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© 10/24 ECHO Incorporated
Operator’s
Manual
SRM-2120
Grass Trimmer /
Brushcutter
The engine exhaust from this product contains chemicals
known to the State of California to cause cancer, birth defects,
or other reproductive harm.
Read and understand all provided literature before
use. Failure to do so could result in serious injury.
Note: This product complies with CAN ICES-2/NMB-2.
TABLE OF CONTENTS SRM-2120
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TABLE OF CONTENTS
Introduction................................................................................................................. 3
Servicing Information.................................................................................................. 4
Parts and Serial Number.................................................................................... 4
Service ............................................................................................................... 4
ECHO Consumer Product Support .................................................................... 4
Product Registration........................................................................................... 4
Additional Literature ........................................................................................... 4
Safety ......................................................................................................................... 5
Manual Safety Symbols and Important Information ........................................... 5
International Symbols......................................................................................... 6
Personal Condition and Safety Equipment ........................................................ 8
Equipment ........................................................................................................ 13
Emission Control . (Exhaust & Ev
aporative) ............................................................ 15
EPA Emissions Control Information ................................................................. 15
Description ............................................................................................................... 16
Contents................................................................................................................... 17
Assembly.................................................................................................................. 18
Support Handle Installation .............................................................................. 18
Operation.................................................................................................................. 18
Operation with Blades ...................................................................................... 19
Blade Selection ................................................................................................ 21
Fuel .................................................................................................................. 22
Starting Cold Engine ........................................................................................ 25
Starting Warm Engine ...................................................................................... 27
Stopping Engine............................................................................................... 28
Applications...................................................................................................... 28
Operating Techniques - Nylon Line Head ........................................................ 29
Operating Techniques - Metal or Plastic Blade ................................................ 30
Reaction Forces ............................................................................................... 30
Blade Cutting Problems ................................................................................... 32
Maintenance............................................................................................................. 33
Skill Levels ....................................................................................................... 33
Maintenance Intervals ...................................................................................... 34
Air Filter............................................................................................................ 35
Fuel Filter ......................................................................................................... 36
Spark Plug........................................................................................................ 37
Cooling System ................................................................................................ 37
Exhaust System ............................................................................................... 39
Carburetor Adjustment ..................................................................................... 40
Lubrication........................................................................................................ 42
Sharpening Metal Blades ................................................................................. 43
Troubleshooting........................................................................................................ 44
Storage..................................................................................................................... 46
Long-Term Storage (Over 30 Days) ................................................................. 46
Specifications ........................................................................................................... 47
Product Registration................................................................................................. 48
SRM-2120 INTRODUCTION
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INTRODUCTION
Specifications, descriptions, and illustrative material in this literature are as
accurate as possible. Specifications are subject to change without notice.
Illustrations might include optional equipment and accessories, and might
not include all standard equipment. Your equipment might appear slightly
different than pictured equipment.
Read and understand all provided literature.
Literature contains specifications and
information for safety, operation,
maintenance, storage, and assembly specific
to this product. Scan QR codes for more
information.
For additional literature, including safety manuals where applicable, or
questions regarding terms used in this manual, visit:
https://www.echo-usa.com/manuals
OR
https://www.shindaiwa-usa.com/manuals
SERVICING INFORMATION SRM-2120
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SERVICING INFORMATION
Parts and Serial Number
Genuine ECHO parts and
assemblies for your ECHO products
are available only from an
Authorized ECHO Dealer. When
you do need to buy parts, always
have the model number and serial
number of the unit with you. For
future reference write them in the
space provided below.
Model No. _____________________ Serial No. _____________________
Service
Service of this product during the warranty period must be performed by an
Authorized ECHO Service Dealer. For the name and address of the
Authorized ECHO Service Dealer nearest you, ask your retailer or call:
1-800-432-ECHO (3246). Dealer information is also available on our Web
Site www.echo-usa.com. When presenting your unit for Warranty service/
repairs, proof of purchase is required.
ECHO Consumer Product Support
If you require assistance or have questions concerning the application,
operation, or maintenance of this product, call the ECHO Consumer
Product Support Department at 1-800-432-ECHO (3246) from 8:00 a.m. to
5:00 p.m. (Central Standard Time) Monday through Friday. Before calling,
please know the model and serial number of your unit.
Product Registration
Register your ECHO equipment online at www.echo-usa.com or by filling
out the product registration sheet included in this manual. Registering your
product confirms warranty coverage and provides a direct link to ECHO if
we find it necessary to contact you.
Additional Literature
In addition to finding information online, information is available from your
Authorized ECHO Service Dealer, or by contacting ECHO Incorporated,
400 Oakwood Road, Lake Zurich, IL 60047, 1-800-432-ECHO (3246).
SRM-2120 SAFETY
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SAFETY
Manual Safety Symbols and Important Information
Throughout this manual and on the product itself, you will find safety alerts
and helpful, informational messages preceded by symbols or key words.
The following is an explanation of those symbols and key words and what
they mean to you.
The safety alert symbol accompanied by the word “DANGER”
calls attention to an act or condition which WILL lead to serious
personal injury or death if not avoided.
The safety alert symbol accompanied by the word “WARNING”
calls attention to an act or condition which CAN lead to serious
personal injury or death if not avoided.
The safety alert symbol accompanied by the word “CAUTION”
calls attention to an act or condition which might lead to minor
or moderate personal injury if not avoided.
The enclosed message provides information necessary for the
protection of the unit.
Note: This enclosed message provides tips for use, care and
maintenance of the unit.
CIRCLE AND SLASH SYMBOL
This symbol means the specific action shown is prohibited.
Ignoring these prohibitions can result in serious or fatal injury.
SAFETY SRM-2120
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International Symbols
Symbol Description Symbol Description
Warning, See
Operator’s
Manual
Carburetor
Adjustment - High
Speed Mixture
Wear Eye, Ear
and Head
Protection
Carburetor
Adjustment - Idle
Speed
Wear Hand and
Foot Protection
Carburetor
Adjustment - Low
Speed Mixture
Safety/Alert STOP Switch
Hot Surface
Fuel and Oil
Mixture
DO NOT Allow
Flames or
Sparks Near
Fuel
Ignition
ON / OFF
DO NOT Smoke
Near Fuel
Purge Bulb
Choke Control
RUN Position
(Choke Open)
Choke Control
COLD START
Position (Choke
Closed)
Keep Feet Away
From Blade
Rotating Cutting
Attachment
H
T
L
STOP
Ignition
OFF
ON
SRM-2120 SAFETY
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Note: Not all symbols will appear on your unit.
Thrown Objects Direction of Blade
DO NOT USE
LINE HEADS -
Blades Only
DO NOT USE
BLADES - Line
Heads Only
Keep Bystanders and Helpers
Away 15 m (50 ft.)
AVOID KICKOUT
Keep Bystanders At Least 15 m
(50 ft.) Away
Beware Thrown Objects Wear Eye
Protection
Symbol Description Symbol Description
SAFETY SRM-2120
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Personal Condition and Safety Equipment
Cancer and Reproductive Harm
www.P65Warnings.ca.gov
The muffler or catalytic muffler and surrounding cover
may become extremely hot. If unit is equipped with
muffler, always keep clear of exhaust and muffler area,
otherwise serious personal injury might occur.
