DeWalt 11A-B9KL347 Lawn Mower Manual

The DeWalt 11A-B9KL347 is a powerful 11 Amp electric lawn mower designed for residential use. It features a 20-inch steel cutting deck, 2-in-1 mulching and bagging capability, a single-lever height adjustment for 7 cutting positions, a durable steel deck, a foldable handle for easy storage, and a safety key start system. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Assembly & Setup 3. First-Time Operation 4. Specifications 5. Controls and Settings 6. Cutting & Operation 7. Maintenance & Cleaning 8. Safety Features 9. Storage 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: 11 Amp electric motor, 20-inch steel cutting deck, 2-in-1 function (mulch/bag), single-lever height adjustment, foldable handle, rear grass bag, safety start key, and cord retention hook.

FeatureDescription
Motor11 Amp electric motor for powerful cutting performance
Cutting Deck20-inch steel deck for durability and wide cutting path
Cutting System2-in-1 capability: Mulch or rear bag collection
Height AdjustmentSingle-lever adjusts all four wheels to 7 positions (1.25-3.75 inches)
HandleFoldable design for compact storage
Grass BagRear-mounted, easy-empty bag with fill indicator
Safety KeyRemovable safety key prevents accidental start-up
Cord HookIntegrated hook for managing power cord during use
Wheels8-inch rear and 7-inch front wheels for easy maneuverability
Start SystemPush-button start with safety key

Assembly & Setup

Unpack and inspect all parts. Assemble on a flat, stable surface.

  1. Attach the lower handle: Secure to deck using provided bolts and wrench.
  2. Attach the upper handle: Connect to lower handle, tighten knobs.
  3. Install the grass bag: Slide bag frame onto rear deck hooks.
  4. Install the mulch plug (if mulching): Insert into rear discharge chute.
  5. Attach the wheels: Slide onto axles and secure with push pins.
  6. Adjust cutting height: Set lever to desired position.

WARNING! Ensure mower is unplugged during assembly. Use proper tools and tighten all fasteners securely.

First-Time Operation

Before first use, inspect area for debris. Ensure proper electrical outlet and extension cord.

  1. Insert safety key into slot near handle.
  2. Plug mower into a grounded 120V outlet. Use a heavy-duty outdoor extension cord (min. 14 AWG).
  3. Adjust cutting height to highest setting for first mow.
  4. Select mulch or bag mode: Install mulch plug or grass bag accordingly.
  5. Press and hold safety handle, then press start button to begin mowing.

CAUTION! Always mow in dry conditions. Keep cord clear of cutting path. Do not mow on steep slopes.

Specifications

Controls and Settings

Main controls located on handle. Safety handle must be engaged to start motor.

Handle Controls: Safety handle/bar, Start button, Height adjustment lever, Cord hook.

Settings: Height adjustment (1-7), Mulch/Bag mode selection via plug or bag attachment. Safety: Removable safety key, push-button start only works when safety handle is held. Storage: Handle folds down by loosening knobs and pivoting.

Cutting & Operation

For optimal results, mow when grass is dry. Overlap passes slightly.

  1. Clear lawn of sticks, stones, and debris.
  2. Set cutting height based on grass type (higher for most grasses).
  3. Choose mulch mode for nutrient recycling or bag mode for clean collection.
  4. Start mower: Hold safety handle, press start button.
  5. Mow in straight, overlapping passes. Change direction periodically.
  6. Empty bag when full indicator shows; do not overfill.
  7. After mowing, release safety handle to stop blade. Unplug mower.

Tip: Sharpen blade annually for clean cuts. Avoid cutting wet grass to prevent clumping.

Maintenance & Cleaning

Regular maintenance ensures longevity and performance.

  1. After each use: Unplug mower. Clean underside of deck with brush or hose (after unplugging).
  2. Blade care: Periodically inspect blade for damage or dullness. Sharpen or replace as needed.
  3. Check fasteners: Tighten any loose bolts or knobs.
  4. Wheel inspection: Ensure wheels rotate freely.
  5. Store in a dry place.

WARNING! Always disconnect power before any maintenance. Wear gloves when handling blade.

Safety Features

Safety key: Must be inserted to operate. Safety handle: Blade stops within 3 seconds of release. Cord retention hook: Keeps cord away from cutting path. Discharge chute guard: Prevents direct access to blade.

Storage

Store mower in a clean, dry area. Fold handle to reduce space.

  1. Unplug and clean mower thoroughly.
  2. Empty and clean grass bag.
  3. Fold handle: Loosen knobs, pivot handle down, retighten lightly.
  4. Store mower on a level surface, away from moisture and extreme temperatures.

CAUTION! Do not store with fuel (not applicable). Keep out of reach of children.

Regulatory Information

This product complies with applicable U.S. safety standards. Contains no user-serviceable parts inside motor housing. Copyright © DeWalt. 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, outlet dead, cord issueInsert safety key, check outlet/GFCI, inspect cord for damage, ensure safety handle is engaged.
Poor cutting performanceDull blade, wet grass, low cutting heightSharpen or replace blade, mow when grass is dry, raise cutting height.
Mower vibrates excessivelyLoose blade or debris, unbalanced bladeUnplug, check and tighten blade bolt, remove debris, balance or replace blade.
Grass not discharging properlyWet grass, clogged deck, full bagMow dry grass, clean underside of deck, empty bag.
Motor stops during useOverload, thermal protection, cord disconnectLet motor cool, reduce cutting height/speed, check cord connection.

Reset: If motor overheats, unplug and wait 15 minutes to cool.

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

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