Operator’s Manual
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WARRANTY
MAX performance,MAX Value,MAX Support that’s
Stump Grinder
Enhanced design features come standard
Engineered for the best user experience
Quality metal parts are used instead of plastic
A robust warranty supports all products
OVERALL DIMENSIONS
Budget-friendly prices make it practical
TABLE OF CONTENTS
TABLE OF CONTENTS
SPECIFICATIONS
SAFETY SIGNS
SAFETY
1
2
2
CHECK CONTROLS
CHECK CUTTING TEETH
13
13
CHECK/ADD OIL
13
FILL STUMP GRINDER GASOLINE TANK
13
INSPECT FUEL SYSTEM/CHECK FOR LEAKS
13
LOCKING HANDLE BAR
14
PERSONAL PROTECTION
14
STARTING THE GRINDER (E-START)
14
STARTING THE GRINDER (RECOIL START)
15
STOPPING THE ENGINE
15
GRINDING THE STUMP
15
REFUELING
16
STORING THE MACHINE
16
REMOVE SPARK PLUG
17
START GRINDER EVERY 4 WEEKS
17
PREPARE ENGINE FOR LONG TERM
(SEASONAL) STORAGE IF NEEDED
17
PERFORM REGULAR MAINTENANCE
18
FOLLOW SAFETY RULES
18
PERFORM ENGINE MAINTENANCE
18
INSPECT FUEL SYSTEM / CHECK FOR LEAKS
18
LUBRICATE
18
CHECK AND ADJUST BRAKE
18
BELT TENSION ADJUSTMENT
18
INSTALLING TEETH
19
MAINTENANCE SCHEDULE 20
GENERAL SAFETY RULES
PERSONAL SAFETY
INSPECT YOUR MACHINE
4
4
4
ENGINE SAFETY
5
FUEL SAFETY
5
SPECIFIC SAFETY RULES
5
PRIOR TO STARTING
5
OPERATION SAFETY
5
OWNER/OPERATOR/RENTER TRAINING
6
RENTAL COMPANIES
6
ENGINE INSTRUCTIONS
6
PRODUCT SUITABILITY
6
WARRANTY REGISTRATION
6
WHEELS
LOWER WELDING PUSH ROD
UPPER WELDING PUSH ROD
3
4
6
7
9
10
10
10
10
RUBBER BAFFLE
BASE FOOT
11
11
ABOUT YOUR GRINDER
UNPACHING THE CONTAINER
8
CONTENTS SUPPLIED
TO-SCALE HARDWARE
ASSEMBLY
12
KNOW YOUR MACHINE
13
OPERATION
18
MAINTENANCE
Your new Stump Grinder offers quality construction,
and is easy and safe to operate. With proper use and
care, it is designed to give you many years of depend-
able service.
Prepare to experience the durability to take on any job
with the ease, portability, and convenience of your new
Stump Grinder !
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TABLE OF CONTENTS
SPECIFICATIONS
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SPECIFICATIONS
Engine
Certification(S)
Engine Type
Displacement/ HP
Start
Battery
Brake
Belt
Belts Material
Clutch
Cutting Wheel Dia.
Cutting Wheel Thickness
Carbide Tip Qty.
Tip Holder Material
Carbid Tip Material
Cutting Height
Cutting Depth
Max. Stump Dia.
Rotary Chassis
Max. Rotation Angle
Max. Rotating Distance
Tow Bar
Coupler
Wheelbase
Max. Speed
Front Wheel
Tire
Assembled Weight
Gross Weight
Packing Size
DUCAR Dh420(E)
EPA Phase III, CARB Phase III
Single Cylinder, 4 Stroke, Air-Cooled, OHV
420 cc; 15 HP
E-Start
12 V 20 Ah Lead-Acid
2 x Wheel Lock
2 x V-Belts
Kevlar
Centrifugal Clutch
14 in
0.47 in
12 Pcs
42CrMo
YG11C Alloy
15 in Above Ground
10 in Below Ground
32 in
Yes
65 Degrees
31.5 in
Included
2 in Ball
32 in
Off-Road Only and Max. Speed 15mph
10 in
145/70-6 Tubeless Tyre
303 Ibs
353 Ibs
45 x 30 x 29.5 in
Model SG380
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SAFETY SIGNS
OVERALL DIMENSIONS
The rating plate on your machine may show symbols. These represent important information about the product or instruc-
tions on its use.
SAFETY SIGNS
1154mm
45.4”
2510mm
98.9”
815mm
32”
BRAKE
PERSONAL INJURY HAZARD
Never attempt to use this machine without proper
personal protection
When using this machine,you must wear the following:
Eye protection
Ear and hearing protection
Heavy duty work gloves
Sturdy,non-slip footwear
Heavy duty,tight fitting clothing
Keep hands and feet away.
