Cub cadet ST2020 User Manual

Operator’s Manual

TABLE OF CONTENTS

Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Rules for Safe Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Know Your Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Assembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Oil and Fuel Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Starting/Stopping Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Maintenance and Repair Instructions . . . . . . . . . . . . . . . . . . . . . .10

Cleaning and Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Troubleshooting Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

2-Cycle Gasoline Trimmer

ST2020

SAVE THESE INSTRUCTIONS

769-06373 P00 (12/10)

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.

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.

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 0.095 inch (2.41 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 mix and 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 unit. 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. Operate this unit only 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 head 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 head remains stationary when the engine is idling. If it does not, have the unit adjusted by an authorized service technician.

• Adjust the D-handle to your size in order to provide the best grip.

• Be sure the cutting head is not in contact with anything before starting the unit.

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

RULES FOR SAFE OPERATION

• 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

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.

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.

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 #753-05169 Muffler Assembly.

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.

• 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 head 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 head 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.

• Store the unit in a dry area, locked up or up high to prevent unauthorized use or damage, 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 someone this unit, also loan them these instructions.

SAVE THESE INSTRUCTIONS

RULES FOR SAFE OPERATION

• 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.

• SAFETY ALERT SYMBOL

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

• HOT SURFACE WARNING

Do not touch a hot muffler or cylinder. You may get burned. These parts get extremely hot from operation. When turned off, they remain hot for a short time.

• 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.

• KEEP BYSTANDERS AWAY

WARNING: Keep all bystanders, especially children and

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

• THROWN OBJECTS AND ROTATING CUTTER CAN CAUSE SEVERE INJURY

WARNING: Small objects can be propelled at high speed,

causing injury. Keep away from the rotating rotor.

SYMBOL MEANING

• CHOKE CONTROL

1. • FULL choke position

2. • PARTIAL choke position

3. • RUN choke position

• UNLEADED FUEL

Always use clean, fresh unleaded fuel

• ON/OFF STOP CONTROL

ON / START / RUN

• ON/OFF STOP CONTROL

OFF or STOP

SYMBOL MEANING

•OIL

Refer to operator’s manual for the proper type of oil.

• DO NOT USE E85 FUEL IN THIS UNIT

WARNING: It has been proven that fuel containing

greater than 10% ethanol will likely damage this engine and void the warranty.

KNOW YOUR UNIT

Cutting Head Shield

Fuel Cap

Throttle Control

D-Handle

Cutting Head

Shaft Grip

Primer Bulb

Blue Choke Lever

Spark Plug

Engine Stand

On/Off Stop Control

Shaft Housing

Starter Rope Grip

Line Cutting Blade

Muffler

EZ-Link™

Air Filter/

Muffler Cover

APPLICATIONS

As a trimmer:

• Cutting grass and light weeds

• Edging

• Decorative trimming around trees, fences, etc. Other optional accessories may be used with this unit. Refer to Operating

the EZ-Link System for a list of add-ons.

NO TOOLS REQUIRED!

Shoulder Strap Clip

INSTALL AND ADJUST THE D-HANDLE

1. Push the D-handle down onto the shaft housing (Fig. 1). The squared bolt hole in the handle is to the right.

Shaft Grip

Shaft Housing

D-Handle

Tighten

Minimum 6 inches

(15.24 cm)

Bolt

2. Insert the shoulder bolt into the squared hole in the handle and push through. On the left side of the handle, place the washer on the bolt, then screw the wing nut onto the bolt. Do not tighten until you make the handle adjustment.

3. Rotate the D-handle to place the grip above the top of the shaft housing. Place it a minimum of 6 inches (15.24 cm) from the end of the shaft grip.

4. While holding the unit in the operating position (Fig. 2), position the Dhandle to the location that provides you the best grip.

5. Tighten the wing nut until the D-handle is secure.

Fig. 1

Fig. 2

INSTALL THE CUTTING HEAD SHIELD

Use the following instructions if the cutting head shield on your unit is not installed.

1. Place the cutting head shield onto the shaft housing. Be sure the guard mounting bracket slides into the slot on the edge of the cutting shield. Rotate the shield into place, counterclockwise. The holes in the guard mounting bracket and cutting head shield will line up (Fig. 3).

