BLACK+DECKER GH900 String Trimmer/Edger

Introduction and Intended Use

This manual provides instructions for the BLACK+DECKER GH900 String Trimmer/Edger, designed for household trimming and edging applications.

⚠️ WARNING: Read all safety warnings and instructions before use. Failure to follow may result in electric shock, fire, or serious injury.

Intended Use: This string trimmer is designed for household trimming and edging applications.

DO NOT use under wet conditions or in the presence of flammable liquids or gases.

DO NOT allow children to contact the tool. Supervision is required for inexperienced operators.

Safety Alert Symbols and Words

This manual uses the following symbols and words to alert you to hazardous situations and risks:

• DANGER: Imminent hazard; will result in death or serious injury if not avoided.
• WARNING: Potentially hazardous situation; could result in death or serious injury if not avoided.
• CAUTION: Potentially hazardous situation; may result in minor or moderate injury if not avoided.
• (Used without word): Safety-related message.
• NOTICE: Practice not related to personal injury, but may result in property damage if not avoided.

General Power Tool Safety Warnings

WARNING: Read all safety warnings, instructions, illustrations, and specifications. Failure to follow may result in electric shock, fire, or serious injury.

Keep all warnings and instructions for future reference.

1) Work Area Safety

• Keep the work area clean and well-lit.
• Do not operate in explosive atmospheres (flammable liquids, gases, dust). Sparks may ignite fumes.
• Keep children and bystanders away. Distractions can cause loss of control.

2) Electrical Safety

• Power tool plugs must match the outlet. Never modify plugs. Use ungrounded plugs with earthed tools only.
• Avoid contact with earthed surfaces (pipes, radiators, etc.).
• Do not expose tools to rain or wet conditions.
• Do not abuse the cord. Keep cords away from heat, oil, sharp edges, and moving parts.
• Use outdoor-rated extension cords for outdoor use.
• Use a GFCI-protected supply in damp locations.

3) Personal Safety

• Stay alert, use common sense. Do not use when tired, ill, or under the influence of drugs/alcohol/medication.
• Use personal protective equipment (eye protection, dust mask, safety shoes, hard hat, hearing protection).
• Prevent unintentional starting: Ensure the switch is OFF before connecting to power, picking up, or carrying the tool.
• Remove adjusting keys or wrenches before starting.
• Do not overreach. Maintain proper footing and balance.
• Dress properly. Avoid loose clothing, jewelry, and long hair that can get caught in moving parts.
• Connect and use dust extraction facilities properly if provided.
• Do not let familiarity lead to complacency. Careless actions can cause severe injury.

Power Tool Use and Care

• Do not force the tool; use the correct tool for the application.
• Do not use if the switch is defective.
• Disconnect from power source before making adjustments, changing accessories, or storing.
• Store idle tools out of reach of children and untrained users.
• Maintain tools and accessories. Check for misalignment, binding, or broken parts. Repair damaged tools before use.
• Keep cutting tools sharp and clean.
• Use the tool and accessories according to instructions and working conditions.
• Keep handles and grasping surfaces dry, clean, and free from oil and grease.

Service

Have your power tool serviced by a qualified repair person using only identical replacement parts.

Important Safety Warnings

WARNING: Basic safety precautions should always be followed to reduce risk of fire, electric shock, and personal injury.

WARNING: Do not remove the guard. The guard must be attached during use. Operating without it voids the warranty.

CAUTION: When replacing line, use only 0.080" (2 mm) diameter twisted nylon monofilament line. Other diameters may degrade performance or cause damage.