Users of this product risk injury to themselves and others if the
unit is used improperly and/or safety precautions are not
followed. Proper clothing and safety gear must be worn when
operating unit.
Physical Condition
Your judgment and physical dexterity may not be good:
• If you are tired or sick
• If you are taking medication
• If you have taken alcohol or drugs
Operate unit only if you are physically and mentally well.
Eye Protection
Eye protection that meets ANSI Z87.1 or CE requirements
must be worn whenever you operate the unit.
For additional safety, a full-face shield can be worn over
safety glasses or goggles to provide protection from sharp
branches or flying debris.
SRM-2120 SAFETY
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Hand Protection
Wear sturdy, no-slip, rubber work gloves to improve your grip on the
handles. Gloves also provide protection against cuts and scratches, cold
environments, and reduce the transmission of machine vibration to your
hands.
Hearing and Ear Protection
ECHO recommends wearing personal protective equipment whenever unit
is used.
Breathing Protection
Operators who are sensitive to dust or other common airborne allergens
may need to wear a dust mask to prevent inhaling these materials while
operating unit. Dust masks can provide protection against dust, plant debris,
and other plant matter such as pollen. Make sure the mask does not impair
your vision, and replace the mask as needed to prevent air restrictions.
Proper Clothing
Wear snug-fitting, durable clothing:
• Pants should have long legs, shirts should have long sleeves.
• DO NOT WEAR SHORTS.
• DO NOT WEAR TIES, SCARVES, JEWELRY, or clothing with loose or
hanging items that could become entangled in moving parts or
surrounding growth.
• Keep clothing buttoned or zipped, and keep shirt tails tucked in.
• Wear sturdy work shoes with nonskid rubber soles.
• DO NOT WEAR OPEN TOED SHOES.
• DO NOT OPERATE UNIT WITH BARE FEET.
Keep long hair away from engine and air intake. Retain hair with cap or net.
Heavy protective clothing can increase operator fatigue, which may lead to
heat stroke. Schedule heavy work for early morning or late afternoon hours
when temperatures are cooler.
SAFETY SRM-2120
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The components of this machine generate an electromagnetic
field during operation, which can interfere with some
pacemakers. To reduce the risk of serious or fatal injury,
persons with pacemakers should consult with their physician
and the pacemaker manufacturer before operating this
machine. In the absence of such information, ECHO does not
recommend the use of this machine by anyone who has a
pacemaker.
Extended Operation and Extreme Conditions
Prolonged exposure to cold and/or vibration can result in injury.
Read and follow all safety and operation instructions to
minimize risk of injury. Failure to follow instructions can result
in painful wrist/hand/arm injuries.
It is believed that a condition called Raynaud’s Phenomenon, which affects
the fingers of certain individuals, may be brought about by exposure to
vibration and cold. Exposure to vibration and cold may cause tingling and
burning sensations, followed by loss of color and numbness in the fingers.
The following precautions are strongly recommended, because the
minimum exposure, which might trigger the ailment, is unknown.
• Keep your body warm, especially the head, neck, feet, ankles, hands, and
wrists.
• Maintain good blood circulation by performing vigorous arm exercises
during frequent work breaks, and also by not smoking.
• Limit the hours of operation. Try to fill each day with jobs where operating
the unit or other hand-held power equipment is not required.
• If you experience discomfort, redness, and swelling of the fingers
followed by whitening and loss of feeling, consult your physician before
further exposing yourself to cold and vibration.
SRM-2120 SAFETY
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Repetitive Stress Injuries (RSI)
It is believed that overusing the muscles and tendons of the fingers, hands,
arms, and shoulders may cause soreness, swelling, numbness, weakness,
and extreme pain in those areas. Certain repetitive hand activities may put
you at a high risk for developing a Repetitive Stress Injury (RSI). An
extreme RSI condition is Carpal Tunnel Syndrome (CTS), which could occur
when your wrist swells and squeezes a vital nerve that runs through the
area. Some believe that prolonged exposure to vibration may contribute to
CTS. CTS can cause severe pain for months or even years.
To reduce the risk of RSI/CTS, do
the following:
• Avoid using your wrist in a bent,
extended, or twisted position.
Instead try to maintain a straight
wrist position. Also, when
grasping, use your whole hand,
not just the thumb and index
finger.
• Take periodic breaks to minimize
repetition and rest your hands.
• Reduce the speed and force with
which you do the repetitive
movement.
• Do exercises to strengthen the
hand and arm muscles.
• Immediately stop using all power equipment and consult a doctor if you
feel tingling, numbness, or pain in the fingers, hands, wrists, or arms. The
sooner RSI/CTS is diagnosed, the more likely permanent nerve and
muscle damage can be prevented.
All overhead electrical conductors and communications wires
can have electricity flow with high voltages. This unit is not
insulated against electrical current. Never touch wires directly
or indirectly, otherwise serious injury or death can result.
Do not operate gas-powered products indoors or in
inadequately ventilated areas. Engine exhaust contains
poisonous emissions and can cause serious injury or death.
SAFETY SRM-2120
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Read Manuals
• Provide all users of this equipment with literature for instructions on safe
operation.
Clear the Work Area
• Always clear the work area of foreign objects such as rocks, broken
glass, nails, wire, or string, and check for any hidden hazards. Spectators
and fellow workers must be warned, and children and animals prevented
from coming nearer than 15 m (50 ft.) while the unit is in use.
• Outside the 15 m (50 ft.) zone, there is still a risk of injury from thrown
objects.
• Bystanders should be encouraged to wear eye protection.
• If you are approached, stop the engine and cutting attachment.
• When a bladed unit is used, there is the added risk of injury to bystanders
being struck with the moving blade in the event of a blade thrust or other
unexpected reaction of the blade.
Keep a Firm Grip
• Always hold throttle handle and support handle with thumbs and fingers
tightly encircling the handles.
Keep a Solid Stance
• Maintain footing and balance at all times. Do not stand on slippery,
uneven or unstable surfaces. Do not work in odd positions or on ladders.
Do not overreach.
• Keep cutting attachment below waist.
• Keep all body parts away from rotating cutting attachment.
Avoid Hot Surfaces
• If unit is equipped with muffler, keep exhaust area
clear of flammable debris. Avoid contact during and
immediately after operation.
SRM-2120 SAFETY
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Equipment
Use only approved attachments. Serious injury may result from
the use of a non-approved attachment combination. ECHO
Incorporated will not be responsible for the failure of cutting
devices, attachments or accessories which have not been
tested and approved by ECHO Incorporated. Read and comply
with all safety instructions.
Do not attempt to modify this product. Serious injury can
result from the use of any modified product.
Check unit for loose or missing nuts, bolts, and screws.
Tighten or replace as needed.
Inspect shield for damage and ensure that shield is
properly installed, and that the cut-off knife is securely in
place. Replace if either is damaged or missing.
Check that the cutting attachment is firmly attached and in
safe operating condition.
Manufacturer recommended flexible non-metallic line is
installed in the trimmer head.