Shaft Housing

Cutting Head Shield

Guard

Mounting

Bracket

Fig. 3

ASSEMBLY INSTRUCTIONS

WARNING: Never operate the trimmer without the cutting

head shield in place to prevent serious personal injury.

Washer

Guard

Mounting

Bracket

Square Bolt

Wing Nut

Fig. 4

Hole

Square Bolt

Cutting Head Shield

Washer

Fig. 5

2. From inside the cutting head shield, push the square bolt through the hole until the threaded end protrudes through the guard mounting bracket (Fig. 4).

3. Put the washer on the bolt, then screw the wing nut onto the bolt and tighten. Figure 5 shows the installation process from underneath the unit.

Wing Nut

Washer

Wing Nut

Cutting Head and Shield: Underside View

For decorative trimming / edging with the line head cutting, lock the release button of the lower boom into the 90° hole (Fig. 8).

OPERATING THE EZ-LINK™ SYSTEM

The EZ-Link™ system enables the use of these optional Add-Ons:

Mach 4® Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .AF720

Articulating Hedge Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AH720*

Brushcutter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .BC720*

Bladed Pruner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .BP720

Blower Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .BT720*

Blower Vacuum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .BV720

Garden Cultivator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GC720

Lawn Dethatcher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .LD720

Lawn Edger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LE720*

Pole Saw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PS720

Straight Shaft Trimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SS725

Snow Thrower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ST720

Turbo Blower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TB720

* Do NOT use this add-on with an electric powered product.

Removing the Add-On

1. Turn the knob counterclockwise to loosen (Fig. 6).

2. Press and hold the release button (Fig. 6).

Fig. 6

EZ-Link™

Coupler

Release

Button

Guide Recess

Knob

Primary Hole

Upper Shaft Housing

EZ-Link™ Coupler

2. While firmly holding the add-on, push it straight into the EZ-Link™ coupler (Fig. 7).

NOTE: Aligning the release button with the guide recess will help

installation (Fig. 6).

3. Turn the knob clockwise to tighten (Fig. 8).

Fig. 7

Fig. 8

Knob

Lower Shaft Housing

Release Button

90˚ Edge

Trimming Hole

ASSEMBLY INSTRUCTIONS

3. While firmly holding the upper shaft housing, pull the add-on straight out of the EZ-Link™ coupler (Fig. 7).

Installing the Add-On NOTE: To make installing or removing the add-on easier, place the unit on

the ground or on a work bench.

1. Turn the knob counterclockwise to loosen (Fig. 6).

WARNING: When using any add-on, read and understand

that add-on’s specific manual before you begin operation. Follow all applicable safety information.

WARNING: To avoid serious personal injury and damage to

the unit, shut the unit off before removing or installing add-ons.

CAUTION: Lock the release button in the primary hole and

securely tighten the knob before operating this unit.

CAUTION: Add-ons are to be used in the primary hole only.

Using the wrong hole could lead to personal injury or damage to the unit.

OIL AND FUEL INFORMATION

OIL AND FUEL MIXING INSTRUCTIONS

Old and/or improperly mixed fuel are the main reasons for the unit not running properly. Be sure to use fresh, clean unleaded fuel. Follow the instructions carefully for the proper fuel/oil mixture.

Definition of Blended Fuels

Today's fuels are often a blend of gasoline and oxygenates such as ethanol, methanol, or MTBE (ether). Alcohol-blended fuel absorbs water. As little as 1% water in the fuel can make fuel and oil separate. It forms acids when stored. When using alcohol-blended fuel, use fresh fuel (less than 30 days old).

Using Blended Fuels

If you choose to use a blended fuel, or its use is unavoidable, follow recommended precautions:

• Always use the fresh fuel mix explained in your operator's manual

• Always agitate the fuel mix before fueling the unit

• Drain the tank and run the engine dry before storing the unit

Using Fuel Additives

The bottle of 2-cycle oil that came with this unit contains a fuel additive that will help inhibit corrosion and minimize the formation of gum deposits. Using the 2-cycle oil included with this unit is recommended. If unavailable, use a good 2-cycle oil designed for air-cooled engines along with a fuel additive, such as STA-BIL® Gas Stabilizer or an equivalent. Add 0.8 oz. (23 ml) of fuel additive per gallon of fuel according to the instructions on the container. NEVER add fuel additives directly to the unit's fuel tank.

