DeWalt DW33 Lawn Mower Manual

The DeWalt DW33 is a 21-inch self-propelled gas lawn mower featuring a 190cc Briggs & Stratton engine, 3-in-1 mulching/bagging/side-discharge capability, single-lever height adjustment (1.5-4 inches), 2.1 bushel rear bag, electric start with backup recoil, variable speed self-propulsion, and durable steel deck. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Assembly Instructions 3. First-Time Setup 4. Specifications 5. Controls and Operation 6. Cutting Height Adjustment 7. 3-in-1 Discharge System 8. Maintenance Schedule 9. Storage & Winterization 10. Safety Information 11. Troubleshooting

Features at a Glance

Key components: 21-inch steel cutting deck, 190cc Briggs & Stratton engine, rear collection bag, single-lever height adjuster, electric start key, self-propulsion drive control.

FeatureDescription
Engine190cc Briggs & Stratton 4-cycle OHV engine
Cutting Width21 inches
Cutting HeightSingle-lever adjustment (1.5" to 4")
Drive SystemVariable speed self-propulsion (front-wheel drive)
Starting SystemElectric start with backup recoil
Discharge OptionsMulch, Bag, Side-discharge (3-in-1)
Bag Capacity2.1 bushels (rear bag)
Deck MaterialPowder-coated steel
Wheels8-inch rear, 7-inch front
Fuel Tank1.1 quarts (unleaded gasoline only)

Assembly Instructions

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

  1. Attach handle: Insert lower handle into deck brackets, secure with provided bolts and wing nuts.
  2. Install upper handle: Connect to lower handle, tighten knobs.
  3. Attach grass bag: Hang bag frame on rear hooks, attach bag to frame.
  4. Install side-discharge chute (if needed): Snap into opening on right side of deck.
  5. Add oil and fuel: Fill engine with SAE 10W-30 oil (check dipstick). Add fresh unleaded gasoline.

WARNING! Do not add fuel indoors or near ignition sources. Ensure all bolts are tight before operation.

First-Time Setup

Before first use, complete assembly and perform pre-operation checks.

  1. Check oil level: Ensure oil is at full mark on dipstick.
  2. Add fuel: Use fresh unleaded gasoline (87 octane or higher). Do not overfill.
  3. Battery charge: For electric start, ensure battery is fully charged (if applicable).
  4. Adjust cutting height: Set lever to desired height (recommend 2.5-3 inches for first mow).
  5. Test start: In open area, follow starting procedure.

CAUTION! Always start mower outdoors. Keep hands and feet clear of moving parts.

Specifications

Controls and Operation

Handle Controls: Drive control lever, height adjustment lever, electric start key slot, recoil starter handle.

Starting Procedure:

  1. Electric start: Insert key, turn to ON. Pull drive control lever to handle. Press start button.
  2. Recoil start: Turn key to ON. Pull drive control lever to handle. Pull recoil cord briskly.

Operation: Squeeze drive control lever to engage self-propulsion; release to stop. Adjust speed with throttle control. To stop engine, turn key to OFF.

Cutting Height Adjustment

Single-lever adjustment for all four wheels simultaneously.

  1. Stop engine and wait for blade to stop.
  2. Pull height adjustment lever outward.
  3. Move lever to desired height setting (1.5 to 4 inches).
  4. Release lever to lock into position.

Tip: For healthier grass, never cut more than 1/3 of grass height at one time. Adjust height seasonally.

3-in-1 Discharge System

Configure for mulching, bagging, or side-discharge.

  1. Mulching: Install mulch plug (closes side discharge). Grass clippings are cut finely and returned to lawn.
  2. Bagging: Attach rear bag. Ensure side discharge is closed with mulch plug or chute cover.
  3. Side-Discharge: Install side-discharge chute. Remove mulch plug and rear bag.

WARNING! Always stop engine before changing discharge configuration. Ensure all parts are securely installed.

Maintenance Schedule

MaintenanceFrequency
Check oil levelBefore each use
Check air filterEvery 25 hours
Replace spark plugEvery 100 hours
Change oilFirst 5 hours, then every 50 hours
Sharpen/replace bladeEvery 25 hours or as needed
Clean under deckAfter each use (when cool)
Check tire pressureMonthly
Lubricate wheelsEvery season

Storage & Winterization

For long-term storage (over 30 days):

  1. Drain or stabilize fuel: Run engine until tank is empty, or add fuel stabilizer.
  2. Change oil: Replace with fresh oil.
  3. Remove spark plug: Add 1 teaspoon of oil into cylinder, pull recoil slowly to distribute, reinstall plug.
  4. Clean thoroughly: Remove grass clippings from deck, wheels, and engine.
  5. Store indoors: Keep in dry, covered location. Protect from moisture.

CAUTION! Never store mower with fuel in tank indoors or in enclosed spaces without proper stabilization.

Safety Information

Always: Read manual before operation. Wear eye protection and sturdy shoes. Clear mowing area of debris. Mow in daylight only. Keep children and pets away.

Never: Operate on slopes greater than 15 degrees. Mow wet grass. Remove safety devices or guards. Put hands or feet near moving parts. Allow children to operate.

Emergency stop: Release drive control lever and turn key to OFF immediately.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startNo fuel, bad spark plug, stale fuelCheck fuel level; replace spark plug; drain old fuel.
Poor cutting performanceDull blade, low engine speedSharpen or replace blade; check throttle setting.
Self-propulsion not workingDrive belt loose, control cableCheck drive belt tension; inspect control cable.
Excessive vibrationBent blade, loose partsStop engine immediately. Check blade balance and tightness.
Grass clumpingWet grass, cutting too lowMow when grass is dry; raise cutting height.
Electric start not workingDead battery, loose connectionCharge battery; check wiring connections.

Service: For repairs, contact authorized DeWalt service center. Do not attempt major repairs unless qualified.

Support: 1-800-433-9258; www.dewalt.com

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