Contact with rotating teeth will cause serious
personal injury.
NEVER operate without guards and covers in place.
Amputation & Entanglement Hazard
Rotating Cutter
Flying Debris Hazard
Flying debris can travel up to 75 feet.
Flying debris can also bounce off of this shield and
hit nearby objects.
NEVER allow anyone in DANGER ZONE while
grinding.
ALWAYS position machine to protect property
(such as buildings and vehicles) from flying debris.
Rubber shielding is intended to direct discharge to
protect operator's lower extremities.
Wear long pants and closed shoes, as well as eye
and face protection.
Replace if shielding is worn or damaged.
Poisonous Gas Hazard
This product gives off carbon monoxide, a poisonous gas that can kill you.
You CANNOT smell it, see it, or taste it.
NEVER use in enclosed spaces EVEN if you run a fan or open doors
and windows.
Only use OUTSIDE and far away from windows, doors, and vents.
See product manual for more details.
Gasoline is highly flammable and explosive.
NEVER fuel a running or hot engine.
KEEP sources of heat, sparks, and flame away during
refueling.
ALWAYS turn engine off and let cool for at least two
minutes before refueling.
Clean up fuel spills immediately.
Ensure there are no fuel leaks before starting.
DO NOT pump fuel directly into engine at gas station.
Hot exhaust fumes from engine can cause fire.
Position muffler at least 7 feet from combustible
objects, including vegetation and clothing.
Do not change or add to exhaust system, fuel
tanks, or fuel lines.
Fire can result.
NEVER remove guards or shields.
NEVER operate this machine when wearing
loose clothing, scarves, or gloves with large
loose cuffs or holes.
ONLY operate with proper guarding of power
transmission system, including all rotating
shafts, pulleys, belts, & couplings.
Fire / Explosion Hazard Fire Hazard Entanglement Hazard
Flying Debris Hazard
Stones, chips, and debris can cause serious injury
or property damage.
Primary chip discharge is in the direction of the arrow.
However debris can fly 75 ft in any direction out the
chute and bounce off objects and hit operator or
bystanders.
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GENERAL SAFETY RULES
SAFETY
SAFETY
Read this manual and labels affixed to the machine to
understand its limitations and potential hazards.
Always keep hands and feet away from all moving parts
during operation. Moving parts can cut or crush body
parts.
Do not touch parts that might be hot from operation.
Allow parts to cool before attempting to maintain, adjust,
or service.
Do not overreach. Do not operate the machine while
barefoot or when wearing sandals or similar lightweight
footwear. Wear protective footwear that will protect your
feet and improve your footing on slippery surfaces. Keep
proper footing and balance at all times. This enables
better control of the machine in unexpected situations.
Check your machine before starting it. Keep guards in
place and in working order. Make sure all nuts, bolts, etc.,
are securely tightened.
Never operate the machine when it is in need of repair or
is in poor mechanical condition. Replace damaged, miss-
ing, or failed parts before using it. Check for fuel leaks.
Keep the machine in safe working condition.
Do not use the machine if the engine's switch does not
turn it on or off. Any gasoline powered machine that can't
be controlled with the engine switch is dangerous and
must be replaced.
Regularly check to see that keys and adjusting wrenches
are removed from the machine area before starting it. A
wrench or a key that is left attached to a rotating part of
the machine may result in personal injury.
Avoid accidental starting. Be sure the engine's switch is
off before transporting the machine or performing any
maintenance or service on the unit. Transporting or
performing maintenance or service on a machine with its
switch on invites accidents.
If the machine should start to vibrate abnormally, stop
the engine (motor) and check immediately for the cause.
Vibration is generally a warning sign of trouble.
Stay alert, watch what you are doing, and use common
sense when operating the machine.
Always keep hands and feet away from all pinch points.
Be thoroughly familiar with the controls and their proper
operation. Know how to stop the machine and disengage
the controls quickly.
Make sure to read and understand all the instructions and
safety precautions as outlined in the Engine Manufactur-
er's manual packed separately with your unit. Do not
attempt to operate the machine until you fully understand
how to properly operate and maintain the engine and how
to avoid accidental injuries and/or property damage.
If the unit is to be used by someone other than original
purchaser or loaned, rented, or sold, always provide this
manual and any needed safety training before operation.
The user can prevent and is responsible for accidents or
injuries that may occur to themselves, other people, and
property.
Do not permit children to operate this machine at any
time.
Keep children, pets, and other people not using the unit
away from the work area. Be alert and shut off unit if
anyone enters work area. Keep children under the watch-
ful care of a responsible adult.