Thoroughly mix the proper ratio of 2-cycle engine oil with unleaded gasoline in a separate fuel can. Use a 40:1 fuel/oil ratio. Do not mix them directly in the engine fuel tank. See the table below for specific gas and oil mixing ratios.

NOTE: One gallon (3.8 liters) of unleaded gasoline mixed with one 3.2 oz.

(95 ml) bottle of 2-cycle oil makes a 40:1 fuel/oil ratio.

NOTE: Dispose of the old fuel/oil mix in accordance with federal, state

and local regulations.

MIXING RATIO - 40:1

UNLEADED GAS* 2 CYCLE OIL

1 GALLON US

(3.8 LITERS)

3.2 FL. OZ. (95 ML)

1 LITER 25 ML

CAUTION: For proper engine operation and maximum

reliability, pay strict attention to the oil and fuel mixing instructions on the 2-cycle oil container. Using improperly mixed fuel can severely damage the engine.

*WARNING:

DO NOT USE E85 FUEL IN THIS UNIT. It

has been proven that fuel containing greater than 10% ethanol will likely damage this engine and void the warranty.

WARNING: Gasoline is extremely flammable. Ignited vapors

may explode. Always stop the engine and allow it to cool before filling the fuel tank. Do not smoke while filling the tank. Keep sparks and open flames at a distance from the area.

WARNING: Remove fuel cap slowly to avoid injury from fuel

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

WARNING: Add fuel in a clean, well ventilated outdoor area.

Wipe up any spilled fuel immediately. Avoid creating a source of ignition for spilt fuel. Do not start the engine until fuel vapors dissipate.

Fig. 9

Throttle Control

Fig. 11

Starting Position

On ( I )

Off (O)

Throttle Control

Fig. 10

Blue Choke Lever

Primer Bulb

STARTING INSTRUCTIONS

1. Mix fuel with oil. See Oil and Fuel Mixing Instructions.

2. Fill the fuel tank with fresh, clean fuel mix. Refer to Fueling the Unit. NOTE: There is no need to turn the unit on. The On/Off Stop Control is in

the ON ( I ) position at all times (Fig. 9).

3. Fully press and release the primer bulb 10 times, slowly. Some amount of fuel should be visible in the primer bulb and fuel lines (Fig. 10). If fuel can not be seen in the bulb, press and release the bulb until fuel is visible.

4. Place the blue choke lever in Position 1 (Fig. 10).

5. Crouch in the starting position (Fig. 11), squeeze the throttle control, and pull the starter rope out with a controlled and steady motion 5 times.

6. Place the blue choke lever in Position 2 (Fig. 10)

7. While squeezing the throttle control, pull the starter rope out with a controlled and steady motion 3-5 times.

8. Keep the throttle squeezed and allow the engine to warm up for 30 to 60 seconds.

9. Continue squeezing the throttle control, move the blue choke lever to Position 3 (Fig. 10) and continue warming the engine for an additional 60 seconds. The unit may be used during this time.

NOTE: Unit is properly warmed up when engine accelerates without hesitation. NOTE: The engine may take longer to warm up and reach maximum

operating speed at colder temperatures.

IF... the engine hesitates, return the blue choke lever to Position 2 (Fig. 10)

and continue warm-up.

IF... the engine does not start, go back to step 3. IF... the engine fails to start after a few attempts, place the blue choke

lever in Position 3 and squeeze the throttle control. Pull the starter rope out with a controlled and steady motion 3 to 8 times. The engine should start. If not, repeat.

IF WARM... If the engine is already warm, start the unit with the blue choke

lever in Position 2. After the unit starts, move the blue choke lever to Position 3.

STOPPING INSTRUCTIONS

1. Release the throttle control and allow the engine to cool down by idling.

2. Press and hold the On/Off Stop Control in the OFF (O) position until the unit comes to a complete stop (Fig. 9).

STARTING/STOPPING INSTRUCTIONS

WARNING:

Operate this unit only in a well-ventilated outdoor area. Carbon monoxide exhaust fumes can be lethal in a confined area.