• READ ALL INSTRUCTIONS
• ALWAYS WEAR EYE PROTECTION – Safety spectacles or goggles at all times.
• GUARD – Do not use without the guard attached.
• DRESS PROPERLY – Avoid loose clothing, jewelry, and long hair. Wear gloves and rubber-soled footwear. Do not operate barefoot or in open sandals. Wear long pants and protective hair covering.
• NYLON LINE – Keep face, hands, and feet clear of the rotating line.
• ROTATING LINE FUNCTION – Use care when trimming around screens and plants.
• DO NOT USE non-recommended materials (metal wire, rope).
• KEEP ALL BYSTANDERS AWAY – at a safe distance, especially children. Ensure others and pets are at least 100 feet (30 m) away.
• TO REDUCE REBOUND INJURY – work away from solid objects (walls, steps, trees). Be careful near solid objects and trim by hand if necessary.
• AVOID ACCIDENTAL STARTING – Do not carry the trimmer with a finger on the trigger.
• USE THE RIGHT APPLIANCE – Use only for its intended purpose.
• DON'T OVERREACH – Maintain proper footing and balance.
• DON'T FORCE APPLIANCE – Use the correct speed for better results and less injury risk.
• DAMAGE TO UNIT – If you strike or become entangled with a foreign object, stop immediately, unplug, check for damage, and repair before further use. Do not operate with a broken hub or spool.
• DAMAGE TO CORD – Keep cord away from rotating line. Unplug if damaged and replace before further use.
• SECURE EXTENSION CORD using the cord retainer.
• DISCONNECT TRIMMER when not in use, replacing line, or cleaning.
• AVOID DANGEROUS ENVIRONMENTAL CONDITIONS – Do not use in damp/wet locations or in rain.
• DO NOT OPERATE in gaseous or explosive atmospheres.
• STORE IDLE APPLIANCES INDOORS – in a dry, locked-up place away from children.
• STAY ALERT – Do not operate when tired, ill, or under the influence of alcohol, drugs, or medication.
• MAINTAIN APPLIANCES WITH CARE – Keep handles dry, clean, and free from oil/grease.
• GROUND FAULT CIRCUIT INTERRUPTER (GFCI) protection should be provided.
• CHECK DAMAGED PARTS – Inspect guards or other damaged parts for proper operation. Repair or replace as needed.
• DO NOT immerse appliance in water or squirt with a hose.
• DO NOT allow liquid inside.
• DO NOT store near fertilizers or chemicals.
• DO NOT clean with a pressure washer.
• Keep guards in place and working.
• Keep hands and feet away from cutting area.
• INSPECT THE AREA before use. Remove debris like rocks, glass, wire that can ricochet or cause injury.
• DO NOT leave appliance plugged in. Unplug when not in use and before servicing.
• DO NOT use with damaged cord or plug. Return to service center if damaged, dropped, left outdoors, or dropped in water.
• DO NOT pull or carry by cord. Keep cord away from heated surfaces.
• DO NOT unplug by pulling cord. Grasp the plug.
• DO NOT handle plug or appliance with wet hands.
• Turn off all controls before unplugging.
• Appliance is double-insulated. Use identical replacement parts.
• Use outdoor-rated extension cords (SJW or SJTW).
• Ensure extension cord is in good condition and correctly sized. Refer to the Minimum Gauge for Cord Sets chart. Use the next heavier gauge if in doubt.
• Maintain appliance with care – inspect extension cords periodically.
• To reduce risk of disconnection, secure extension cord to appliance plug (knot, strap, or connector).
• WARNING: Ensure a secure electrical connection between the appliance plug and extension cord. Check periodically. A loose connection can cause overheating, fire, and burning.
• WARNING: Do not use if the switch trigger does not operate correctly.

Component Identification (Fig. A)

The string trimmer/edger has the following components:

• 1. On/Off trigger switch
• 2. Cord retainer
• 3. Power cord plug
• 4. Main handle
• 5. Auxiliary handle
• 6. Main housing
• 7. Collar
• 8. Lower pole
• 9. Motor housing
• 10. Edge guide wheel
• 11. Guard
• 12. Spool housing

Assembly and Adjustments

WARNING: Turn unit OFF and disconnect from power source before making any adjustments or removing/installing parts. Accidental startup can cause injury.

Attaching the Auxiliary Handle (Fig. B-D)

For some models, the auxiliary handle (5) may need to be attached.

1. Press the auxiliary handle adjustment buttons (13) on both sides of the upper housing.
2. Position the auxiliary handle as shown in diagrams B-D. Push it partially on so the buttons are held when released.
3. Push the auxiliary handle completely onto the housing until it "snaps" into place.
4. NOTE: To adjust the handle up or down, press the buttons and move the handle.
5. NOTE: Adjust the handle so your front arm is straight when the edger is in the working position.

Installing the Guard (Fig. E, F)

WARNING: Never operate without the guard firmly attached. Damage or injury could result.

1. Remove the guard screw (15).
2. Slide the guard (11) fully onto the motor housing (9). Ensure tabs (18) on the guard engage ribs (14) on the trimmer head.
3. Continue sliding until the guard "snaps" into place. The locking tab (17) should snap into the housing slot (16).
4. Using a screwdriver, insert and tighten the guard screw (15).
5. After installation, remove the covering from the line cut-off blade on the guard's edge.

Height Adjustment (Fig. A, G)

CAUTION: Adjust trimmer length for proper working positions.

1. Loosen the height-adjust collar (7) by rotating it in the direction of the arrow shown in Figure A, G.
2. Move the upper housing up or down. Tighten the collar by rotating it opposite the direction shown in Figure A, G when the desired height is achieved.

Attaching Extension Cord (Fig. H)

An extension cord retainer (2) is built into the main handle to prevent the cord from unplugging.