Do not operate the machine while under the influence of
drugs, alcohol, or any medication that could affect your
ability to use it properly.
Dress properly. Wear heavy long pants, boots, and gloves.
Do not wear loose clothing, short pants, or jewelry of any
kind. Secure long hair so it is above shoulder level. Keep
your hair, clothing, and gloves away from moving parts.
Loose clothes, jewelry, or long hair can be caught in
moving parts.
Protect eyes, face, and head from objects that may be
thrown from the unit. Always wear safety goggles or
safety glasses with side shields when operating.
Do not force the machine. Use the correct machine for
your application. The correct machine will do the job more
efficiently and safer at the rate it was designed.
Wear appropriate hearing protection.
PERSONAL SAFETY
INSPECT YOUR MACHINE
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SAFETY
This machine is equipped with an internal combustion
engine. Do not use on or near any unimproved, forest
covered, or brush covered land unless the exhaust system
is equipped with a spark arrester meeting applicable
local, state, or federal laws.
Never start or run the engine inside a closed area. The
exhaust fumes are dangerous, containing carbon monox-
ide, an odorless and deadly gas. Operate this unit only in a
well-ventilated outdoor area.
Do not tamper with the engine to run it at excessive
speeds. The maximum engine speed is preset by the
manufacturer and is within safety limits. See engine
manual.
Keep a Class B fire extinguisher on hand when operating
this Stump grinder in dry areas as a precautionary
measure.
Fuel is highly flammable, and its vapors can explode if
ignited. Take precautions when using to reduce the
chance of serious personal injury.
When refilling or draining the fuel tank, use an approved
fuel storage container while in a clean, well-ventilated
outdoor area. Do not smoke, or allow sparks, open flames,
or other sources of ignition near the area while adding fuel
or operating the unit. Never fill the fuel tank indoors.
Keep grounded conductive objects, such as tools, away
from exposed, live electrical parts and connections to
avoid sparking or arcing. These events could ignite fumes
or vapors.
Always stop the engine and allow it to cool before filling
the fuel tank. Never remove the cap of the fuel tank or
add fuel while the engine is running or when the engine is
hot. Do not operate the machine with known leaks in the
fuel system.
Never overfill the fuel tank. Fill the tank to no more than
1/2" below the bottom of the filler neck to provide space
for expansion as the heat of the engine can cause fuel to
expand.
Replace all fuel tank and container caps securely and
wipe up spilled fuel. Never operate the unit without the
fuel cap securely in place.
Loosen the fuel tank cap slowly to relieve any pressure in
the tank.
Avoid creating a source of ignition for spilled fuel. If fuel
is spilled, do not attempt to start the engine but move the
machine away from the area of spillage and avoid creating
any source of ignition until fuel vapors have dissipated.
When fuel is spilled on yourself or your clothes, wash your
skin and change clothes immediately.
Store fuel in containers specifically designed and
approved for this purpose.
Store fuel in a cool, well-ventilated area, safely away from
sparks, open flames, or other sources of ignition.
Never store fuel or a machine with fuel in the tank inside
a building where fumes may reach a spark, open flame, or
any other source of ignition, such as a water heater,
furnace, or clothes dryer. Allow the engine to cool before
storing in any enclosure.
Identify hazards and take preventive steps to avoid
accidents and minimize risk. Possible hazards include,
but are not limited to, moving parts, thrown objects,
weight of the machine and components, and the operat-
ing environment.
Thoroughly inspect the area in which you are working,
keeping it clean and free of debris to prevent tripping.
Operate on a flat level ground.
Before starting your chipper shredder: make sure the feed
hopper and cutting housing are empty and free of all
debris, check the oil level, make sure all nuts and bolts
are tight, and check the air pressure in the tires.
Never place any part of your body where it would be in
danger if movement should occur during assembly, instal-
lation, operation, maintenance, repair, or moving.
Keep all bystanders and pets at least 75 feet away. If you
are approached, stop the unit immediately.
ENGINE SAFETY
FUEL SAFETY
SPECIFIC SAFETY RULES
PRIOR TO STARTING
OPERATION SAFETY
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ABOUT YOUR GRINDER
ABOUT YOUR GRINDER
Never attempt to cut an a slope exceeding
15°
Read and follow all instructions and safety precautions
presented throughout this manual. A summary of import-
ant safety information can be found at the end of the
manual. Keep this manual for reference and review. If the
owner of this unit is different than the operator, give a
copy of this manual to any operator to read.
The supplier is constantly improving its products. The
specifications outlined herein are subject to change
without prior notice or obligation. The purchaser and/or
user shall assume liability for any modification and/or
alterations of this equipment from original design and
manufacturer.
