Troy-Bilt AH721 Owner's Manual

®

Hedge Trimmer AH721

Operator’s Manual

TABLE OF CONTENTS

Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Know Your Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Maintenance & Repair Instructions . . . . . . . . . . . . . . . . . . . . . . . . .5

Cleaning and Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

SAVE THESE INSTRUCTIONS

For service call 1-800-345-8746, or 1-800-668-1238 in Canada to
obtain a list of authorized service dealers near you. For more details
about your unit, visit our website at www.trimmerplus.com.

If you have difficulty assembling this product or have any questions
regarding the controls, operation or maintenance of this unit, please
call the Customer Support Department.

PROOF OF PURCHASE WILL BE REQUIRED FOR WARRANTY
SERVICE.

Service on this unit both within and after the warranty period should
be performed only by an authorized and approved service dealer.

All information, illustrations, and specifications in this manual are based
on the latest product information available at the time of printing. We
reserve the right to make changes at any time without notice.

Copyright© 2011 MTD SOUTHWEST INC, All Rights Reserved.

769-07497 P00 12/11

AFETY

S

The purpose of safety symbols is to attract your attention to
possible dangers. The safety symbols, and their explanations,
deserve your careful attention and understanding. The safety
warnings do not by themselves eliminate any danger. The
instructions or warnings they give are not substitutes for proper
accident prevention measures.

SYMBOL MEANING

DANGER:

Failure to obey a safety DANGER signal WILL result in
serious injury or death to yourself or to others.

WARNING:

ailure to obey a safety WARNING signal CAN result in

F
serious injury to yourself or to others.

CAUTION:

Failure to obey a safety CAUTION signal MAY result in
property damage or injury to yourself or to others.

NOTE: Advises you of information or instructions vital to the

operation or maintenance of the equipment.

Read the Operator’s Manual and follow all warnings and safety
instructions. Failure to do so can result in serious injury to the operator
and/or bystanders.

1-800-345-8746 IN U.S. OR 1-800-668-1238 in CANADA

• IMPORTANT SAFETY INSTRUCTIONS •

Signals an EXTREME hazard.

Signals a SERIOUS hazard.

Signals a MODERATE hazard.

READ ALL INSTRUCTIONS BEFORE OPERATING

WARNING:

rules. Please read these instructions before operating the unit in
order to ensure the safety of the operator and any bystanders.
Please keep these instructions for later use.

• Carefully read and understand the operator's manual of the unit
that powers this attachment.

• Read the instructions carefully. Be familiar with the controls and
proper use of the unit.

• Do not operate this unit when tired, ill or under the influence of
alcohol, drugs or medication.

• Children must not operate the unit. Teens must be accompanied
and guided by an adult.

• All guards and safety attachments must be installed properly
before operating the unit.

• Inspect the unit before use. Replace damaged parts. Check for
fuel leaks. Make sure all fasteners are in place and secure.
Replace parts that are cracked, chipped, or damaged in any
way. Do not operate the unit with loose or damaged parts.

• Carefully inspect the area before starting the unit. Remove all
debris and hard or sharp objects such as glass, wire, etc.

• Be aware of the risk of injury to the head, hands and feet.

• Clear the area of children, bystanders and pets; keep them
outside a 50-foot (15 m) radius, at a minimum. Even then, they are
still at risk from thrown objects. Encourage bystanders to wear
eye protection. If you are approached, stop the unit immediately.

When using the unit, you must follow the safety

• Always stop the engine and allow it to cool before filling the
ank. Never remove the fuel tank cap or add fuel when the

t
engine is hot. Always loosen the fuel tank cap slowly to relieve
any pressure in the tank before fueling.

• Always mix and add fuel in a clean, well-ventilated outdoor area

here there are no sparks or flames. DO NOT smoke.

w

• Never operate the unit without the fuel cap securely in place.

• Avoid creating a source of ignition for spilled fuel. Wipe up any

spilled fuel from the unit immediately, before starting the unit.

ove the unit at least 30 ft. (9.1 m) from the fueling source and

M
site before starting the engine. DO NOT smoke.

• Never start or run the unit inside a closed room or building.