WARNING: Avoid accidental starting. Make sure you are in

the starting position when pulling the starter rope (Fig. 11). To avoid serious injury, the operator and unit must be in a stable position while starting. Make sure that any Add-On item is installed correctly and secure before starting the unit.

OPERATING INSTRUCTIONS

Fig. 14

DECORATIVE TRIMMING

Decorative trimming is accomplished by removing all vegetation around trees, posts, fences and more. Rotate the whole unit so that the cutting head is at a 30° angle to the ground (Fig. 14).

Some line breakage will occur from:

• Entanglement with foreign matter

• Normal line fatigue

• Attempting to cut thick, stalky weeds

• Forcing the line into objects such as walls or fence posts

ADJUSTING TRIMMING LINE LENGTH

The Bump Head™ cutting head allows you to release trimming line without stopping the engine. To release more line, lightly tap the cutting head on the ground (Fig. 13) while operating the trimmer at high speed.

NOTE: Always keep the trimming line fully extended. Line release

becomes more difficult as the cutting line becomes shorter.

Fig. 13

Each time the head is bumped, about 1 inch (25.4 mm) of trimming line is released. A blade in the cutting head shield will cut the line to the proper length if any excess line is released. For best results, tap the Bump Head™ on bare ground or hard soil. If line release is attempted in tall grass, the engine may stall.

NOTE: Do not rest the Bump Head™ on the ground while the unit is running.

HOLDING THE TRIMMER

Before operating the unit, stand in the operating position (Fig. 12). Check for the following:

• The operator is wearing eye protection and proper clothing

• With a slightly-bent right arm, the operator’s right hand is holding the shaft grip

• The operator’s left arm is straight, with the left hand holding the D-handle

• The unit is at waist level

• The cutting head is parallel to the ground and easily contacts the grass without the need to bend over

Fig. 12

TIPS FOR BEST TRIMMING RESULTS

• For best trimming results, operate unit at full throttle.

• Keep the cutting head parallel to the ground.

• Do not force the cutting head. Allow the tip of the line to do the cutting, especially along walls. Cutting with more than the tip will reduce cutting efficiency and may overload the engine.

• Cut grass over 8 inches (200 mm) by working from top to bottom in small increments to avoid premature line wear or engine drag.

• Cut from right to left whenever possible. Cutting to the left improves the unit's cutting efficiency. Clippings are thrown away from the operator.

• Slowly move the trimmer into and out of the cutting area at the desired height. Move either in a forward-backward or side-to-side motion. Cutting shorter lengths produces the best results.

• Trim only when grass and weeds are dry.

• The life of your cutting line is dependent upon: — Proper adherence of trimming techniques (explained above) — What vegetation is cut — Where vegetation is cut

For example, the line will wear faster when trimming against a foundation wall as opposed to trimming around a tree.

WARNING: Always wear eye, hearing, foot and body

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

CAUTION:

Do not remove or alter the line cutting blade assembly. Excessive line length will make the clutch overheat. This may lead to serious personal injury or damage to the unit.

MAINTENANCE SCHEDULE

Perform these required maintenance procedures at the frequency stated in the table. These procedures should also be a part of any seasonal tune-up.

NOTE: Some maintenance procedures may require special tools or skills.

If you are unsure about these procedures take your unit to any non-road engine repair establishment, individual or authorized service dealer.

NOTE: Maintenance, replacement, or repair of the emission control

devices and system may be performed by any non-road engine repair establishment, individual or authorized service dealer.

NOTE: Please read the California/EPA statement that came with the unit for

a complete listing of terms and coverage for the emissions control devices, such as the spark arrestor, muffler, carburetor, etc.

FREQUENCY MAINTENANCE REQUIRED REFER TO

Before starting engine Fill fuel tank with fresh fuel* p. 7 Every 10 hours Clean and re-oil air filter p. 12

Every 25 hours Check spark plug condition and gap p. 13

Indexing Teeth

Fig. 16

Fig. 17

LINE INSTALLATION

This section covers both SplitLine™ and standard single line installation. Always use original equipment manufacturer 0.095 in. (2.41 mm) replacement line. Other types of line may make the engine overheat or fail.