Please fill out and submit the warranty registration card
so that we have your contact information for any future
product literature or replacement parts you may need.
Avoid contact with hot fuel, oil, exhaust fumes and hot
surfaces. Do not touch the engine or muffler. These parts
get extremely hot from operation. They remain hot for a
short time after you turn off the unit. Allow the engine to
cool before doing maintenance or making adjustments.
If the machine should start to make an unusual noise or
vibration, immediately shut off the engine, disconnect the
spark plug wire, and check for the cause. Unusual noise or
vibration is generally a warning of trouble.
Use only attachments and accessories approved by the
manufacturer. Failure to do so can result in personal
injury.
Keep the engine and muffler free of grass, leaves, exces-
sive grease or carbon build up to reduce the chance of a
fire hazard.
Never douse or squirt the unit with water or any other
liquid. Keep handles dry, clean and free from debris. Clean
after each use.
Observe proper disposal laws and regulations for gas, oil,
etc. to protect the environment.
When storing the machine, keep it out of reach from
children and those unfamiliar with machine instructions
to operate it. This machine can be dangerous when used
by an untrained user.
All persons to whom you rent/loan this grinder must have
access to this manual and read it. Check the tube on the
side of the unit to make sure a manual is inside. Advise all
persons who will operate the machine to read it. You
should also provide personal instruction on how to safely
operate the grinder and remain available to answer any
questions a renter/borrower might have. If videos are
available, have renter watch training video.
For detailed engine operation and maintenance informa-
tion, always refer to the engine owner's Manual furnished
with the grinder.
OWNER/OPERATOR/RENTER TRAINING
WARRANTY REGISTRATION
RENTAL COMPANIES
ENGINE INSTRUCTIONS
Before using, the user shall determine the suitability of
this product for this intended use and assumes liability
therein.
Your stump grinder can be used to remove many tree
stumps and exposed root systems close to ground level.
By moving the blade in sweeping movements laterally
over the top and front of the stump, you can gradually
grind it away. Make sure you completely read and under-
stand this manual before using the grinder for the first
time. If you have any question, contact your retail or rental
dealer or manufacturer.
Exercise caution when cutting stumps on an incline, as
the machine may shift or slide unpredictably. Never
attempt to cut with the machine uphill or downhill from
you as it may slide toward you or you may fall toward the
machine. Cut only on a slope from the side.
PRODUCT SUITABILITY
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UNPACHING THE CONTAINER
UNPACHING THE CONTAINER
Use the screwdriver and hammer to open all the side locks.
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GASOLINE POWERED
STUMP GRINDER
Model Number:
Package size:
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Gross weight:
GASOLINE POWERED
STUMP GRINDER
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CONTENTS SUPPLIED
CONTENTS SUPPLIED
Your stump grinder comes partially assembled and contains the following:
Verify all component and hardware quantities are correct prior to assembling the Stump grinder.
Engine and Drum1x
1x
1x
1x
Upper welding push rod
Rubber Baffle
Wheels
1x
Lower welding push rod
1x
Tow bar and Guiding wheel
1x
Base Foot
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TO-SCALE HARDWARE
TO-SCALE HARDWARE
Hardware graphics are printed at 1:1 scale for ease of identification. Simply place the hardware over the image in the
tables to verify it is the correct size.
M8 X 20mm
Hex bolt
6X
M8 X 25mm
Hex bolt
5X
M6 X 40mm
Hex bolt
2X
M12 X 55mm
Hex bolt
4X
8
Flat washer
6X
12
Flat washer
8X
14
Flat washer
2X
2X
nut M6
Hex lock
11X
nut M8
Hex lock
4X
nut M12
Hex lock
2X
nut M14
Hex lock
M16 X 360mm
Hex bolt
1X
ASSEMBLY
ASSEMBLY
Fix the wheel on the axle with M14, M8X20 hexagonal
bolts, M8 lock nuts and flat washers 8. (See Figure 1)
Use M16X360 hex bolts and M16 lock nuts to pass
through the upper push rod and connect to the lower push
rod.