Ensure that throttle trigger, throttle trigger lockout, and
stop switch all work properly.
Check that handle and harness (if included) are installed
and adjusted for safe, comfortable operation. See
Assembly Section for proper adjustment.
Moving parts can amputate fingers or cause severe injuries.
Keep hands, clothing and loose objects away from all openings.
ALWAYS stop engine, disconnect spark plug, and make
sure all moving parts have come to a complete stop before
assembling unit, removing obstructions, clearing debris,
or servicing unit.
Do not connect spark plug lead to spark plug until unit is
ready for use.
DO NOT start or operate unit unless all guards and
protective covers are properly assembled to unit.
NEVER reach into any opening while the engine is running.
Moving parts may not be visible through openings.
SAFETY SRM-2120
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Position wiring safely to prevent snagging, separation of
connectors, or breakage during operation. Gather excess
wire, and secure with wiring clamp if provided on
equipment, or tuck behind the air filter area. Do not place
wiring directly against hot engine components.
Check wiring and connectors for nicks, cuts, exposed wire,
or other damage, and repair or replace as needed. Exposed
wire or connectors can cause shocks, sparks, and risk of
fire or explosion, resulting in serious injury.
Check wire terminals for secure connections.
Periodically check fuel system (fuel lines, vent, grommet, fuel
tank, and fuel cap) for leaks especially if the unit is dropped. If
damage or leaks are found, do not use unit, otherwise serious
personal injury or property damage may occur. Have unit
repaired by an authorized servicing dealer before using.
SRM-2120
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EMISSION CONTROL (EXHAUST &
EVAPORATIVE)
EPA Emissions Control Information
The emission control system for
the engine is EM (engine
modification) and, if the second to
last character of the Engine Family
on the Emission Control
Information label (see example) is
“B”, “C”, “K”, or “T”, the emission
control system is EM and TWC
(3-way catalyst). The fuel tank/fuel
line emission control system is EVAP (evaporative emissions).
An Emission Control Label is located on the engine. (This is an
EXAMPLE ONLY, information on label varies by engine FAMILY).
Product Emission Durability (Emission Compliance Period)
The 50 or 300 hour emission compliance period is the time span selected by
the manufacturer certifying the engine emissions output meets applicable
emissions regulations, provided that approved maintenance procedures are
followed as listed in the Maintenance Section of this manual.
EMISSION CONTROL INFORMATION
ENGINE FAMILY: XEHXS.0214KO DISPLACEMENT: 21.2 cc
EMISSION COMPLIANCE PERIOD: 300 Hours
THIS ENGINE MEETS U.S.EPA EXH/EVP EMISSION
REGULATIONS FOR MODEL YEAR XXXX REFER TO OWNER'S MANUAL
FOR MAINTENANCE SPECIFICATIONS AND ADJUSTMENTS.
DESCRIPTION SRM-2120
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DESCRIPTION
Locate the safety decal(s) or etching(s) on your unit. Make sure they are
legible, and that you understand and follow the instructions. If any cannot be
read, replacements can be ordered from your ECHO dealer. Images shown
below are for example only. Those on your unit might appear slightly
different.
1
2
3
4
5
6
7
8
9
10
11
12
14
13
15
16
17
18
19
SRM-2120 CONTENTS
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CONTENTS
The ECHO product you purchased has been factory pre-assembled for your
convenience. Due to packaging restrictions, some assembly may be
necessary.
After opening the carton, check for damage. Immediately notify your retailer
or ECHO Dealer of damaged or missing parts. Use the contents list to check
for missing parts.
1. Spark plug
2. Top guard
3. Recoil starter handle
4. Spark arrester muffler or spark arrester muffler with catalyst
5. Fuel tank cap
6. Fuel tank
7. Air filter
8. Choke lever
9. Purge bulb
10. Power head
11. Throttle handle - for right hand
12. Throttle trigger lockout
13. Throttle trigger
14. Stop switch
15. Support handle - for left hand
16. Drive shaft assembly
17. Debris shield with cut-off knife
18. Cut-off knife
19. Rapid Loader® head
1 Power head / drive shaft assembly
1 Quick start guide
1 Warranty statement
ASSEMBLY SRM-2120
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ASSEMBLY
Support Handle Installation
Note: Label shows minimum
spacing for support
handle location.
1. If necessary, position support
handle for comfortable
operation and securely tighten
screws.
OPERATION
Moving parts can amputate fingers or cause severe injuries.
Keep hands, clothing and loose objects away from all openings.
Always stop engine, disconnect spark plug, and make sure all
moving parts have come to a complete stop before removing
obstructions, clearing debris, or servicing unit.
Engine exhaust IS HOT, and contains Carbon Monoxide (CO), a
poison gas. Breathing CO can cause unconsciousness, serious
injury, or death. Exhaust can cause serious burns. ALWAYS
position unit so that exhaust is directed away from your face
and body.
Operation of this equipment may create sparks that can start
fires around dry vegetation. This unit is equipped with a spark
arrester to prevent discharge of hot particles from the engine.
Metal cutters can also create sparks if the cutter strikes rocks,
metal, or other hard objects. Contact local fire authorities for
laws or regulations regarding fire prevention requirements.
SRM-2120 OPERATION
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Operation with Blades
Metal blades are very sharp and can cause severe injuries, even
if unit is off and blades are not moving. Avoid contact with
blades. Wear gloves to protect hands.
Blade use demands specific brushcutter configuration.
Operation without specified shield, barrier bar or U-handle, and
harness can result in serious personal injury. Follow installation
instructions.
Material to be cut Grass
Weed/
Grass
Weed/
Grass
Brush
<12.7 mm
(0.5 in.
)
Clearing
<63.5 mm
(2.5 in.)
Cutting Attachment
Nylon line
head
Maxi-Cut
head / Pro
Maxi-Cut
Head
3 tooth
blade /
8 tooth
blade
80 tooth
blade
22 tooth
blade
You must
install
these parts
Shield
Standard debris shield
included with SRM,
DSRM, T, PAS and DPAS
trimmer attachments, or
GT models (PRO Maxi-
Cut Head is not rated for
GT models)
Brushcutter shield supplied with U and
C model brushcutters, blade
conversion kit or PAS and DPAS
brushcutter attachments
Handle
Standard handle included
with SRM, DSRM, T, PAS
and DPAS or GT models
(PRO Maxi-Cut Head is
not rated for GT models)
U-Handle* or support handle with
barrier bar supplied with U and C model
brushcutters, blade conversion kit or
PAS and DPAS brushcutter
attachments
Harness
Not required**
Harness*** supplied with U and C
model brushcutters and blade
conversion kit
Upper/
lower plate
adapter
and
washer
Not
required
Washer
required,
included
with cutting
attachment
Upper/Lower blade plate adapter
included with U and C model
brushcutters, blade conversion kit or
PAS and DPAS brushcutter
attachments
OPERATION SRM-2120
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*ANSI standards require brushcutters be equipped with a support handle
with barrier bar or restrictive harness. U-Handle ensures a higher safety
factor.
** Grass trimmers do not require a harness if dry weight is below 6.0 kg
(13.2 lb). For grass trimmers having a dry weight of 6.0 kg (13.2 lb) to 7.5 kg
(16.5 lb), a single-shoulder harness is required. A harness may be used as
outlined in the Operator's Manual.