There are two methods to replace the trimming line:

• Wind the inner reel with new line

• Install a prewound inner reel

Winding the Existing Inner Reel

1. Hold the outer spool with one hand and unscrew the bump knob counterclockwise (Fig. 15). Inspect the bolt inside the bump knob to make sure it moves freely. Replace the bump knob if damaged.

2. Remove the inner reel from the outer spool (Fig. 16).

3. Remove the spring from the inner reel (Fig. 16).

4. Use a clean cloth to clean the inner reel, spring, shaft and inner surface of the outer spool.

5. Check the indexing teeth on the inner reel and outer spool for wear (Fig. 17). If necessary, remove burrs or replace the reel and spool.

Bump Knob

Bolt

Fig. 15

MAINTENANCE AND REPAIR INSTRUCTIONS

WARNING:

To prevent serious injury, never perform maintenance or repairs with unit running. Always service and repair a cool unit. Disconnect the spark plug wire to ensure that the unit cannot start.

WARNING: Never use metal-reinforced line, wire, chain or

rope. These can break off and become dangerous projectiles.

NOTE: Always use the correct line length when installing trimming line on

the unit. The line may not release properly if the line is too long.

For Use with

Single Line ONLY

Fig. 18

NOTE: SplitLine™ can only be used with the inner reel with the slotted

holes. Single line can be used on either type of inner reel. Use Figure 18 to identify the inner reel you have.

Outer Spool

Spring

Inner Reel

For Use with SplitLine™

or Single Line

Slotted

Holes

Single Line Installation

Go To Step 8 for SplitLine™ Installation

6. Take approximately 18 feet (5.4 m) of new trimming line, loop it into two equal lengths. Insert each end of the line through one of the two holes in the inner reel (Fig. 19). Pull the line through the inner reel so that the loop is as small as possible.

7. Wind the lines in tight even layers, onto the reel (Fig. 20). Wind the line in the direction indicated on the inner reel. Place your index finger between the two lines to stop the lines from over-lapping. Do not overlap the ends of the line. Proceed to step 11.

SplitLine™ Installation

8. Take approximately 9 feet (3 m) of new trimming line. Insert one end of the line through one of the two holes in the inner reel (Fig. 21). Pull the line through the inner reel until only about 4 inches is left out.

9. Insert the end of the line into the open hole in the inner reel and pull the line tight to make the loop as small as possible (Fig. 21).

13. Insert the ends of the line through the eyelets in the outer spool and place inner reel with the spring inside the outer spool (Fig. 23). Push the inner reel and outer spool together. While holding the inner reel and outer spool, grasp the ends and pull firmly to release the line from the holding slots in the reel.

10. Before winding, split the line back about 6 inches.

11. Wind the line in tight even layers in the direction indicated on the inner reel. NOTE: Failure to wind the line in the direction indicated will cause the

cutting head to operate incorrectly.

12. Insert the ends of the line into the two holding slots (Fig. 22).

MAINTENANCE AND REPAIR INSTRUCTIONS

INSTALLING A PREWOUND REEL

1. Hold the outer spool with one hand and unscrew the bump knob clockwise (Fig. 15). Inspect the bolt inside the bump knob to make sure it moves freely. Replace the bump knob if damaged.

2. Remove the old inner reel from the outer spool (Fig. 16).

3. Remove the spring from the old inner reel (Fig. 16).

4. Place the spring in the new inner reel.

NOTE: The spring must be assembled on the inner reel before reassembling

the cutting head.

5. Insert the ends of the line through the eyelets in the outer spool (Fig. 23).

6. Place the new inner reel inside the outer spool. Push the inner reel and outer spool together. While holding the inner reel and outer spool, grasp the ends and pull firmly to release the line from the holding slots in the spool.

7. Hold the inner reel in place and install the bump knob by turning clockwise. Tighten securely.

NOTE: The spring must be assembled on the inner reel before reassembling

the cutting head.

14. Hold the inner reel in place and install the bump knob by turning counterclockwise. Tighten securely.

Fig. 19

Fig. 21

Fig. 22

Fig. 23

Loop

Spring

Holding Slots

Loop

Fig. 20

Cleaning the Air Filter

Failure to maintain your air filter properly can result in poor performance or can cause permanent damage to your engine.