Connect the throttle control to the upper push rod with
M6X40 hex bolt and M6 lock nut. (See Figure 3)
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Hex bolt M6 X 40mm2X
Hex bolt M16 X 360mm
1X
Hex lock nut M62X
Hex bolt M12 X 55mm
Flat washer 12
4X
8X
Hex lock nut M124X
Hex bolt M8 X 20mm
Flat washer 8
6X
6X
Hex lock nut M86X
Flat washer 14
2X
Hex lock nut M142X
Figure 1
Figure 3
Wheels
Attach the lower push rod to the body base with M12x55
hex bolt, flat washer 12 and M12 lock nut. (See Figure 2)
Lower welding push rod
Upper welding push rod
Use the square lock pin (12×80) to connect the towing
bar and the guide wheel to the main body of the machine.(
See Figure 4)
Tow bar and Guiding wheel
Figure 2
ASSEMBLY
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Install the rubber baffle to the main body of the machine
with M8X25 hex bolts and M8 lock nuts. (See Figure 5)
Hex lock nut M85X
Hex bolt M8 X 25mm5X
Figure 4
Figure 5
Figure 6
Rubber Baffle
Use the square lock pin (12×80) to connect the base
Foot to the main body of the machine. (See Figure 6)
Base Foot
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KNOW YOUR MACHINE
KNOW YOUR MACHINE
Recoil Starter Handle
Choke Control
Fuel Shut-Off Valve
Throttle Control
Brake Lever
Wheels
Rubber Baffle
Handle Bar
Operator Presence Handle Bar
Cutter Teeth
Engine
Safety Bar
Chassis Lock Lever
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OPERATION
OPERATION
Before starting the engine you will want to make sure you
have completed the following:
Marking Underground Utilities.
• Checking Controls.
• Checking Cutting Teeth.
• Checking/Adding Oil.
• Filling Stump Grinder Gasoline Tank.
• Inspecting Fuel System for Leaks.
• Locking Handle Bar.
• Wearing Personal Protection.
• Trimming Stump with Saw.
• Clearing Area of People and Objects.
• Working During Daylight.
• Each of these procedures is discussed in detail below.
• Gas vapor collection inside enclosures.
• Static electric sparks.
• Sparks from electric wiring, batteries, or running
engines.
• Sources of heat (such as a hot engine or exhaust).
• Open flames, including pilot lights.
All guards are in place and tight.
Operator presence bar switch is free moving.
Inspect tires and rims for looseness, damage, and tire
inflation.
Check the gasoline level in the engine's fuel tank. If
needed, fill tank with fresh unleaded gasoline from a
portable container, after first reading the warnings and
instruction below.
- DO NOT fill the gas tank to the top. Gasoline may spill
when operating on a slope.
- DO NOT overfill the gasoline tank. Allow at least 1" of
empty space below the fill neck to allow for fuel expan-
sion.
#92 gasoline fuel and 10w30 engine oil
A leaking fuel line no matter how small can be the source
of a fire or explosion when starting or operating the
engine.
Gasoline is highly flammable and explosive. Heat, sparks
and flames can ignite gasoline vapors, which can become
widespread during fueling. A flash fire ignition and/or
explosion could result and cause serious injury or death.
The following conditions could result in gasoline ignition/-
explosion:
Inspect fuel system & check for leaks BEFORE starting
grinder.
Check the oil level using the dipstick and add oil as
needed.
Using a funnel, add oil up to the FULL mark o the dipstick
with the recommended oil type for your engine and
expected ambient conditions.
(See engine Owner's Manual for oil type and capacity, and
more detailed oil check/fill instructions).
Inspect cutting teeth for tightness and sharpness. Only
use factory-approved parts for repair.
CAUTION: Add engine crankcase oil. A
new engine is shipped without oil.
You must add the correct amount of oil to
engine crankcase or engine will be dam-
aged beyond repair.
Note: #92 gasoline fuel and 10w30 engine
oil.
Never open oil fill port while engine is
running. Hot oil can spray over face and
body.
Gasoline fire/explosion hazard
Fuel leak hazard
FILL STUMP GRINDER GASOLINE TANK
INSPECT FUEL SYSTEM/CHECK FOR LEAKS
CHECK CONTROLS
CHECK CUTTING TEETH
CHECK/ADD OIL
OPERATION
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Inspect the entire fuel system. Look for: Signs of leaks or
deterioration, chafed or spongy fuel hose, loose connec-
tions, loose or missing fuel hose clamps, damaged gaso-
line tank, or defective gasoline shut-off valve.
If grinder is in an enclosed area and you smell gas, DO NOT
start engine! DO NOT light a match. DO NOT flip on an
electrical switch.
Exit area immediately leaving doors open and call fire
department.
After you have completed the pre-start checking list and
procedures, you are ready to start the grinder.
To start the grinder:
Note: For additional engine starting instructions see your
gasoline engine manual.
• Lock handle in the upright position.
• Place stump grinder into position with cutting wheel
near the front-top edge of the stump.
• Use brake lever on handle to lock the wheel brake.
Note: For tighter brake adjustment, turn knob on top of
brake lever. (See Maintenance & Repair sections for
instructions).
Turm starter OFF to position ON and keep it in this
position until the engine starts.
Move the switch back to position on after the engine has
started.