*** Brushcutters require at least a single shoulder harness if the dry weight
is below 7.5 kg (16.5 lb).
Do not install blades on GT (Curved Shaft) model trimmers.
• Use only ECHO approved parts. Failure to use the correct parts can
cause the blade to fly off. Serious injury to the operator and/or bystanders
can occur.
• Arbor diameter of upper blade plate must match arbor diameter of blades.
• For barrier bar or U-handle, follow instructions supplied with either blade
conversion kit or U-handle kit, and verify blade is secured properly.
• A new cotter pin is required each time a blade is installed.
• Shoulder harnesses may be used on all trimmers and brushcutters to
reduce operator fatigue. Brushcutters over 7.5 kg (16.5 lbs.) and U-
handle brushcutters require a double shoulder harness.
Note: The barrier bar is used to restrict rearward movement of the
unit. The barrier bar is not a handle and should not be
gripped when using or carrying the unit.
You must
install
these parts
Hex nut
Not
required
Hex nut
required,
included
with cutting
attachment
Hex nut required, included with U and C
model brushcutters, blade conversion
kit or PAS and DPAS brushcutter
attachments
Cotter pin
Not
required
New cotter
pin included
with cutting
attachment
New cotter pin included with U and C
model brushcutters, blade conversion
kit or PAS and DPAS brushcutter
attachments
Material to be cut Grass
Weed/
Grass
Weed/
Grass
Brush
<12.7 mm
(0.5 in.
)
Clearing
<63.5 mm
(2.5 in.)
SRM-2120 OPERATION
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Blade Selection
An improper or dull blade can cause serious personal injury.
The type of blade used must be matched to the type and size of
material cut. Blades must be sharp. Dull blades increase the
chance of kick-out and injury to yourself and bystanders. Never
use an edging blade, circular saw blade, or any other type of
unapproved blade.
Not all blades are compatible with all trimmers. Visit www.echo-
usa.com or www.shindaiwa-usa.com to find compatible blades.
3-Tooth Grass/Weed Blade may be used wherever the nylon line head is
used. DO NOT use this blade for heavy weeds or brush.
8-Tooth Weed/Grass Blade is designed for grass, garden debris and thick
weeds up to 19 mm (0.75 in.) diameter. DO NOT use this blade for brush or
heavy woody growth.
80-Tooth Brush Blade is designed for cutting brush and woody growth up
to 13 mm (0.5 in.) diameter.
22-Tooth Clearing Blade is designed for dense thickets and saplings up to
64 mm (2.5 in.) diameter.
A trimmer/brushcutter with a metal blade can cause serious
injuries if handled improperly.
Always use extreme care when
carrying or handling the equipment
to avoid contact with the cutting
edges of the blade. Use the optional
blade cover when unit is not in use.
Keep blades in protective packaging
until ready to install. Store blades
safely after removal to prevent injury
from accidental contact.
Use blade protectors to protect
blade teeth during unit
transportation.
OPERATION SRM-2120
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Use Shoulder/Waist Harness
Use of the shoulder/waist harness is
recommended for all trimmer/
brushcutter use, not just blade
operation. The shoulder/waist
harness when used in a trimming
operation with nylon line head
suspends the trimmer from the
operator's shoulder and reduces
operator fatigue.
During blade operation, the same
fatigue reduction is achieved. Safety
to the operator is also enhanced by
reducing the possibility of blade
contact with the operator's hands and feet by restricting trimmer movement.
Make sure the warning sign on the back of the shoulder harness can be
read easily.
Note: In case of emergency, disconnect the trimmer from the
harness.
Fuel
Diesel fuels and alternative fuels, such as E-15 (15% ethanol),
E-85 (85% ethanol) or any fuels not meeting ECHO requirements
are NOT approved for use in ECHO two-stroke gasoline engines.
Use of diesel or alternative fuels can cause performance
problems, loss of power, overheating, fuel vapor lock, and
unintended machine operation, including, but not limited to,
improper clutch engagement. Diesel or alternative fuels can
also cause premature deterioration of fuel lines, gaskets,
carburetors and other engine components.
Fuel Requirements
Gasoline - Use fresh (purchased within the last 30 days from the pump) 89
Octane [R+M/2] (mid grade or higher) gasoline known to be good quality.
Gasoline may contain up to 10% Ethanol (grain alcohol) or 15% MTBE
(methyl tertiary-butyl ether). Gasoline containing methanol (wood alcohol) is
NOT approved. Use of ECHO branded fuel is recommended to extend
engine life in all air-cooled two-stroke and two/four stroke hybrid engines.
SRM-2120 OPERATION
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Two-Stroke Oil - A two-stroke engine oil, such as ECHO branded two-
stroke oils, meeting ISO-L-EGD (ISO/CD 13738) and J.A.S.O. FD
Standards must be used. ECHO branded two-stroke oils meet these
standards. Engine problems due to inadequate lubrication caused by failure
to use an ISO-L-EGD (ISO/CD 13738) and J.A.S.O. M345-FD certified oil
will void the two-stroke engine warranty.
Two-stroke engine oil contains petroleum distillates and other
additives that may be harmful if swallowed. Heated oil can
release vapors that can cause flash fire, or ignite with explosive
force. Read and follow the oil manufacturer’s instructions, and
observe all safety warnings and precautions for handling
flammable liquids. For more detailed safety and first aid
information, visit www.echo-usa.com for a copy of the Material
Safety Data Sheet.
KEEP OUT OF REACH OF CHILDREN.
If swallowed, do not induce vomiting. CALL PHYSICIAN OR
A POISON CONTROL CENTER IMMEDIATELY.
WEAR SAFETY GLASSES when mixing or handling.
AVOID repeated or prolonged skin contact.
AVOID inhaling oil mists or vapors.
ECHO branded two-stroke oils may be mixed at 50:1 ratio for
application in all ECHO engines sold in the past regardless of ratio
specified in those manuals.
Handling Fuel
Fuel is flammable. Use extreme care when mixing, storing or
handling, or serious personal injury will result.
Use an approved fuel container. Mark fuel containers as
containing two-stroke mixture fuel.
DO NOT smoke near fuel.
DO NOT allow flames or sparks near fuel.
Fuel tanks/cans may be under pressure. Always loosen
fuel caps slowly allowing pressure to equalize.
NEVER refuel a unit when the engine is HOT or RUNNING!
OPERATION SRM-2120
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DO NOT fill fuel tanks indoors. ALWAYS fill fuel tanks
outdoors over bare ground.
DO NOT overfill fuel tank. Wipe up spills immediately.
Securely tighten fuel tank cap and close fuel container
after refueling.
Inspect for fuel leakage. If fuel leakage is found, do not
start or operate unit until leakage is repaired.
Use caution when handling fuel. Mix and pour fuel
outdoors where there are no sparks and flames. Slowly
remove the fuel cap only after stopping the engine and
allowing the unit to cool. Do not smoke while fueling or
mixing fuel. Move the unit at least 3 m (10 ft.) from the
fueling point before starting the engine.