• To use, double the extension cord about 8" (203 mm) from the end and insert into slot (18) in the handle area (Fig. H).
• Hook the loop over the extension cord retainer (2). Tug gently to ensure it's retained.
• Plug the receptacle end of the extension cord into the power cord plug (3) in the main handle.

Releasing the Cutting Line (Fig. A)

During transit, the cutting line is taped to the spool housing (12). Remove the tape.

Operation

WARNING: Turn unit OFF and disconnect from power source before making adjustments, changing accessories, replacing line, or cleaning. Accidental startup can cause injury.

WARNING: Always wear ANSI Z87.1 compliant eye protection.

CAUTION: Use only the appropriate type of cutting line.

CAUTION: Inspect the area to be trimmed. Remove wire, cord, or string-like objects that could entangle the line or spool. Be careful of wires bent outwards, like fence barbs.

Proper Hand Position (Fig. A, I)

WARNING: Always use proper hand position as shown. Always hold securely to anticipate sudden reactions.

Proper hand position requires one hand on the main handle (4) and one on the auxiliary handle (5).

Switching Trimmer On and Off (Fig. A)

WARNING: Never lock the trigger in the ON position.

1. To turn ON, squeeze the trigger (1).
2. To turn OFF, release the trigger.

Trimming (Fig. K, L)

1. With the trimmer ON, angle it and swing side to side (Fig. K).
2. Maintain a cutting angle of 5° to 10°. Do not exceed 10°.
3. Cut with the tip of the line.
4. Maintain a minimum distance of 24" (610 mm) between the guard and your feet (Fig. L).

Convert to Edging Mode (Fig. A, K, L)

WARNING: Disconnect the plug from the power source before making adjustments.

The trimmer can be used in trimming or edging mode.

1. To operate in edge mode, loosen the collar (7) by twisting counterclockwise.
2. Rotate the motor housing (9) 180° counterclockwise until it snaps into the edge position.
3. Twist the collar (7) clockwise until tight to secure it.
4. To return to trimming position, loosen the collar, rotate the motor housing (9) 180° clockwise, and tighten the collar (5).

NOTE: Line wear will be faster if positioned directly over sidewalks or abrasive surfaces.

Edging Mode Operation (Fig. A, L)

WARNING: When edging, stones, metal, and other objects can be thrown at high speed. The trimmer and guard are designed to reduce danger. Work away from solid objects to reduce rebound injury.

• Ensure other persons and pets are at least 100' (30 m) away.
• For best results, edge on borders deeper than 2" (50 mm).
• Do not use to create trenches.
• Use the edge guide (10) to guide the trimmer.
• Position the edge guide on the sidewalk or abrasive surface so the cutting line is over the grass or dirt area to be edged.
• Slightly tilt the trimmer for a closer cut.

Helpful Cutting Tips (Fig. A, I, J)

• Use the tip of the string for cutting; do not force the head into uncut grass.
• Use the edge guide along fences, houses, and flower beds.
• Wire and picket fences, stone/brick walls, curbs, and wood can cause rapid string wear or breakage.
• Do not let the spool cap (19) drag on the ground or other surfaces.
• For long growth, cut from the top down, not exceeding 13" (330 mm) high.
• Keep the trimmer tilted toward the cutting area.
• The trimmer cuts best when passing from left to right, avoiding debris thrown at the operator.
• Avoid trees and shrubs, as bark, moldings, siding, and fence posts can be damaged by the string.

Cutting Line / Line Feeding

Uses .065" (1.65 mm) diameter round nylon line. Line tips fray and wear. Cutting line wears faster and requires more feeding on abrasive surfaces or with heavy weeds.

Clearing Jams and Tangled Line (Fig. N)

WARNING: Disconnect from power source before assembly, adjustments, or accessory changes. Accidental startup can cause injury.

Line feeding hub may clog with sap or debris, causing jams, especially with thick weeds. Follow steps below to clear.

CAUTION: To avoid damage, trim line if it protrudes beyond the blade.

1. Disconnect the power source plug.
2. Press release tabs (20) on spool cap (19) and remove from spool housing (12).
3. Pull out the spool, clear any broken line or debris.
4. Fit the spool as described in "Replacing Spool Assembly".

Replacing Spool Assembly (Fig. M-P)

WARNING: Use of non-recommended accessories may be hazardous.

WARNING: Do not use blades or accessories not recommended by BLACK+DECKER. Serious injury or product damage may result.

Reload nylon line (bulk or prewound spool) as shown.

USE ONLY .065" (1.65 mm) DIAMETER ROUND NYLON MONOFILAMENT LINE. Do not use serrated or heavier gauge line, as it will overload the motor and cause overheating. This line is available from your local dealer or authorized service center.