Do not actuate the electric starter for more than 5
seconds. If the engine does not start, release the ignition
switch and wait 10 seconds before actuating the starter
again.
The following directions details how to start the engine of
your grinder.
• Always wear safety glasses with side shields and a
full-face shield.
• The use of ear plugs or other hearing protection device
is also recommended for persons working within 15-20
feet (5-6.5m) of the running grinder for longer than a
few minutes. Hearing can be damaged from prolonged,
close- range exposure to the type of noise produced by
this grinder.
• Wear long pants to protect legs from sparks, hot engine
and flying debris.
• Never wear jewelry or loose-fitting clothing when start-
ing or operating the grinder or any mechanical device.
Loose or dangling apparel, jewelry or hair can become
entangled in moving parts.
• Neither the machine as a whole nor its internal compo-
nents are intended for use in potential explosive atmo-
spheres.
Use approved protective clothing and approved protective
equipment when using the machine.
Handle is capable of folding when not in use.
Never attempt to use the grinder without
proper protective equipment, particularly
eye protection and a full-face shield.
Stay in the OPERATOR POSITION (Behind
the machine) while actuating controls.
Never leave grinder unattended.
LOCKING HANDLE BAR
STARTING THE GRINDER (E-START)
PERSONAL PROTECTION
Trim Stump with
Saw
Cut or trim the stump preferably
to ground level using a power
saw.
Clear Area
Dig away the earth and remove
any stones near the tree stump or
roots that may interfere with your
work.
Working During
Daylight Hours
Only use the machine in daylight
or in well-lit conditions. Never
operate the grinder after dark.
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OPERATION
Stop the engine using the following steps:
Change direction and swing back the other way until you
feel it reach the other edge of the stump. As you swing to
the side listen to the engine. Provide enough feed to give
it a moderate load. If you hear any belt or clutch squealing
you are pushing to hard. If you can not swing it to the side,
raise the grinder up.
Keep hands and feet away. Contact with wheel rotating
teeth will cause serious personal injury.
You can cut roots off by plunging straight through them.
Stones, chips, and debris can cause serious injury or
property damage.
Debris can fly 75 ft (25m) in any direction out of the
chute. They can bounce off any fixed objects as well and
hit operator, bystanders or breakable objects.
Stones, chips, and debris can cause serious injury or
property damage.
Debris can fly 75 ft (25m) in any direction out of the
chute. They can bounce off any fixed objects as well and
hit operator, bystanders or breakable objects.
• Set/engage the brake.
• Pivot the grinder toward the side of the stump, with a
fairly light touch feed straight into the stump. As soon
as you feed in, start to swing to the side until you feel
the wheel drop off the edge of the stump.
• When grinding larger stumps, chips may begin to build
up under the wheel.
• Release brake and pull machine towards you so that the
"chip pile" is directly under the cutting wheel.
• Drop cutter wheel down on "Chip pile", material will be
discharged from machine area.
• Pull the starter grip lightly until you feel resistance,
then pull briskly. Return the starter grip gently. If the
choke lever was moved to the CLOSED position to start
the engine, gradually move it to the OPEN position as
the engine warms up.
• Press down on handle bar to lift cutter wheel off the
ground.
• Grip throttle control lever and handle bar together in
right hand. Centrifugal clutch will engage and cutter
wheel will begin to rotate.
• While holding blade off ground, release the operator
presence bar. The engine will stop. Wait until the blade
completely stops. Lower the blade so it is resting
against the ground.
• Make sure brake is set before leaving the controls,
particularly if you are on an incline.
• Turn engine switch to OFF position.
• Allow the engine to cool for at least 30 minutes before
releasing brake and moving to storage or transporting. A
hot engine can be a fire hazard.
Flying Debris Hazard
Rotating cutter wheel
Flying Debris Hazard
STARTING THE GRINDER (RECOIL START)
STOPPING THE ENGINE
GRINDING THE STUMP
Cutter wheel
Chip pile
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OPERATION
On these large stumps, DO NOT allow grinder wheels to
drop into stump hole. If a hole is in the way of your
progress, fill it with chips or change position.
• When finished, stop the engine.
• Pull machine away from stump, and rack chips away
from stump.
• Before removing gas cap, turn engine off and allow to
cool for at least two minutes.
Note: A running or hot engine can ignite fuel.
• Remove grinder gasoline cap.
• Add gasoline through the fill opening
• Cool engine before storage.
• Clean the grinder.
• Inspect for worn or damaged parts.
• Choose covered storage location.
• Prevent accidental starting.
• Plan on exercising the engine at least monthly unless
the grinder is prepared for long term storage.
• Clean up gasoline spills / splashes immediately.