Breathing exhaust fumes can kill. Operate this unit only in a well

entilated outdoor area.

v

WHILE OPERATING

• Wear safety glasses or goggles that meet ANSI Z87.1-1989

standards and are marked as such. Wear ear/hearing protection
when operating this unit. Wear a face or dust mask if the
operation is dusty.

• Wear heavy long pants, boots, gloves and a long sleeve shirt. Do

not wear loose clothing, jewelry, short pants, sandals or go
barefoot. Secure hair above shoulder level.

• Make sure the attachment is not in contact with anything before

starting the unit.

• Use the unit only in daylight or good artificial light.

• Use the right tool. Only use this tool for its intended purpose.

• Always hold the unit with both hands when operating. Keep a

firm grip on both handles or grips.

• Do not overreach. Always keep proper footing and balance. Take

extra care when working on steep slopes or inclines.

• Keep hands, face, and feet away from all moving parts. Do not

touch or try to stop moving parts.

• Do not operate the unit faster than the speed needed to do the job.

Do not run the unit at high speed when not in use.

• Use extreme caution when reversing or pulling the unit towards you.

• DO NOT force the unit. It will do a better, safer job when used at

the intended rate.

• Always stop the unit when operation is delayed or when walking

from one location to another.

• If you strike or become entangled with a foreign object, stop the

unit immediately and check for damage. Do not operate before
repairing damage. Do not operate the unit with loose or
damaged parts.

• Use only original equipment manufacturer (OEM) replacement

parts and accessories for this unit, as listed in the Parts List
section of this manual. Use of any other parts or accessories
could lead to serious injury to the user, or damage to the unit,
and void the warranty.

• Keep the unit clean of vegetation and other materials that may

become lodged in the blade.

• If the unit starts to vibrate abnormally, stop the unit immediately.

Inspect the unit for the cause of the vibration. Vibration is
generally an indicator of trouble.

SAFETY WARNINGS FOR GAS UNITS

WARNING:

can explode if ignited. Take the following precautions:

• Store fuel only in containers specifically designed and approved
for the storage of such materials.

2

Gasoline is highly flammable, and its vapors

AFETY

S

OTHER SAFETY WARNINGS

All service, other than the maintenance procedures described in

•
this manual, should be performed by a qualified service dealer.

Before inspecting, servicing, cleaning, storing, transporting or

•
replacing any parts on the unit:

. Stop the unit.

1

2. Make sure all moving parts have stopped.

3. Allow the unit to cool.
. Disconnect the spark plug wire.

4

• The blades become very sharp from use. Always wear heavy
gloves when handling, replacing or cleaning the blades.

• Never store the unit with fuel in the tank, inside a building where
fumes may reach an open flame (pilot lights, etc.) or sparks
(switches, electrical motors, etc.).

• Be sure to secure the unit while transporting.

• Store the unit in a dry place, secured or at a height to prevent
unauthorized use or damage. Keep out of the reach of children.

• Never douse or squirt the unit with water or any other liquid.
Keep handles dry, clean and free from debris. Clean after each
use, see Cleaning and Storage instructions.

• Keep these instructions. Refer to them often and use them to
instruct other users. If you loan this unit to others, also loan
them these instructions.

SAVE THESE INSTRUCTIONS

NOW YOUR UNIT

K

APPLICATIONS

As a hedge trimmer:

Trimming hedges and bushes

•

NO ASSEMBLY TOOLS

EQUIRED

R

Angle

Adjustment

Handle

Adjustment Lever

WARNING:

product. It is not designed to be used with an extension
and using one may cause serious injury.

DO NOT USE an extension boom with this

Blade

Indexing Ring

• SAFETY AND INTERNATIONAL SYMBOLS •

This operator's manual describes safety and international symbols
and pictographs that may appear on this product. Read the
operator's manual for complete safety, assembly, operating and
maintenance and repair information.

SYMBOL MEANING

• SAFETY ALERT SYMBOL

Indicates danger, warning or caution. May be used in
conjunction with other symbols or pictographs.

• WARNING - READ OPERATOR'S MANUAL

Read the operator’s manual(s) and follow all warnings and
safety instructions. Failure to do so can result in serious
injury to the operator and/or bystanders.

• WEAR EYE AND HEARING PROTECTION

WARNING: Thrown objects and loud noise can cause

severe eye injury and hearing loss. Wear eye protection
meeting ANSI Z87.1-1989 standards and ear protection when
operating this unit. Use a full face shield when needed.