1. Disconnect the power source plug.
2. Press release tabs (20) on spool cap (19) and remove from spool housing (12).
3. For best results, replace spool with BLACK+DECKER Model AF-100.
4. If lever (22) becomes dislodged, replace it correctly before inserting a new spool.
5. Remove dirt and grass from spool cap and housing.
6. Unfasten the end of the cutting line (25) and guide it into the eyelet (29).
7. Take the new spool (27) and push it onto the boss (23) in the housing. Rotate slightly until seated.
8. The line should protrude approximately 5-3/8" (136 mm) from the housing.
9. Align spool cap tabs with spool housing slots (28).
10. Snap spool cap (19) back on by depressing tabs (20) and pressing until it snaps securely.
11. NOTE: Ensure the cover is fully positioned. Listen for two audible clicks to confirm tabs are correctly located. Turn on the appliance. The nylon line will be cut automatically to the proper length within seconds.

NOTE: Other replacement parts (guards, spool caps) are available through authorized service centers. Call 1-800-544-6986 or visit www.blackanddecker.com.

Rewinding Spool from Bulk Line (Fig. Q-S)

Use Only .065" (1.65 mm) Round Diameter Line

Bulk line is available from local retailers. Hand-wound spools may tangle more frequently than factory-wound spools.

1. Disconnect the power source plug.
2. Remove the empty spool as described in "Replacing Spool Assembly".
3. Remove any remaining cutting line from the spool.
4. Fold the end of the cutting line (25) about 3/4" (19 mm). Feed the line into an anchoring slot (28).
5. Insert the 3/4" (19 mm) end of the bulk line into hole (29) adjacent to the slot. Ensure the line is tight against the spool.
6. Wind the line onto the spool in the direction of the arrow. Wind neatly in layers; do not crisscross.
7. When the wound line reaches the recesses (30), cut the line.
8. Fit the spool as described in "Replacing Spool Assembly".

Maintenance

WARNING: Turn unit OFF and disconnect from power source before any adjustments, accessory changes, line replacement, or cleaning. Accidental startup can cause injury.

Your BLACK+DECKER tool is designed for long operation with minimum maintenance. Proper care and regular cleaning ensure satisfactory performance.

Cleaning

WARNING: Blow dirt and dust from air vents with clean, dry air at least weekly. Wear ANSI Z87.1 eye protection.

WARNING: Never use solvents or harsh chemicals on non-metallic parts. Use a cloth dampened with mild soap and water only. Never let liquid enter the tool or immerse any part in liquid.

Accessories

WARNING: Use of accessories not offered by BLACK+DECKER may be hazardous. Use only BLACK+DECKER recommended accessories.

Recommended accessories are available from your local dealer or service center. Contact BLACK+DECKER at 1-800-544-6986 for assistance.

Replacing Guard (Fig. E, F)

WARNING: Never operate without the guard firmly in place. Damage or injury could result.

Remove Current Guard

1. Remove guard screw (15) (Fig. F).
2. Slide guard (11) off.

Assembling New Guard

1. Slide guard into place (Fig. E).
2. Replace and securely tighten guard screw (15).

Repairs

WARNING: For safety and reliability, repairs, maintenance, and adjustments should be performed by a BLACK+DECKER factory service center or authorized service center using identical replacement parts.

Register Online

Thank you for your purchase. Register your product for:

• WARRANTY SERVICE: Efficient service if a problem occurs.
• CONFIRMATION OF OWNERSHIP: Proof of purchase for insurance claims (fire, flood, theft).
• FOR YOUR SAFETY: Allows contact in case of a safety notification.

Register online at www.BlackandDecker.com/NewOwner.

Two-Year Limited Warranty

Black & Decker (U.S.) Inc. warrants this product to be free from defects in material or workmanship for two (2) years from the date of purchase, provided it is used in a home environment. This warranty does not cover failures due to abuse, accidental damage, or unauthorized repairs. Defective products meeting warranty conditions will be replaced or repaired at no charge.

For warranty service, return the product to the retailer or send it (prepaid) to a BLACK+DECKER authorized service center. Proof of purchase may be required. BLACK+DECKER service centers are listed online at www.blackanddecker.com. This warranty does not apply to accessories. This warranty gives you specific legal rights, and you may have other rights that vary by state or province.

For questions, contact your nearest BLACK+DECKER Service Center manager. This product is not intended for commercial use, which will void the warranty.

LATIN AMERICA: Warranty information for Latin America may differ. Check packaging or contact the local company/website.

Imported by: Black & Decker (U.S.) Inc., 701 E. Joppa Rd., Towson, MD 21286

www.blackanddecker.com (1-800-544-6986)