• Replace gasoline cap securely before starting engine.
• Store extra gasoline in a cool, dry place in an tightly
sealed container.
• Filling towable units or portable containers at service
stations:
Even if you have a towable unit, avoid static electric
sparking while filling the gasoline tank:
- Use only an portable gasoline container to transfer the
gasoline to the grinder's tank.
- Be aware of safety warning and instructions below for
avoiding static electric caused fires.
- Do not overfill.
- Never fill the grinder's gas tank directly from the fuel
pump. The grinder's tank is not grounded and high velocity
flow from the pump can cause static electricity build-up.
Use an portable container to transfer gas to the grinder's
tank.
- Use a portable container made of metal or conductive
plastic. This is preferred because it dissipates static
charge to ground more readily.
- Never fill a portable gas container while it is sitting
inside a vehicle, trailer, trunk, or pick-up truck bed.
ALWAYS place container on the ground to be filled.
- Keep nozzle in contact with container while filing. Do not
use a nozzle lock-open device.
When you are finished using the grinder and it has cooled,
you must:
Detailed instructions are provided below.
- If possible, move the grinder away from spilled gasoline
on the ground.
- Wipe up spilled gasoline, and wait 5 minutes for excess
gasoline to evaporate before starting engine.
- Gasoline soaked rags are flammable and should be
disposed of properly.
- If gasoline is spilled on your skin or clothes, change
clothes and wash skin immediately.
A static electric spark can explosively ignite gasoline
vapor, resulting in a flash fire that could cause serious
injury or death.
Static electric spark hazard
Stop engine and set brake before leaving
operator's position. KEEP BRAKE
ENGAGED except when changing loca-
tions.
REFUELING
STORING THE MACHINE
Let engine cool for at least 30
minutes before storing. A hot
engine can be a fire hazard.
Cool Engine
Clean Grinder
Clean all grease, dirt, mud and
other foreign matter from the
machine. Touch up paint damage
to prevent rust.
Inspect the machine for worn or
damaged parts and tighten any
nuts or screws that may have
become loose. Pay particular
attention to the cutting teeth.
Inspect Grinder
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OPERATION
• Removing all gasoline from the tank and carburetor OR
• Adding fuel stabilizer to the gasoline (following manu-
facturer's instructions)
• Static electric sparks.
• Sparks from electric wiring, batteries, or running
engines.
• Sources of heat (such as a hot engine or exhaust).
• Open flames, including pilot lights.
Remove spark plug, in order to ensure the grinder cannot
be started in a storage location or y untrained persons or
children.
The grinder should be started regularly. At least every 4
weeks, start the engine and let it run for 10 to 15
minutes.
Monthly exercising of the grinder will dry out any moisture
that has accumulated, lubricate cylinders, and clean out
old gas in the carburetor. Moisture, old gas, and dry
mechanical parts cause deterioration in stored engines.
If you will not be able to start the grinder regularly, you
must prepare the engine for long term storage to prevent
gum deposits from forming and causing malfunction of
the engine.
Prepare engine for long term storage by:
1. Ensure gas tank is full.
2. Add fuel stabilizer to fuel tank.
3. Run engine at least 10 minutes after adding stabilizer
to allow it to enter the fuel system.
4. Shut off engine.
5. Disconnect spark plug wire and remove spark plug.
6. Add one teaspoon oil through spark plug hole.
7. Place rag over spark plug hole and turn starter (or pull
the recoil) a few times to lubricate the combustion cham-
ber.
8. Replace spark plug, but do not reconnect the spark plug
wire.
Gasoline is highly flammable and explosive. Drain the fuel
into an approved container OUTDOORS and far away from
open flame. NEVER store an engine with fuel in the tank
indoors or in poorly ventilated spaces where fuel vapor
can come in contact with
Fuel stabilizer steps:
Gasoline fire / explosion hazard
REMOVE SPARK PLUG
START GRINDER EVERY 4 WEEKS
PREPARE ENGINE FOR LONG TERM
(SEASONAL) STORAGE IF NEEDED
Store the grinder in a location
that is:
Clean and dry
Away from sources of heat, open
flames, sparks, or pilot lights,
even if the grinder's gas tank is
empty. Residual gasoline could
ignite.
Away from extreme high or low
temperatures.
Cover it for extra protection.
Choose a Storage
Location
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• Oil and oil filter changing.
• Air filter check/replacement.
• Spark plug cleaning and replacement.
• Fuel filter check/replacement.
• Fuel tank cleaning.
• Turn off grinder. Always turn off grinder and remove
spark plug or spark plug wire before working on the
engine or grinder to prevent accidental starting.