Gasoline vapor is heavier than air, and can travel along the
ground to nearby sources of ignition such as electrical motors,
pilot lights, and hot or running engines. Vapors ignited by an
ignition source can flash back to the fuel container, resulting in
an explosion, fire, serious or fatal injuries, and extensive
property damage.
Mixing Instructions
Stored fuel ages. Do not mix more fuel than you expect to use in 30
days or 90 days when a fuel stabilizer is added.
1. Fill an approved fuel container
with half of the required
amount of gasoline.
2. Add the proper amount of
two-stroke oil to gasoline.
3. Close container and shake to
mix oil with gasoline.
4. Add remaining gasoline, close
fuel container, and remix.
Fuel to Oil Mix – 50:1 Ratio
US Metric
Gas Oil Gas Oil
gal. fl.oz. L cc
12.65100
2 5.2 10 200
51325500
SRM-2120 OPERATION
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Spilled fuel is a leading cause of hydrocarbon emissions. Some
locations may require the use of automatic fuel shut-off containers to
reduce fuel spillage.
Storage - Fuel storage laws vary by locality. Contact your local government
for the laws affecting your area. As a precaution, store fuel in an approved,
airtight container. Store in a well-ventilated, unoccupied building, away from
sparks and flames.
• Empty the fuel tank prior to storing the unit. Return unused fuel to an
approved fuel storage container.
Stored two-stroke fuel can separate. ALWAYS shake fuel container
thoroughly before each use.
Used oil and gasoline, and soiled towels are hazardous waste
materials. Disposal laws vary by locality.
Starting Cold Engine
The attachment will operate immediately when the engine
starts, and could result in possible serious injury. Keep
movable parts of the attachment away from objects that could
become entangled or thrown, and surfaces that could cause
loss of control.
1. Stop Switch
Move stop switch button (A)
forward, away from the STOP
position.
A
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2. Choke
Move choke lever (B) to COLD
START ( ) position.
3. Purge Bulb
Pump purge bulb (C) until fuel is
visible and flows freely in the
clear fuel tank return line. Pump
bulb an additional four or five
times.
4. Recoil Starter
Lay the unit on a flat area and
keep movable attachment parts
clear of all obstacles. Firmly
grasp throttle handle and throttle
trigger lockout with left hand and
fully depress throttle trigger to
wide open position. Rapidly pull
recoil starter handle/rope (D) until engine fires (or maximum two to three
pulls).
5. Choke
After engine fires (or two to three pulls), move choke (B) to the RUN ( )
(open) position. Firmly grasp throttle handle and throttle trigger lockout
with left hand and fully depress throttle trigger to wide open position. Pull
starter handle/rope until engine starts and runs. Release throttle trigger
and allow unit to warm up at idle for several minutes.
Note: If engine does not start with choke in “RUN” position after two
to three
pulls, repeat instructions 2 - 5.
6. Throttle Trigger
After engine warm-up, grip throttle handle and support handle. Depress
the throttle trigger lockout, and gradually depress throttle trigger to
increase engine RPM to operating speed.
C
B
D
SRM-2120 OPERATION
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Starting Warm Engine
The starting procedure is the same as Cold Start except DO NOT close the
choke, and do not hold throttle trigger fully depressed.
The attachment should not move at idle, otherwise serious
personal injury may result.
Note: If attachment moves, readjust carburetor according to
“Carburetor Adjustment” instructions in this manual or see
your ECHO Dealer.
1. Stop Switch
Move stop switch button (A)
forward away from the STOP
position.
2. Purge Bulb
Pump purge bulb (C) until fuel is
visible in the clear fuel return
line. Pump bulb an additional
four or five times.
A
C
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3. Recoil Starter
Lay the unit on a flat area and
keep movable attachment parts
clear of all obstacles. Firmly grip
throttle handle and throttle
trigger lockout with left hand.
Rapidly pull recoil starter
handle/rope (D) until engine
fires.
Note: If engine does not start after two to three pulls, use Cold Start
Procedure.
Stopping Engine
1. Throttle
Release throttle trigger and
allow engine to return to idle
before shutting off engine.
2. Stop Switch
Move stop switch button (A)
backward to STOP position.
If engine does not stop when stop switch is moved to STOP
position, close choke - COLD START position - to stall engine.
Have your ECHO dealer repair stop switch before using unit
again.
Applications
Always hold throttle handle with right hand and support handle
with left hand, placing unit on right side of body.
Do not install blades on GT (Curved Shaft) trimmers.
D
A
SRM-2120 OPERATION
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Operating Techniques – Nylon Line Head
Nylon line heads may be used for trimming, scything, edging, and scalping
of grass and light weeds.
Units with Speed Feed
®
line heads only: To advance trimmer line, tap
trimmer head against the ground while the head is turning at normal
operating speed.
Trimming
Feed the spinning line into the material to be cut. Tilt the line head to one
side to direct cutting debris away from you:
• SRM/DSRM/PAS/DPAS/SB/TX/C/T (Straight shaft, counter-clockwise line
head rotation) Models: Tilt the cutting head down on the right side while
cutting to direct cutting debris away from operator. Feed the line gradually
into the material you wish to cut, avoiding contact with fences or other
barriers.
• GT Models: Tilt cutting head to the left while cutting to direct debris away
from the operator.
Scything
Scything - Swing the cutting head in a level arc, gradually feeding the line
into the material being cut. Move forward with each arc to cut a swath.
Width of cutting swath depends on arc. Use a larger arc for a wider swath,
or a smaller arc for a narrow swath. Keep line head tilted to direct cutting
debris forward or away from you.
Edging and Scalping
Both of these are done with the nylon line cutting head tilted at a steep
angle. Scalping is removing top growth, leaving the earth bare. Edging is
trimming the grass back where it has spread over a pavement or driveway.
During both edging and scalping, hold the unit at a steep angle in a position
where the debris, and any dislodged dirt and stone, will not come back
towards you even if it ricochets off the hard surface.
General
• Debris flows in direction of line head rotation. Change line head position
to assure debris flow is directed away from operator.
• Keep cutting line away from wire fences to avoid entanglement.
• Operate trimmer only with cutting head below knee height.
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Operating Techniques - Metal or Plastic Blade
Brushcutter blades may be used to cut and trim a wide variety of materials.
Refer to the blade selection section for determining the correct blade for the
application.
Scything (3-, 8-, and 80-tooth weed/grass, and brush blades)
• To cut large sections of field grass and weeds swing the cutting head in a
level arc, gradually feeding the blade into the material being cut. Adjust
throttle speed according to your work.
• Do not swing the main pipe with arms. Turn hips to swing
the blade horizontally from right to left, and cut weeds on the
left side of the blade.
• Do not scythe back and forth as the grass may scatter and
kickback may occur easily.
• Tilt blade left by 5 to 10 degrees so that cut grasses will
push left, making progress easier.
• Move forward with each arc to cut a swath.
• Width of cutting swath depends on arc. Use a larger arc
for a wider swath, or a smaller arc for a narrow swath.
Suggested cutting width is about 1.5 m (4.9 ft).
• When scything large brush up to 12.7 mm (0.5 in.)
diameter from right to left, avoid cutting with highlighted
section.