1. Remove the air filter/muffler cover. Refer to Removing the Air Filter/ Muffler Cover.

2. Turn cover over and look inside to locate the air filter. Remove the air filter from inside the air filter/muffler cover (Fig. 25).

Fig. 25

Air Filter

Inside Muffler C over

MAINTENANCE AND REPAIR INSTRUCTIONS

3. Wash the filter in detergent and water. Rinse the filter thoroughly. Squeeze out excess water. Allow it to dry completely.

4. Apply enough clean SAE 30 oil to lightly coat the filter.

5. Squeeze the filter to spread and remove excess oil.

6. Replace the air filter inside the air filter/muffler cover (Fig. 25).

NOTE: Operating the unit without the air filter and air filter/muffler cover

assembly will VOID the warranty.

Reinstalling the Air Filter/Muffler Cover

1. Place the air filter/muffler cover over the back of the carburetor and muffler. Align the screw holes.

2. Insert the four (4) screws into the holes in the air filter/muffler cover (Fig. 24) and tighten.

Do not over tighten.

Fig. 24

Screws

Blue Choke Lever

AIR FILTER MAINTENANCE Removing the Air Filter/Muffler Cover

1. Place the blue choke lever in Position 2.

2. Remove the four (4) screws securing the air filter/muffler cover (Fig. 24). Use a flat blade or T20 Torx bit screwdriver.

3. Pull the cover from the engine. Do not force.

WARNING: To avoid serious personal injury, always turn

your unit off and allow it to cool before you clean or service it.

Fig. 26

Idle Speed Screw

IDLE SPEED ADJUSTMENT

The idle speed of the engine is adjustable through the air filter/muffler cover (Fig. 26).

NOTE: Careless adjustments can seriously damage your unit. An

authorized service dealer should make carburetor adjustments.

If, after checking the fuel mixture and cleaning the air filter, the engine still will not idle, adjust the idle speed screw as follows:

1. Start the engine and let it run at a high idle for a minute to warm up. Refer to Starting/Stopping Instructions.

2. Release the throttle trigger and let the engine idle. If the engine stops, insert a small Phillips or flat blade screwdriver into the hole in the air filter/muffler cover (Fig. 26). Turn the idle speed screw in, clockwise, 1/8 of a turn at a time (as needed) until the engine idles smoothly.

NOTE: The cutting head should not rotate when the engine idles.

3. If the cutting head rotates when the engine idles, turn the idle speed

screw counterclockwise 1/8 of a turn at a time (as needed), to reduce idle speed.

Checking the fuel mixture, cleaning the air filter, and adjusting the idle speed should solve most engine problems.

If not and all of the following are true:

• The engine will not idle

• The engine hesitates or stalls on acceleration

• There is a loss of engine power Have the carburetor adjusted by an authorized service dealer.

WARNING: The cutting head may spin during idle speed

adjustments. Wear protective clothing and observe all safety instructions to prevent serious personal injury.

WARNING: To prevent serious personal injury, make sure

the cutting head has stopped rotating before you turn it off and set it down.

MAINTENANCE AND REPAIR INSTRUCTIONS

CLEANING

Use a small brush to clean off the outside of the unit. Do not use strong detergents. Household cleaners that contain aromatic oils such as pine and lemon, and solvents such as kerosene, can damage plastic housing or handle. Wipe off any moisture with a soft cloth.

STORAGE

• Never store the unit with fuel in the tank where fumes may reach an open flame or spark.

• Allow the engine to cool before storing.

• Store the unit locked up 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

If the unit will be stored for an extended time, use the following storage procedure:

1. Drain all fuel from the fuel tank into a container with the same 2-cycle fuel

mixture. Do not use fuel that has been stored for more than 30 days. Dispose of the old fuel/oil mix in accordance with federal, state and local regulations.

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 high

quality motor oil into the cylinder. Pull the starter rope slowly to distribute the oil. Reinstall the spark plug.

NOTE: Remove the spark plug and drain all of the oil from the cylinder

before attempting to start the trimmer after storage.

