten
FIRMLY until you can no longer rotate the
head ().
• Remove the blocking pin from the gear box.
• Remove the trimmer head in reverse, rotating
the trimmer head clockwise ().
Replacing Trimmer Line
WARNING: To reduce risk of injury,
disconnect the battery from the power tool
before making any adjustments, changing
accessories, or transporting.
Before replacing the trimmer line:
• Use only Oregon ." Magnum Supertwist
Line or Generic . mm round nylon line.
• Pull any remaining trimmer line through an
eyelet of the trimmer head.
• Cut a length of new trimmer line about  ft
(. m) long.
• Turn the knob so the arrows on the surface of
the head point to the eyelets on the trimmer
head.
To replace the trimmer line:
• Insert trimmer line through an eyelet in the
side of the trimmer head () until the trailing
end of the trimmer line exits through the
other eyelet in the trimmer head ().
1
2
3
4 5
2
1

17
String Trimmer Model ST120VX-NA
Maintenance
• Pull the leading end of the trimmer line until
the leading end and the trailing end are about
the same length ().
• Turn the knob counter-clockwise () to wind
the trimmer line.
• Pull both ends of the trimmer line to tighten
the line inside the trimmer head ().
• Turn the knob counter-clockwise to wind the
line until about – in (– cm) of line
protrudes from each eyelet ().
Lubricating the Gearbox
WARNING: To reduce risk of injury,
disconnect the battery from the power tool
before making any adjustments, changing
accessories, or transporting.
CAUTION: To reduce risk of injury,
check the grease level after every 
hours of operation and add Premium High
Temperature Lithium Wheel Bearing
Grease Grade NLGI  as follows:
• Unscrew filler zerk.
• Assess grease level on the inside of gearbox.
• Refit and firmly tighten the filler zerk.
• If no grease was visible, use a grease gun
fitted with a needle tip adapter (see below) to
insert no more than  g (. oz.) of grease into
the gearbox.
3
4
5
6

18 String Trimmer Model ST120VX-NA
Maintenance
Tightening the Line
Cutter Knife Screw
WARNING: To reduce risk of injury,
disconnect the battery from the power tool
before making any adjustments, changing
accessories, or transporting.
Periodically check the line cutter knife screw to
maintain cutter connection. Firmly tighten as
needed.

19
String Trimmer Model ST120VX-NA
Troubleshooting
Troubleshooting
All of the tools in the Oregon Professional Series have the ability to self-diagnose issues.
Below is a table of fault codes the tool can display through the dashboard.
INDICATORS POSSIBLE
CAUSE
RECOMMENDED
ACTION
LEDs SOUND
none none Trigger not pulled. Pull trigger.
No power. Make certain the plug
is fully seated in socket.
1 continuous red light
red
steady on Cutting head is
jammed.
Disconnect the battery
plug from tool and
remove obstruction
from cutting head.
1 slow blinking red light
red
slow beep
(repeating) Battery is fully
discharged. Charge battery.
alternating green and red lights
green red
rapid beep
(repeating) Battery fault.
Try a different battery.
Contact authorized
repair center.
4 green, 1 red, 1 blue quick blinking lights
green green green green red blue
very rapid
short beep
(repeating) Hardware fault.
Unplug, wait 30
seconds, plug back in.
Service tool.
Contact authorized
repair center.
1 short, 1 long blinking red light
red
1 short,
1 long beep Battery too hot. Try a different battery.
Allow battery to cool.
2 short, 1 long blinking red light
red
2 short,
1 long beep Tool over temp.
Allow tool to cool.
Check for blocked
vents.
4 green and 1 red continuous lights
green green green green red
none
Failed dashboard. Replace dashboard.
5 blinking green lights
green green green green green
none Trigger pulled
while battery plug
inserted.
Release trigger.
Unplug tool.
Check for stuck trigger.
Plug in tool.

20 String Trimmer Model ST120VX-NA
Specifications
Specifications
For a full list of replacement parts, please visit OregonProducts.com.
TRIMMER ST120VX-NA
Weight (w/ trimmer head) 12.1 lb (5.5 kg)
Length (w/ trimmer head) 73.5 in (1867 mm)
Swath diameter 16.5 in (420 mm)
Replacement line Use only Oregon 0.095" Magnum Supertwist Line or Generic 0.095 mm
round nylon line.
Replacement head Use only Oregon Lighting Load trimmer head.
HIGH STEALTH MODE
Trimmer head speed 5500 rpm 4400 rpm
Bystander decibel rating
(per ANSI B172.3) 62 dB(A) 52 dB(A)
Run time estimates
(with BX975 Battery) 2.6 hours 4.1 hours
TEMPERATURE RANGES
Operating temperature range 14°F to 113°F (-10°C to 45°C)
Charging temperature range 32°F to 86°F (0°C to 30°C)
Storage temperature range -4°F to 140°F (-20°C to 60°C)
California Emission Control Air Index Information
California Emission Control Air Index Information
The Air Index of this engine is 0
0 2 4 6 8 10
Most Clean Least Clean
Note: The lower the Air Index, the less pollution.
This engine is certified to be emissions
compliant for the following use: 300 hours
Emissions Durability Period
The stated Durability Period listed on Oregon 120V Professional Series equipment refers
only to the minimum emissions period tools must meet or exceed to qualify as Zero
Emission Equipment in the State of California.