• THROWN OBJECTS AND CUTTING BLADES CAN
CAUSE SEVERE INJURY

WARNING: Small objects can be propelled at high

speed, causing injury. Keep away from the blades.

• KEEP BYSTANDERS AWAY

WARNING: Keep all bystanders, especially children

and pets, at least 50 feet (15 m.) from the operating area.

• KEEP HANDS AWAY FROM BLADES.
MOVING BLADES CAN CAUSE SEVERE INJURY.

Do not put hands on blades when starting the engine
or while operating the hedge trimmer attachment.

SPECIFICATIONS*

Approximate Unit Weight (attachment only)..............4.5 lbs. (2.04 kg)

Blade Length ...............................................................22 in. (55.8 cm)

* All specifications are based on the latest product information
available at the time of printing. We reserve the right to make
changes at any time without notice.

ASSEMBLY

WARNING:

damage to the unit, shut the unit off before removing or
installing an attachment.

To avoid serious personal injury and

NOTE: To make installing or removing the attachment easier, place

the unit on the ground or on a work bench.

Installing the Attachment
NOTE: Remove the protective cap and gray spacer from the upper

and lower shafts prior to assembling the attachment.

1. Turn the knob counterclockwise to loosen (Fig. 1).

2. While firmly holding the attachment, push it straight into the EZ­Link™ coupler until the release button snaps firmly into the 90º
hole (Fig. 3).

3. Turn the knob clockwise to tighten (Fig. 1).

CAUTION:

release button is fully snapped into the 90º hole and that the
knob (Fig. 1) is securely tightened. Using the wrong hole
could lead to personal injury or damage to the unit.

Before operating this unit, be sure that the

3

ASSEMBLY

OPERATION

Removing the Attachment

1. Turn the knob counterclockwise to loosen (Fig. 1).

2. Press and hold the release button (Fig. 2).

3. While firmly holding the upper shaft housing, pull the attachment
traight out of the EZ-Link™ coupler (Fig. 3).

s

The EZ-Link™ System

The EZ-Link™ system enables the use of these optional
attachments.

• Edger* • Pole Saw

• Cultivator • Hedge Trimmer*

• Turbo Blower • Straight-shaft trimmer

• Brushcutter* • Curved-shaft trimmer

*DO NOT use this attachment with an electric-powered unit.

WARNING:

read and understand the manual that came with the
attachment. Follow all safety information contained within.

Before you begin using any attachment,

CHECK FLEX SHAFT ENGAGEMENT PRIOR TO USING

1. Start the unit.

2. Briefly engage and release the trigger.

3. Ensure that the attachment is operating.

4. If the attachment is not operating, remove it and repeat the

installation procedure until the attachment operates correctly.

ARNING:

W

body protection to reduce the risk of injury when operating
this unit.

Always wear eye, hearing, hand, foot and

BEFORE OPERATING

1. Grasp the adjustment lever (Fig. 4) and push to unseat the push
pin from the hole in the indexing ring.

2. Rotate the blade to the desired position using the angle

djustment handle.

a

3. Align the adjustment handle pin with the appropriate hole in the
indexing ring.

4. Release the adjustment lever into the indexing hole to secure the
blade at the desired position.

WARNING:

broken, do not operate the unit until they have been
replaced. Failure to do so could result in serious injury.

WARNING:

parts. Any part of body coming in contact with moving
parts could result in serious injury.

WARNING:

the cutting attachment. DO NOT operate on a slope or hilly
incline if there is any chance of losing footing.

If any parts are missing, damaged or

Keep hands and fingers away from moving

If operating the unit on a slope, stand below

90˚ Hole

EZ-Link™

Coupler

90º Hole

Fig. 1

Fig. 2

Knob

Release Button

OPERATING TIPS

• To trim new growth, use a wide sweeping motion, feeding the
blade teeth through the hedge or twigs. Feed the stems directly
into the cutting blade. The most effective cutting is achieved
with a slight downward tilt of the blade.

• Older growth will have thicker stems and will be trimmed easiest
by using a sawing movement.

• Do not try to cut stems that are larger than 7/16 inches (11mm)
thick with the hedge trimmer. Use a non-powered hand saw or
pruning saw to trim large stems.