• Replace guards/shields. Make sure all guards and
shields are replaced after servicing the grinder.
• Burns. Muffler will be hot even after unit is stopped.
Allow unit to cool before servicing.
• Repair. Major service, including the installation or
replacement of parts, should be performed only by a
qualified electrical service technician.
• Replacement parts. If a part needs replacement, only
use factory approved repair parts. Replacement parts
that do not meet specifications may result in a safety
hazard or poor operation of the grinder and will void the
warranty.
• Lock the brake, push down on handle bar so that cutter
wheel is off the ground.
• Push or pull the grinder- if the brake is loose, the wheel
will rotate.
• Unscrew set screw.
• Turn knob clockwise to increase tension or count-
er-clockwise to decrease tension.
• Once you have set the brake to the proper tension,
tighten set screw to lock adjustment knob.
Perform periodic maintenance as directed in this manual
to keep the grinder in safe working condition.
Cutter shaft bearings should be greased.
The cutter shaft bearing is greased by pumping grease
into zerks located on the housing of the bearing. Lubricate
after every 20 hours of use.
Check that the brake is functioning properly.
To adjust braking tension:
Perform engine maintenance as specified in the engine
owner's manual.
Engine maintenance items include:
Note: Belt tension and alignment are inter-related. Do not
adjust one without checking the other.
Inspect the fuel system and check for leaks on a regular
basis.
Look for: signs of leaks or deterioration, chafed or spongy
fuel hose, loose connections, loose or missing fuel hose
clamps, damaged gasoline tank, or defective gasoline
shut-off valve.
Read and follow these safety rules whenever you will be
servicing the grinder:
MAINTENANCE
MAINTENANCE
PERFORM REGULAR MAINTENANCE LUBRICATE
CHECK AND ADJUST BRAKE
BELT TENSION ADJUSTMENT
FOLLOW SAFETY RULES
PERFORM ENGINE MAINTENANCE
INSPECT FUEL SYSTEM / CHECK FOR LEAKS
GREASE SPECIFICATIONS
Soap Type
NLGI Grade
Dropping Point
Additives
Viscosity Index
Lithium Complex
#2
230°C (446°F)
Corrosion and Oxida-
tion inhibitors, EP
optional
80 Minimum
• Remove belt guard.
• Loosen engine base (mount) bolts.
• Loosen lock nuts on tension bolt and alignment bolt.
• Turn tension bolt clockwise to increase belt tension
and counterclockwise to decrease belt tension.
• Check that the pulleys are aligned using a straight
edge. To achieve proper pulley alignment you may need
to adjust the alignment bolt. This bolt will serve as an
adjustment point to counter the tension in the belts,
which may cause the engine pulley to be misaligned
with the cutter wheel pulley. Note: Set screws in pulley
have a torque specification of 25.3kg/m.
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MAINTENANCE
INSTALLING TEETH
• Belt tension is proper when a 2.27kg to 3.18kg force
will deflect the belt 2/5" (1cm) at the midpoint.
• Retighten all loosened nuts and bolts.
• Reassemble belt guard.
• Belt tension is proper when a 2.27kg to 3.18kg force
will deflect the belt 2/5" (1cm) at the midpoint.
• Retighten all loosened nuts and bolts.
• Reassemble belt guard.
Lock nut
Lock nut
Tension bolt
Alignment bolt
90°
90°
2/5"
Among the most critical elements of the stump grinder is
the cutting wheel. It is also the most subject to damage
and wear. In the course of grinding stumps it not only
makes contact with the wood, but also encounters
numerous abrasives and objects in the stump's environ-
ment, such as dirt, stones, large rocks and buried scrap.
The loss and wear of cutting teeth can significantly
impair the efficiency and performance of the stump grind-
er. Therefore, it is important to make frequent inspec-
tions of the condition of all the cutting teeth and to
replace any damaged or worn teeth
Thread in the bolt through the cutter wheel and into the
teeth as shown, then tighten. Bolt should be torque to
60ft/lbs.
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MAINTENANCE
MAINTENANCE SCHEDULE
Before attempting any maintenance, be sure that the engine is shut off, the spark plug wire is
removed, and the engine is cool to the touch!
If a part needs replacement, only use parts that meet the manufacturer's specifications. Replace-
ment parts that do not meet specifications may result in a safety hazard or poor operation of the
grinder.
Daily Each Use
Procedure
10 hours 20 hours 40 Hours
Bearing, Shaft-Grease
Belt Tension-Tension
Bolts-Tightness
Engine
Gasoline-Amount
Safety Switch-Operation
Warning Decals-Legible
Tires, Flaps-Condition
Wires, Cables-Condition
Cutter Teeth-Sharpness
See manual
