DeWalt 2x20V Max 21″ Self-Propelled Mower

Safety

The DCMW220 uses two 20V Max battery packs to run a steel-deck mower at 40V total system power. Remove both packs before cleaning, blade service, transport, or storage. Because the mower is self-propelled and weighs 78 lb without batteries, control footing before engaging drive. Wear eye protection, sturdy shoes, and long pants. Keep the discharge area pointed away from people, glass, vehicles, and open doors.

• Cutting width: 21".
• Deck material: steel.
• Height range: 1.5"-4".
• Bag capacity: 2.0 bushel.
• Do not bypass the bail, key, or drive controls.

Mow only in clear daylight or strong work lighting. Avoid wet slopes, loose gravel, and hidden wire. Stop the blade before crossing paths, sidewalks, or bare ground.

Unboxing & first run

Remove the mower from the carton with two hands on solid frame points, not on the bail cable. Confirm the bag, mulch plug, discharge hardware, charger paperwork, and blade documentation are present. Raise the handle, lock both sides evenly, and inspect the underside before batteries are installed. The steel deck can hold packaging scraps near the blade after shipping.

• Model reference: DCMW220.
• Power: 2x20V Max, 40V total.
• Cutting width: 21".
• Bag capacity: 2.0 bushel.
• Weight without battery: 78 lb.

For the first run, use a mid-to-high height setting on dry grass. Start the blade, then engage self-propel gently and confirm the mower tracks straight. Stop after a short pass to check bag seating, wheel height, and unusual vibration.

Controls layout

The operator handle groups the safety key, start button, blade bail, and self-propel drive bar or lever. Release the blade bail to stop cutting; release the drive control to stop wheel assist. The height adjuster sets the steel deck between 1.5"-4", and the rear door accepts the bag or mulch plug. Battery compartments sit under the top cover and must close securely before mowing.

• Start sequence: insert key, press start, pull blade bail.
• Drive: engage self-propel only after the blade area is clear.
• Speed control: set slower for turns, slopes, and thick grass.
• Height lever: adjust with blade stopped.
• Rear door: keep closed against bag, plug, or discharge hardware.

Keep control cables outside handle pivots when folding or unfolding. Pinched cables can prevent reliable stopping.

Routine maintenance

Remove both batteries and the safety key before maintenance. Brush the steel deck after each use, especially around the rear discharge tunnel and wheel housings. Steel decks tolerate scraping, but exposed scratches should be dried and monitored for rust. Avoid spraying water into battery compartments, switches, cable entries, or the motor cover. Self-propel parts also need periodic inspection because grass and cord can wrap around drive wheels.

• Clean clippings from the deck, bag frame, and discharge door.
• Inspect wheel drive for wrapped string or vine.
• Check blade bolt, handle locks, and cable routing.
• Store batteries indoors, away from heat and freezing conditions.
• Dry the bag before storage to prevent mildew and poor airflow.

At season end, clean thoroughly, remove batteries, charge packs per battery guidance, and store the mower dry.

Blade or chain replacement

This mower uses a single cutting blade, not a chain. Replace the blade if it is bent, cracked, deeply nicked, rusted thin, or still vibrates after balancing. Remove both 20V Max batteries, pull the safety key, and wear gloves. Tip the mower only as recommended so controls and battery compartments stay dry. Block the blade with wood before loosening the blade bolt.

• Use a 21" blade matched to the DCMW220 steel deck.
• Note blade orientation before removal; lift sails face the deck.
• Replace damaged blade adapters, washers, or bolts.
• Tighten to the DeWalt service torque if listed for the blade bolt; do not substitute a generic value.
• Spin the blade by hand before reinstalling batteries.

After replacement, test on a clear patch and stop immediately if vibration appears.

Sharpening or cleaning

Sharpen only a structurally sound blade. Remove it from the mower, clean it, and restore the original bevel with light passes from a file or grinder. Keep both ends equal and balance before installation; imbalance is harder on a steel-deck self-propelled mower because vibration travels through the drive frame and handle. Do not overheat the edge, and do not sharpen into cracks or severe impact dents.

• Scrape the underside with a plastic or wooden tool first.
• Remove wet clumps from the rear door and bag inlet.
• File both cutting edges evenly.
• Balance the blade after sharpening.
• Coat bare deck scratches lightly with rust-preventive care approved for mower decks.

For best cut quality, sharpen before grass tips look torn or pale after mowing.

Troubleshooting

If the mower will not start, check both battery packs, the safety key, battery-cover seating, and the exact start sequence. A two-pack mower may refuse to run correctly when one pack is discharged or not fully latched. If the self-propel drive feels weak, inspect wheel areas for wrapped debris and confirm the drive control moves freely. Heavy grass can trip overload protection; raise the deck and reduce walking speed.

• No start: reseat both 20V Max packs and check key/bail operation.
• Short runtime: sharpen blade, clean deck, and mow dry grass.
• Poor bag fill: empty the 2.0 bushel bag and clear the tunnel.
• Uneven cut: match all wheel-height positions and inspect blade straightness.
• Drive issue: remove debris from drive wheels and check cable movement.

Stop use if smoke, electrical odor, or severe vibration occurs.

Compatible parts

Order mower parts by model, deck width, and drive configuration. The DCMW220 steel deck uses a 21" blade path and a bag sized for its rear discharge opening; a similar-looking part from a push mower can fit poorly or block airflow. Keep wear parts available if the mower handles thick seasonal growth or multiple properties.

• AP—21MB—STL: 21" mower blade for compatible steel-deck setups.
• AP—CLUT—DCMW: self-propel clutch or drive service part for DeWalt mower applications.
• AP—BAG—DW: DeWalt-compatible replacement grass bag.
• Battery system: two compatible 20V Max packs used together.
• Maintenance supplies: blade balancer, plastic scraper, dry brush, and rust-preventive deck care.

Before ordering, match DCMW220, 21" cutting width, bag frame shape, and self-propel hardware.