Reaction Forces
The cutting attachment will continue to rotate even after
the throttle is released, maintain control of the unit until it
has come to a complete stop.
Blade thrust may occur when the spinning blade contacts
an object that it does not immediately cut. Following
proper cutting techniques will prevent blade thrust.
Blade thrust can be violent enough to cause the unit and/or
operator to be propelled in any direction, and possibly lose
control of the unit.
SRM-2120 OPERATION
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Blade thrust can occur without warning if the blade snags,
stalls or binds.
Blade thrust is more likely to occur in areas where it is
difficult to see the material being cut.
Push or Pull - Kickout
During normal use, operating a brushcutter with a circular metal blade can
produce sudden strong reaction forces that are difficult to control. Strong
reaction forces can cause a loss of balance or loss of control of the
equipment, resulting in serious injury to operator and bystanders.
Understanding what causes these reactive forces may help you to avoid
them, and can help you to maintain control of the equipment if you
experience a sudden reaction during cutting. Reactive forces occur when
the force being applied by the cutting teeth of a blade meet resistance, and
some of the cutting force is directed back toward the equipment. The
greater the cutting force or the amount of resistance, the greater the
reactive force.
Push and Pull Forces
Push and pull forces are reactive forces that push the
equipment directly toward the operator, or that pull the
equipment directly away from the operator. These forces are
the result of cutting on the sides of the blade. The direction of
the force depends on the side of the blade being used, and
the direction of blade rotation at the point of contact. The
reactive force is in the opposite direction of blade rotation at
the contact point, regardless of where the contact is being
made. These types of reactive forces are also called “Blade
Thrust.”
A blade turning counterclockwise will cause the equipment
to pull away from the operator if the point of cutting
resistance is on the left side of the blade. See illustration. If
the point of cutting resistance is on the right side of the
blade, the equipment will push back toward the operator. In
both examples, the reactive force is in the opposite
direction of blade rotation at the contact point where
resistance occurs.
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Kickout
Kickout is also a reactive force caused by
resistance to cutting, but the direction of blade
thrust is lateral (to the left or right of the blade),
instead of forward or back toward the operator. In
most cases, Push, Pull, and Kickout can be
reduced or eliminated by:
• Using the correct blade for the cutting job
• Using properly sharpened blades
• Applying consistent, even force to the blade during
the cut
• Avoiding obstacles and ground hazards
• Using extra care when cutting harder materials
such as extremely dry brush, saplings, and small
trees
• Cutting from a stable, secure position
Blade Cutting Problems
Binding - Blades may bind in the cut if dull or
forced. Binding can damage blade, and result in
blade breakage or injury from fragments and flying
debris. If a blade binds in a cut, don’t try to get it
out by applying “up and down” force to pry the cut
open. Applying prying force to the blade can bend
the blade, and result in blade failure and injury.
To free a blade that is bound in the cut, stop the
unit, and support the trimmer or brushcutter to keep stress off the blade.
Push the tree away from the entry point of the cut to open the cut, and pull
the blade directly away from the cut in a straight-line motion. Use caution
when releasing the tree to avoid being struck by spring-back or falling.
Inspect the blade for damage before proceeding. Sharpen teeth if dull, or
replace blade if cracked, bent, missing teeth, or otherwise damaged.
To prevent binding:
• Keep blades sharp
• Avoid excessive pressure during cutting
• Do not exceed cutting capacity of blade
• Do not use blades with damaged or missing cutting teeth
• Do not tilt blade during cutting
SRM-2120 MAINTENANCE
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MAINTENANCE
Moving parts can amputate fingers or cause severe injuries.
Keep hands, clothing and loose objects away from all openings.
Always stop unit, disconnect spark plug or remove battery, and
make sure all moving parts have come to a complete stop
before removing obstructions, clearing debris, or servicing unit.
Allow the unit to cool before performing maintenance or
adjustments. Wear gloves to protect hands from sharp edges
and hot surfaces.
Operating a poorly maintained unit can result in serious injuries
to operator or bystanders. Always follow all maintenance
instructions as written, otherwise serious personal injury can
result.
Your unit is designed to provide many hours of trouble free service. Regular
scheduled maintenance will help your unit achieve that goal. If you are
unsure or are not equipped with the necessary tools, we recommend that
you take your unit to a Servicing Dealer for maintenance. To help you
decide whether you want to do it yourself or have the dealer do it, each
maintenance task has been graded. If the task is not listed, see your Dealer
for repairs.
The use of emission control components other than those specifically
designed for this unit is a violation of federal law.
Skill Levels
Level 1 = Easy to do. Common tools may be required.
Level 2 = Moderate difficulty. Some specialized tools may be required.
Level 3 = See your dealer.
Click HERE or go to http://www.echo-usa.com/products/maintenance-kit
or
https://www.shindaiwa-usa.com/you-can.aspx
MAINTENANCE SRM-2120
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Maintenance Intervals
Note: Time intervals shown are maximum. Actual use and your
experience will determine the frequency of required
maintenance.
COMPONENT / SYSTEM
MAINTENANCE
PROCEDURE
SKILL
LEVEL
Daily or Before Use
Air filter
Inspect / Clean*
1
Choke shutter
Fuel system
Inspect
3
Cooling system Inspect / Clean 2
Recoil starter rope Inspect / Clean*
1
Screws / nuts / bolts Inspect / Tighten / Replace*
Blade Inspect / Replace* 1
Every Refuel
Fuel system
Inspect
3
1
3 Months
Air filter Replace*
1
Fuel filter
Inspect*
Fuel cap gasket
Spark plug
Inspect / Clean / Replace*
Muffler spark arrester
2
Cylinder exhaust port Inspect / Clean / De-carbon
Drive shaft
(flex cable models)
Grease
1
Gear housing (certain models)
Grease
2
Yearly
Fuel filter Inspect / Replace*
1
Fuel cap gasket Replace*
SRM-2120 MAINTENANCE
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Maintenance Procedure Notes:
1
Apply lithium-based grease every 25 hours of use.
2
Apply lithium-based grease every 50 hours of use.
3
Low evaporative fuel tanks do not require regular maintenance to maintain
emission integrity.
* Replacement is recommended based on the finding of damage or wear
during inspection.
Air Filter
Level 1.
Parts required: Tune-up kit.
1. Close choke (COLD START position). This prevents dirt from entering
the carburetor throat when the air filter is removed. Brush accumulated
dirt from air cleaner area.
2. Remove air filter cover. Brush
dirt from inside cover.
3. Replace filter if it is damaged,
fuel soaked, very dirty, or the
rubber sealing edges are
deformed.
• Lightly brush debris from filter.
• Soak heavily soiled filters in
water/detergent solution to
loosen dirt, then brush lightly.
• Rinse with clean water and allow to dry completely before reuse.
4. Install air filter in air filter case.
5. Install air filter cover.
MAINTENANCE SRM-2120
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Fuel Filter
Level 1.
Parts required: Tune-up kit.
Fuel is flammable. Use extreme care when mixing, storing or
handling, or serious personal injury may result.
1. Use a clean cloth to remove loose dirt from around fuel cap and empty
fuel tank.