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. The unit is ready for storage.

REPLACING THE SPARK PLUG

Use a #791-610311B spark plug, a Champion

ref. # RDJ7Y spark plug, or

equivalent. The correct air gap is 0.025 inch (0.635 mm).

1. Stop the engine and allow it to cool. Grasp the plug wire firmly and pull the boot from the spark plug.

2. Clean around the spark plug. Remove the spark plug from the cylinder head by turning a 5/8 in. socket counterclockwise.

3. Replace a cracked, fouled or dirty spark plug. Set the air gap at 0.025 in. (0.635 mm) using a feeler gauge (Fig. 27).

4. Install a correctly-gapped spark plug in the cylinder head. Tighten by turning the 5/8-inch socket clockwise until snug.

If using a torque wrench, torque to:

110-120 in.•lb. (12.3-13.5 N•m) Do not over tighten.

0.025 in.

(0.635 mm)

Fig. 27

WARNING:

Do not sand blast, scrape or clean electrodes.

Grit in the engine could damage the cylinder.

WARNING: To avoid serious personal injury, always turn

your unit off and allow it to cool before you clean or service it.

CLEANING AND STORAGE

CAUSE ACTION

TROUBLESHOOTING

If further assistance is required, contact your authorized service dealer.

Air filter is plugged Replace or clean the air filter

Old or improperly mixed fuel Drain fuel tank and add fresh fuel mixture

Improper idle speed Adjust according to the Idle Speed Adjustment section

Empty fuel tank Fill fuel tank with properly mixed fuel

Primer bulb wasn't pressed enough Press primer bulb fully and slowly 10 times

Engine is flooded Place blue choke lever in position 3, squeeze the trigger and pull the starter rope

Old or improperly mixed fuel Drain fuel tank and add fresh fuel mixture

Fouled spark plug Replace or clean the spark plug

Old or improperly mixed fuel Drain fuel tank and add fresh fuel mixture

Fouled spark plug Replace or clean the spark plug

Old or improperly mixed fuel Drain fuel tank and add fresh fuel mixture

Cutting head bound with grass Stop the engine and clean the cutting head

Dirty air filter Clean or replace the air filter

Cutting head bound with grass Stop the engine and clean the cutting head

Cutting head out of line Refill with new line

Inner reel bound up Replace the inner reel

Cutting head dirty Clean inner reel and outer spool

Line welded Disassemble, remove the welded section and rewind

Line twisted when refilled Disassemble and rewind the line

Not enough line is exposed Push the bump knob and pull out line until 4 inches (102 mm) of line is

outside of the cutting head

Oil, cleaner or lubricant in cutting head Clean and thoroughly dry the cutting head

ENGINE WILL NOT START

ENGINE WILL NOT IDLE

ENGINE WILL NOT ACCELERATE

ENGINE LACKS POWER OR STALLS WHEN CUTTING

CUTTING ATTACHMENT WILL NOT ADVANCE LINE

CUTTING LINE ADVANCES UNCONTROLLABLY

ENGINE*

* 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.

Engine Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air-Cooled, 2-Cycle

Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.25 in. (31.75 mm)

Displacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 cu in. (31 cc)

Clutch Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centrifugal

Idle Speed RPM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,600 - 3,600 rpm

Operating RPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6,500+ rpm

Ignition Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic

Ignition Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rocker Switch

Spark Plug Gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025 in. (0.635 mm)

Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel/Oil Mixture

Fuel/Oil Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40:1

Carburetor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diaphragm, All-Position

Starter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spring Assist Starting™ Auto Rewind

Muffler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baffled with Guard

Throttle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Spring Return

Fuel Tank Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 oz. (384 ml)

Drive Shaft Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steel Tube, EZ-Link™

Throttle Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Finger-Tip Trigger

Approximate Unit Weight (No fuel, with cutting head, shield, and D-handle) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 lbs. (6 kg)

Cutting Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bump Head™

Line Spool Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 inches (76.2 mm)

Trimming Line Diameter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.095 inches (2.41 mm)

Cutting Path Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 inches (43.18 cm)

SPECIFICATIONS

DRIVE SHAFT & CUTTING HEAD*

+ 33 hidden pages

Cub cadet ST2020 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual