DeWalt DCMWSP255 Lawn Mower Manual

The DeWalt DCMWSP255 is a 20-inch cordless electric lawn mower powered by two 20V MAX* or 60V MAX FLEXVOLT* batteries (sold separately). It features a brushless motor for extended runtime, a 3-in-1 mulching, bagging, and side-discharge system, a single-lever height adjustment (1.5" to 4"), a folding handle for storage, and a push-button start. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Assembly & Setup 3. Operation Instructions 4. Specifications 5. Controls and Adjustments 6. Battery & Charging 7. Cutting & Discharge Options 8. Safety Features 10. Care & Maintenance 11. Regulatory Information 12. Troubleshooting

Features at a Glance

Key components: Deck with brushless motor, folding handle, battery ports, height adjustment lever, rear bag, mulch plug, safety key.

FeatureDescription
Power SourceDual 20V MAX* or 60V MAX FLEXVOLT* Batteries (Sold Separately)
Cutting Width20 inches
Cutting HeightSingle-lever adjustment, 6 positions (1.5" to 4")
Cutting Options3-in-1 (Mulch, Bag, Side Discharge)
Motor TypeBrushless
Start TypePush-Button Electric Start
HandleFolding for compact storage
Safety KeyRemovable key to prevent accidental start
Battery GaugeLED indicators on handle
Wheels8-inch rear, 7-inch front

Assembly & Setup

Unpack all parts and inspect for damage. Assembly requires basic tools (included).

  1. Attach the Lower Handle: Secure to deck using provided bolts and wrench.
  2. Attach the Upper Handle: Connect to lower handle, secure knobs.
  3. Install the Grass Bag: Attach bag frame to rear deck hooks.
  4. Install Batteries: Insert two fully charged 20V/60V batteries into ports on handle.
  5. Adjust Cutting Height: Set lever to desired position before starting.

WARNING! Ensure mower is off and batteries are removed during assembly. Keep hands clear of blade area.

Operation Instructions

Before first use, read all safety instructions. Ensure area is clear of debris.

  1. Insert Safety Key: Push fully into slot on control panel.
  2. Insert Batteries: Ensure they are fully charged and clicked into place.
  3. Adjust Height: Use single lever to set cutting height.
  4. Select Discharge Mode: Install mulch plug, bag, or open side chute.
  5. Start Mower: Hold safety bail handle against handle, then press start button.
  6. To Stop: Release bail handle; motor and blade will stop within 3 seconds.

CAUTION! Always wear eye and hearing protection. Do not mow wet grass.

Specifications

Controls and Adjustments

Handle Controls: Safety bail handle, Start/Stop button, Battery gauge LEDs. Deck Controls: Single-lever height adjustment, Discharge chute selector.

Adjustments: Cutting Height: Move lever to one of 6 positions. Handle Height: Optional adjustment holes (not on all models). Bag Indicator: Visual window shows when bag is full.

Battery Gauge: 3 LEDs indicate charge level (Green=High, Yellow=Medium, Red=Low/Charge).

Battery & Charging

Use only DeWalt 20V MAX* or 60V MAX FLEXVOLT* batteries and charger.

  1. Charging: Remove battery, insert into compatible charger. LED indicates status.
  2. Runtime: Varies based on grass condition, height, and battery capacity.
  3. Storage: Store batteries in cool, dry place away from metal objects.

Tip: For best performance, use two batteries of the same type and charge level.

Cutting & Discharge Options

Supports three cutting modes for versatility.

  1. Mulching: Install mulch plug. Cuts clippings finely and returns them to lawn.
  2. Bagging: Attach rear bag. Collects clippings for disposal.
  3. Side Discharge: Remove mulch plug and bag. Discharges clippings to the side (use with optional side discharge chute accessory).

WARNING! Always stop mower and remove safety key before changing discharge mode. Keep hands and feet away from discharge opening.

Safety Features

Safety Bail Handle: Blade stops within 3 seconds of release. Removable Safety Key: Prevents unauthorized or accidental starting. Blade Brake System: Meets ANSI safety standards.

Care & Maintenance

Disconnect batteries and remove safety key before any maintenance.

After Each Use: Clean underside of deck with brush or hose (ensure mower is off and unpowered). Wipe exterior with dry cloth. Check blade for damage or dullness.

Seasonal: Sharpen or replace blade as needed. Lubricate wheel axles if necessary. Store in a clean, dry place.

CAUTION! Never use water or cleaners on electrical components, battery ports, or controls.

Regulatory Information

This product complies with applicable ANSI/OPEI standards and U.S. CPSC regulations. Copyright © 2023 DeWalt. DeWalt, the yellow and black color scheme, and FLEXVOLT are trademarks of Stanley Black & Decker, Inc., used under license. For support, visit www.dewalt.com or contact 1-800-4-DeWalt (1-800-433-9258).

Troubleshooting

SymptomPossible CauseCorrective Action
Mower won't startSafety key not inserted, dead batteries, bail not engagedInsert safety key, charge/replace batteries, fully engage bail handle.
Poor cutting performanceDull blade, low battery, cutting height too lowSharpen/replace blade, charge batteries, raise cutting height.
Mower stops during useBatteries depleted, overload (grass too thick/wet)Charge batteries, mow in slower passes, ensure grass is dry.
Uneven cutDeck clogged, uneven tire pressure, worn bladeClean deck, check tire pressure (if applicable), inspect/replace blade.
Bag not fillingClogged chute, wet grass, mulch plug installedStop mower, clear chute, ensure grass is dry, remove mulch plug for bagging.

Reset: Remove batteries and safety key for 1 minute to reset electronics.

Service: 1-800-4-DeWalt; www.dewalt.com

DeWalt DCMWSP255 Lawn Mower Manual © - All Rights Reserved 2025