Do not damage fuel line while removing fuel filter from tank or line.
2. Pull the fuel filter from the tank.
3. Do not remove the wire coil
clamp to remove the fuel filter.
Pinch the fuel filter with the
fingers on one hand and the
fuel line with the other hand.
Pull and twist slightly to
separate.
4. Install the new filter with the
reverse action.
Note: Federal EPA regulations require all model year 2012 and
later gasoline powered engines produced for sale in the
United States to be equipped with a special low permeation
fuel supply hose between the carburetor and fuel tank. When
servicing model year 2012 and later equipment, only fuel
supply hoses certified by EPA can be used to replace the
original equipment supply hose. Fines up to $37,500 may be
enforced for using a non-certified replacement part.
SRM-2120 MAINTENANCE
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Spark Plug
Level 2.
Parts required: Tune-up kit.
Use only NGK BPM8Y spark plug (BPMR8Y in Canada) otherwise
severe engine damage may occur.
1. Remove spark plug and check
for fouling, worn and rounded
center electrode.
2. Clean the plug or replace with a
new one. DO NOT sand blast to
clean. Remaining sand will
damage engine.
3. Adjust spark plug gap by
bending outer electrode.
4. Tighten spark plug to 130-170 kgf•cm (112-150 lbf•in).
Cooling System
Level 2.
To maintain proper engine operating temperatures, cooling air must
pass freely through the cylinder fin area. This flow of air carries
combustion heat away from the engine.
Overheating and engine seizure can
occur when:
• Air intakes are blocked,
preventing cooling air from
reaching the cylinder.
• Dust and grass build up on the
outside of the cylinder. This build
up insulates the engine and
prevents the heat from leaving.
Removal of cooling passage
blockages or cleaning of cooling fins
is considered normal maintenance. Any failure attributed to lack of
maintenance is not warranted.
0.65 mm (0.026 in.)
MAINTENANCE SRM-2120
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1. Remove spark plug lead.
2. Close choke (COLD START
[ ] position). This prevents dirt
from entering the carburetor
throat when the air filter is
removed. Remove air cleaner
cover (A).
3. Remove engine cover (B).
DO NOT use a metal scraper to remove dirt from the cylinder fins.
4. Use a plastic or nylon bristle
brush to remove dirt from the
cylinder fins.
5. Remove ignition wires from clip
for cleaning.
6. Remove grass and leaves from
the grid between the recoil
starter and fuel tank.
7. Assemble components in
reverse order.
B
A
SRM-2120 MAINTENANCE
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Exhaust System
Spark Arrester Screen
Level 2.
Parts required: Spark arrester screen, gasket.
1. Remove spark plug lead and engine cover.
2. Place piston at Top Dead Center (TDC) to prevent carbon/dirt from
entering cylinder.
3. Remove spark arrester screen
cover (C), gasket (D), and
screen (E), from muffler body.
4. Clean carbon deposits from
muffler components.
Note: When cleaning carbon
deposit, be careful not to
damage the catalytic
element inside muffler.
5. Replace screen if it is cracked, plugged, or has holes burned through.
6. Assemble components in reverse order.
Exhaust Port Cleaning
Level 2.
Parts required: Heat shield (as needed).
1. Remove spark plug lead from spark plug, and remove engine cover.
2. Place piston at top dead center.
Remove muffler (A) and heat
shield (B).
Never use a metal tool to scrape carbon from the exhaust port. Do
not scratch the cylinder or piston when cleaning the exhaust port. Do
not allow carbon particles to enter the cylinder.
D
E
C
AB
MAINTENANCE SRM-2120
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3. Use a wood or plastic scraping
tool to clean deposits from
cylinder exhaust port (C).
4. Inspect heat shield, and replace if damaged.
5. Install heat shield and muffler.
6. Tighten muffler mounting bolts (or nuts) to 90-110 kgf•cm
(80-95 lbf•in).
7. Install engine cover and attach spark plug lead.
8. Start engine and warm to operating temperature.
9. Stop engine and tighten mounting bolts (or nuts) to specifications.
Carburetor Adjustment
Level 2.
Engine Break-In
New engines must be operated a minimum duration of two tanks of fuel
break-in before carburetor adjustments can be made. During the break-in
period your engine performance will increase and exhaust emissions will
stabilize. Idle speed can be adjusted as required.
High Altitude Operation
This engine has been factory adjusted to maintain satisfactory starting and
durability performance up to 335 m (1,100 ft.) above sea level (ASL)
(96.0 kPa). To maintain proper engine operation and emission compliance
above 335 m (1,100 ft.) ASL the carburetor may
need to be adjusted by an
authorized service dealer.
If the engine is adjusted for operation above 335 m (1,100 ft.) ASL,
the carburetor must be re-adjusted when operating the engine below
335 m (1,100 ft.) ASL, otherwise severe engine damage may result.
C
C
SRM-2120 MAINTENANCE
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Note: Every unit is run at the factory and the carburetor is set in
compliance with emission regulations. Carburetor
adjustments, other than idle speed, must be performed by an
authorized dealer.
The cutting attachment may be moving during carburetor
adjustments.
Wear your protective equipment and observe all safety
instructions.
For units equipped with a clutch, be sure the cutting
attachment stops moving when the engine idles.
When the unit is turned off, make sure the cutting
attachment has stopped before the unit is set down.
1. Check idle speed and reset if
necessary. If a tachometer is
available, idle speed screw (A)
should be set to the
specifications found on
“Specifications” page of this
manual. Turn idle screw (A)
clockwise to increase idle
speed; counterclockwise to
decrease idle speed.
Turn idle screw (A):
• Clockwise to increase idle
speed
• Counterclockwise to
decrease idle speed
When carburetor adjustment is completed, the cutting
attachment should not move at idle, otherwise serious personal
injury may result.
A
A
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Lubrication
Level 1.
Parts required: Lithium-based grease.
Gear Case
Gear cases without grease plug (A) do not require lubrication.
1. Clean all loose debris from gear
case.
2. Remove plug (A), if required,
and check level of grease.
3. Add grease if necessary. Do not
over-fill.
Drive Shaft (Flex Cable Only)
1. Loosen screw (B) and remove
locating screw (C). Pull gear
case and shield from drive shaft
housing.
2. Pull flexible cable (D) from the
drive shaft housing, wipe clean
and re-coat with 15 ml (0.5 oz.)
of grease.
3. Slide the flexible cable (D) back
in the drive housing. DO NOT
get dirt on the flex cable.
4. Install the gear housing and
shield assembly.
A
C
B
D
SRM-2120 MAINTENANCE
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Sharpening Metal Blades
Metal blades are very sharp and can cause severe injuries, even
if unit is off and blades are not moving. Avoid contact with
blades. Wear gloves to protect hands.
Several styles of metal blades are approved for use on the Brushcutter. The
8-tooth blade can be sharpened during normal maintenance. The clearing
blade and 80-tooth blade require professional service.
Before sharpening, closely inspect
blade for cracks (look at the bottom
of each tooth and the center
mounting hole closely), missing
teeth and bending. If any of these
problems are discovered, replace
the blade.
