769-06523 P00
(12/10)
Operator’s Manual
ST4125
4-Cycle Trimmer
SERVICE INFORMATION
TABLE OF CONTENTS
Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Rules for Safe Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Know Your Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Assembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Oil and Fuel Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Starting/Stopping Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Maintenance and Repair Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Cleaning and Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Troubleshooting Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
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© 2010 MTD SOUTHWEST INC, All Rights Reserved.
DO NOT RETURN THIS UNIT TO THE RETAILER. PROOF OF PURCHASE WILL BE REQUIRED
FOR WARRANTY SERVICE.
For assistance regarding the assembly, controls, operation or maintenance of the unit, please call the
Customer Support Department:
1-877-282-8684
(U.S.) or
1-800-668-1238
(Canada)
Additional information about the unit can be found on our website:
www.cubcadet.com
(U.S.) or
www.cubcadet.ca
(Canada)
For service, please call the Customer Support Department to obtain a list of authorized service dealers
near you. Service on this unit, both within and after the warranty period, should only be performed by an
authorized and approved service dealer. When servicing, use only identical replacement parts.
RULES FOR SAFE OPERATION
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.
NOTE:
Advises you of information or instructions vital to the operation or maintenance of the equipment.
SYMBOL
MEANING
SPARK ARRESTOR NOTE
NOTE: For users on U.S. Forest Land and in the states of California, Maine, Oregon and Washington.
All U.S. Forest Land and the state of California (Public Resources Codes 4442 and 4443), Oregon and
Washington require, by law that certain internal combustion engines operated on forest brush and/or grass-
covered areas be equipped with a spark arrestor, maintained in effective working order, or the engine be
constructed, equipped and maintained for the prevention of fire. Check with your state or local authorities for
regulations pertaining to these requirements. Failure to follow these requirements could subject you to liability
or a fine.
This unit is factory equipped with a spark arrestor.
If it requires replacement, ask your LOCAL
SERVICE DEALER to install the
Accessory Part #753-05444 Muffler Assembly
.
READ ALL INSTRUCTIONS BEFORE OPERATING
• 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 and teens under the age of 15 must not use the unit, except for teens 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. At a minimum, keep all children, bystanders, and pets
outside a 50 feet (15 m) radius; there still may be a risk to bystanders from thrown objects. Bystanders
should be encouraged to wear eye protection. If you are approached, stop the unit immediately.
• Use only 0.105 inch, 2.67 mm diameter original equipment manufacturer replacement line. Never use
metal-reinforced line, wire or rope. These can break off and become dangerous projectiles.
• Squeeze the throttle control and check that it returns automatically to the idle position. Make all
adjustments or repairs before using unit.
SAFETY WARNINGS FOR GAS UNITS
• Store fuel only in containers specifically designed and approved for the storage of such materials.
• Always stop the engine and allow it to cool before filling the fuel tank. Never remove the fuel tank
cap or add fuel when the engine is hot. Always loosen the fuel tank cap slowly to relieve any
pressure in the tank before fueling. Do not smoke.
• Always add fuel in a clean, well-ventilated outdoor area where there are no sparks or flames. Do
not smoke.
• 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 engine. Move the unit at least 30 feet (9.1 m) from the fueling
source and 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. Only
operate this unit in a well-ventilated outdoor area.
WHILE OPERATING
• Wear safety glasses or goggles that meet ANSI Z87.1 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.
• The cutting attachment shield must always be in place while operating the unit as a trimmer. Do not
operate unit without both trimming lines extended, and the proper line installed. Do not extend the
trimming line beyond the length of the shield.
• This unit has a clutch. The cutting attachment remains stationary when the engine is idling. If it does not,
have the unit adjusted by an authorized service technician.
• Adjust the handle to your size in order to provide the best grip.
• Be sure the cutting attachment is not in contact with anything before starting the unit.
• Use the unit only in daylight or good artificial light.
• Avoid accidental starting. Be in the starting position whenever pulling the starter rope. The operator and
unit must be in a stable position while starting. Refer to Starting/Stopping Instructions.
• Use the right tool. Only use this tool for its intended purpose.
• Do not overreach. Always keep proper footing and balance.
• Always hold the unit with both hands when operating. Keep a firm grip on both handles or grips.
• Keep hands, face, and feet at a distance from all moving parts. Do not touch or try to stop the cutting
attachment when it rotates.
• Do not touch the engine, gear housing or muffler. These parts get extremely hot from operation, even
after the unit is turned off.
• Do not operate the engine faster than the speed needed to cut, trim or edge. Do not run the engine at
high speed when not cutting.
• Always stop the engine when cutting is delayed or when walking from one cutting location to another.
• If you strike or become entangled with a foreign object, stop the engine immediately and check for
damage. Do not operate before repairing damage. Do not operate the unit with loose or damaged parts.
• Stop the unit, switch the engine to off, and disconnect the spark plug for maintenance or repair.
• Use only original equipment manufacturer replacement parts and accessories for this unit. These are
available from your authorized service dealer. Use of any unauthorized parts or accessories could lead to
serious injury to the user, or damage to the unit, and void your warranty.
• Keep unit clean of vegetation and other materials. They may become lodged between the cutting
attachment and shield.
• To reduce fire hazard, replace a faulty muffler and spark arrestor. Keep the engine and muffler free from
grass, leaves, excessive grease or carbon build up.
OTHER SAFETY WARNINGS
• Never store a fueled unit inside a building where fumes may reach an open flame or spark.
• Allow the engine to cool before storing or transporting. Be sure to secure the unit while transporting.
• IMPORTANT SAFETY INSTRUCTIONS •
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.
FOR QUESTIONS, CALL 1-877-282-8684 IN U.S. OR 1-800-668-1238 IN CANADA
SAFETY ALERT:
Indicates danger, warning or caution. Attention is required in order to
avoid serious personal injury. May be used in conjunction with other symbols or pictographs.
DANGER:
Failure to obey a safety warning will result in serious injury to yourself or to
others. Always follow the safety precautions to reduce the risk of fire, electric shock and
personal injury.
WARNING:
Failure to obey a safety warning can result in injury to yourself and others. Always
follow the safety precautions to reduce the risk of fire, electric shock and personal injury.
CAUTION:
Failure to obey a safety warning may result in property damage or personal injury
to yourself or to others. Always follow the safety precautions to reduce the risk of fire, electric
shock and personal injury.
WARNING:
When using the unit, you must follow the safety 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.
WARNING:
Gasoline is highly flammable, and its vapors can explode if ignited. Take the
following precautions:
CALIFORNIA PROPOSITION 65
WARNING:
Engine exhaust, some of its constituents and certain finished components
contain or emit chemicals known to the State of California to cause cancer and birth
defects or other reproductive harm. Wash hands after handling.