• Wear gloves when trimming thorny or prickly growth.

• Use a string to help determine the level height of the hedge.
Stretch a length of string along the top of the hedge at the desired
height and trim the hedge just above the level of the string.

• To trim the sides of the hedge, hold the hedge trimmer at the
bottom and sweep upward. Trim the sides of the hedge so that
they will be slightly narrower at the top (Fig. 5).

WARNING:

engine running or blade turning. To avoid serious personal
injury, turn off the engine. Allow the blade to stop before
removing materials wrapped around the blade shaft.

Adjustment Lever

Do not clear away any cut material with the

Indexing Ring

Indexing Holes

Fig. 3

Lower Shaft

Housing

Angle Adjustment Handle

Fig. 4

Upper Shaft

Housing

4

OPERATION

LEANING

C

CLEANING AND STORAGE

Fig. 5

MAINTENANCE

WARNING:

maintenance or repairs while the unit is running. Always
allow the unit to cool before servicing or repairing the unit.
Disconnect the spark plug wire to prevent the unit from
starting accidentally.

NOTE: Some maintenance procedures may require special tools or

skills. If unsure about these procedures, take the unit to a
qualified service dealer. Call 1-800-345-8746, or 1-800-668-
1238 in Canada.

To prevent serious injury, never perform

LUBRICATING THE BLADE

• For easier operation and longer blade life, lubricate the hedge
trimmer attachment blade before and after each use.

• Before lubricating, be sure the powerhead is turned OFF.

• Apply light machine oil along the edge of the top blade strap (Fig. 6).

• If the hedge trimmer attachment requires lubrication during use,
stop the hedge trimmer prior to applying oil. Do not lubricate the
hedge trimmer while the blades are moving. Trimming may be
resumed after lubrication has been completed.

OTHER MAINTENANCE

• The cutting blades are made from high quality hardened steel.
During normal use, they will not require resharpening unless they
become nicked through contact with a wire fence, glass, stones,
bricks or other hard objects. If the nick interferes with operation,
turn the powerhead OFF and use a fine toothed file or
sharpening stone to remove the nick.

• If the unit is dropped, carefully inspect it for damage. If the blade
is bent, the housing is cracked or the handle is broken, contact a
professional service center for repair prior to using the unit.

• Contact with fertilizers and other garden chemicals can greatly
accelerate the corrosion of metal. Do not store the unit on or
adjacent to fertilizers and chemicals.

WARNING:

the unit and allow it to cool before cleaning or maintaining
the unit.

Use a small brush to clean the outside of the unit. Do not use strong

etergents. Household cleaners that contain aromatic oils such as

d
pine and lemon, and solvents such as kerosene, can damage plastic.
Wipe off any moisture with a soft cloth.

Clean the blade with water. Wipe the blade with a light machine oil to
prevent rust.

To avoid serious personal injury, always stop

STORAGE

• Never store a fueled unit where fumes may reach an open flame
or spark.

• Allow the engine to cool before storing.

• Lock up the unit to prevent unauthorized use or damage.

• Store the unit in a dry, well-ventilated area.

• Store the unit out of the reach of children.

Short-term Storage (1-2 weeks)

1. Store the unit in a horizontal position. If this is not possible, store
the unit vertically with the engine at the top.

Long-term Storage

1. Remove the fuel cap, tip the unit and drain the fuel into an
approved container.

2. Start the engine and allow it to run until it stalls. This ensures
that all fuel has been drained from the carburetor.

3. Allow the engine to cool. Remove the spark plug and put 5 drops
of any high quality motor oil into the cylinder. Pull the starter rope
slowly to distribute the oil. Reinstall the spark plug.

4. Thoroughly clean the unit and inspect it for any loose or
damaged parts. Repair or replace damaged parts and tighten
loose screws, nuts or bolts.

Preparing the Unit for Use after Long-term Storage

1. Remove the spark plug and drain all of the oil from the cylinder.

NOTE: Do not use fuel that has been stored for more than 30 days.

Dispose of old fuel according to federal, state and local regulations.

NOTE: To assure product safety and reliability, repairs, maintenance

and adjustments should be performed by a professional service
center using identical replacement parts.

Fig. 6

5