When sharpening a blade, always
remove the same amount of
materials from each tooth to
maintain balance. A blade that is not
balanced will cause unsafe handling
due to vibration and can result in
blade failure.
If an electric grinder is used, use care not to overheat teeth, do not
allow tips/tooth to glow red or turn blue. Do not place blade in cooling
water. This will change the temper of the blade and could result in
blade failure.
5. File each tooth at a 30 degree
angle a specific number of
times, e.g., four strokes per
tooth. Work your way around
the blade until all teeth are
sharp.
30º
30º
TROUBLESHOOTING SRM-2120
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6. DO NOT file the ‘gullet’ (radius)
of the tooth with the flat file. The
radius must remain. A sharp
corner will lead to a crack and
blade failure.
7. After sharpening teeth, check
each tooth radius for evidence
of a square (sharp) corner. Use
the round (rat tail) file to renew
the radius.
TROUBLESHOOTING
Fuel vapors are flammable and can cause fire and/or explosion.
Never test for ignition spark by grounding spark plug near
cylinder plug hole, otherwise serious personal injury can result.
ENGINE PROBLEM TROUBLESHOOTING CHART
Problem Check Status Cause Remedy
Engine
starts hard
or
Engine
does not
start
Fuel at
carburetor
No fuel at
carburetor
Fuel strainer or
fuel line
obstructed
Clean or replace
See your dealer
Fuel at
cylinder
No fuel at
cylinder
Carburetor See your dealer
Muffler wet
with fuel
Fuel mixture too
rich
Open choke
Clean or replace
air filter
Adjust carburetor
See your dealer
30º
CUTTING
TOOTH
AREA
CUTTING
TOOTH
RADIUS
GULLET
(RADIUS)
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Engine
starts hard
or
Engine
does not
start
Spark at
end of plug
wire
No spark
STOP switch
OFF - Electrical
problem -
Interlock switch
Turn switch to ON
See your dealer
Spark at
plug
Incorrect gap -
Covered with
carbon - Fouled
with fuel - Plug
defective
Adjust to
0.65 mm
(0.026 in.)
Clean or replace
plug
Engine
runs, but
dies
or
Engine
does not
accelerate
properly
Air filter Air filter dirty Normal wear Clean or replace
Fuel filter
Fuel filter
dirty
Contaminants or
residue in fuel
Replace filter or
replace fuel
Fuel vent
Fuel vent
plugged
Contaminated
fuel
Clean or replace
Spark plug
Plug dirty or
worn
Normal wear
Clean and adjust
or replace
Carburetor
Improper
adjustment
Vibration Adjust
Cooling
system
Cooling
system dirty
or plugged
Extended
operation in dirty
or dusty locations
Clean
Spark
arrester
screen
Spark
arrester
screen
plugged
Normal wear Replace
Engine
does not
crank
N/A
Internal engine
problem
See your dealer
ENGINE PROBLEM TROUBLESHOOTING CHART
Problem Check Status Cause Remedy
STORAGE SRM-2120
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STORAGE
During operation the muffler or catalytic muffler and
surrounding cover become hot. Always keep exhaust area clear
of flammable debris during transportation or when storing,
otherwise serious property damage or personal injury may
result.
Long-Term Storage (Over 30 Days)
Do not store your unit for a prolonged period of time (30 days or longer)
without performing protective storage maintenance which includes the
following:
Do not store in enclosure where fuel fumes may accumulate or
reach an open flame or spark.
1. Store unit in a dry, dust-free place, out of the reach of children.
2. Place the stop switch in the OFF position.
3. Remove accumulation of grease, oil, dirt and debris from exterior of
unit.
4. Perform all periodic lubrication and services that are required.
5. Tighten all the screws and nuts.
6. Drain fuel tank completely. Press purge bulb six to seven times to
remove remaining fuel from carburetor then drain the tank again. Close
choke, start and run the engine until it stops due to lack of fuel.
7. Allow engine to cool. Remove the spark plug lead from the spark plug.
Remove the spark plug. Pour 7 cc (0.25 oz.) of fresh, clean, two-stroke
engine oil into the cylinder through the spark plug hole.
8. Pull the recoil starter handle two to three times to distribute the oil
inside the engine.
9. Observe the piston location through the spark plug hole. Pull the recoil
handle slowly until the piston reaches the top of its travel and leave it
there.
10. Install the spark plug. Connect the spark plug lead to the spark plug.
SRM-2120 SPECIFICATIONS
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SPECIFICATIONS
MODEL SRM-2120
Length
(without cutter head)
1,775 mm (69.9 in.)
Width 244 mm (9.6 in.)
Height 329 mm (13.0 in.)
Weight - dry)
(without cutter head)
4.4 kg (9.7 lb.)
Engine Type
Air -cooled, two-stroke, single cylinder gasoline
engine
Bore 32.2 mm (1.27 in.)
Stroke 26.0 mm (1.02 in.)
Displacement
21.2 cc (1.29 in.
3
)
Exhaust
Spark arrester muffler or spark arrester muffler
with catalyst
Carburetor Diaphragm with purge pump
Ignition System
Flywheel magneto, capacitor discharge ignition
type
Spark Plug
NGK BPM8Y (BPMR8Y in Canada)
Gap 0.65 mm (0.026 in.)
Fuel Mixed (gasoline and two-stroke oil)
Fuel/Oil Ratio 50:1
Gasoline
Use 89 Octane unleaded. Do not use fuel
containing methyl alcohol, more than 10% ethyl
alcohol or 15% MTBE. Do not use alternative
fuels such as E20 or E85.
Oil
ISO-L-EGD (ISO/CD 13738) and J.A.S.O.
M345- FD, two-stroke, air-cooled engine oil.
Fuel Tank Capacity 0.38 L (12.8 US fl. oz.)
Starter System Automatic rewind starter
Clutch Centrifugal type
PRODUCT REGISTRATION SRM-2120
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PRODUCT REGISTRATION
Thank you for choosing ECHO Power Equipment
Please go to http://www.echo-usa.com/Warranty/Register-Your-ECHO to
register your new product on-line. It's FAST and EASY! NOTE: Your
information will never be sold or misused by ECHO Incorporated.
Registering your purchase enables us to contact you in the unlikely event of
a service update or product recall, and verifies your ownership for warranty
consideration.
If you do not have access to the Internet, you can complete the form below
and mail to:
ECHO Incorporated, Product Registration, PO Box 1139,
Lake Zurich, IL 60047.
Vibration Reduction
Systems
Without
Operating Rod 25.0 mm (1.0 in.) diameter aluminum tube
Drive Shaft 6.0 mm (0.24 in.) flexible shaft
Gear Case Ratio 1.62:1
Rotating Direction Counterclockwise (viewed from top)
Cutter Head
Rapid Loader
®
Head (2-line)
Handle
Front - D-loop type without anti-vibration
Rear - Plastic grip
Shoulder Harness Optional
Idle Speed 3,000 RPM
Clutch Engagement
Speed
4,200 RPM
Wide Open Throttle Speed 10,000 RPM
MODEL SRM-2120
SRM-2120 PRODUCT REGISTRATION
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ECHO Incorporated
NOTES SRM-2120
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NOTES
SRM-2120 NOTES
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