Craftsman M100 140cc Lawn Mower Manual

The Craftsman M100 is a 140cc gas-powered walk-behind lawn mower featuring a Briggs & Stratton engine, 21-inch steel cutting deck, 3-in-1 mulching/bagging/side discharge capability, single-lever height adjustment, easy pull-start system, and durable rear-wheel drive. This manual covers safety instructions, assembly, operation, maintenance, troubleshooting, and specifications to ensure proper and safe use.

1. Features at a Glance 2. Assembly Instructions 3. Safety Information 4. Specifications 5. Controls and Operation 6. Cutting Height Adjustment 7. 3-in-1 Deck Function 8. Maintenance Schedule 9. Storage Guidelines 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: 140cc Briggs & Stratton engine, 21-inch steel deck, rear bagger, mulch plug, side discharge chute, single-lever height adjuster, 8-inch rear wheels, 7-inch front wheels, recoil starter, and fuel tank with gauge.

Feature	Description
Engine	140cc Briggs & Stratton 450E Series, OHV
Cutting Width	21 inches
Cutting Deck	3-in-1 (Mulch, Bag, Side Discharge)
Height Adjustment	Single lever, 6 positions (1.25" - 3.75")
Drive System	Rear-wheel drive
Wheels	8" rear, 7" front
Starter	Recoil pull-start
Fuel Tank	1.1 quarts with gauge
Bag Capacity	2.5 bushels
Weight	Approx. 65 lbs

Assembly Instructions

Unpack all parts from box. Verify contents against parts list.

Attach handle: Insert lower handle into deck brackets, secure with provided bolts and wing nuts.
Install upper handle: Connect to lower handle, tighten knobs.
Attach grass bag: Hook bag frame onto rear deck brackets; ensure bag is securely attached.
Install side discharge chute: If using, attach to deck opening with provided hardware.
Insert mulch plug: For mulching, place plug into rear discharge opening.
Add oil and fuel: Fill engine with SAE 30 oil (check dipstick). Add fresh unleaded gasoline (87 octane or higher).

WARNING! Wear gloves during assembly. Ensure all fasteners are tight before operation.

Safety Information

Read all instructions before operating. Keep bystanders and pets away.

Clear mowing area of stones, toys, and debris.
Wear sturdy shoes, eye protection, and long pants.
Never operate without grass bag, mulch plug, or discharge chute properly installed.
Do not mow wet grass.
Stop engine and wait for blades to stop before crossing gravel drives or roads.
Never leave mower unattended with engine running.

DANGER! Keep hands and feet away from rotating blades. Disconnect spark plug wire before performing maintenance.

Specifications

Engine: Briggs & Stratton 450E Series, 140cc, OHV
Cutting Width: 21 inches
Cutting Height Range: 1.25" - 3.75" (6 positions)
Deck Material: Steel
Drive: Rear-wheel drive
Wheels: 8" rear, 7" front
Fuel Capacity: 1.1 quarts
Oil Capacity: 20 oz (SAE 30)
Bag Capacity: 2.5 bushels
Weight: 65 lbs (approx.)
Warranty: 2-year limited

Controls and Operation

Handle Controls: Drive control lever (bail), height adjustment lever, recoil starter grip.

Starting: 1. Check oil and fuel. 2. Push primer bulb 3 times (cold engine). 3. Set throttle to FAST. 4. Pull recoil starter firmly. Stopping: Release drive bail; move throttle to STOP.

Operation: To move forward, squeeze drive bail against handle. Release to stop drive. Adjust speed by varying pressure on bail. For turns, release bail, pivot mower, re-engage.

Cutting Height Adjustment

Single-lever adjustment: Move lever to one of 6 positions.

Stop engine and wait for blade to stop.
Pull lever outward and move to desired height setting.
Release lever to lock into position.
Settings range from 1.25" (lowest) to 3.75" (highest).

Tip: For first mow of season, set to highest setting. Never remove more than 1/3 of grass blade length at one time.

3-in-1 Deck Function

Configure for mulching, bagging, or side discharge.

Mulching: Install mulch plug in rear discharge opening. Grass is cut finely and returned to lawn as fertilizer.
Bagging: Remove mulch plug, attach grass bag to rear brackets. Collects clippings for disposal.
Side Discharge: Remove mulch plug and bag, attach side discharge chute. Clippings are expelled to the side.

WARNING! Always have one of the three configurations properly installed. Never operate with discharge openings uncovered.

Maintenance Schedule

Regular maintenance ensures long life and safe operation.

Task	Frequency
Check oil level	Before each use
Check for loose fasteners	Weekly
Clean underside of deck	After each use
Sharpen/replace blade	Every 25 hours or as needed
Replace air filter	Every season or 25 hours
Change oil	First 5 hours, then every 50 hours
Replace spark plug	Every 100 hours
Lubricate wheels & height adjuster	Every 25 hours

Storage Guidelines

Prepare mower for off-season storage.

Run engine to burn off remaining fuel, or add fuel stabilizer to full tank and run for 5 minutes.
Change oil and replace air filter.
Remove spark plug, add 1 tablespoon of oil into cylinder, pull starter slowly to coat, reinstall plug.
Clean deck thoroughly, dry, and apply light oil to prevent rust.
Store in cool, dry place, covered.

CAUTION! Never store with fuel in tank over 30 days without stabilizer. Gasoline can deteriorate and damage engine.

Warranty Information

Craftsman M100 includes a 2-year limited warranty covering defects in materials or workmanship under normal residential use. Proof of purchase required. Warranty does not cover normal wear, misuse, commercial use, or lack of maintenance. For warranty service, contact Craftsman Customer Support at 1-888-331-4569 or visit www.craftsman.com. Keep this manual and receipt for reference.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, old gas, clogged air filter, spark plug	Check fuel; use fresh gas. Clean/replace air filter. Check/replace spark plug.
Engine runs poorly	Dirty air filter, old fuel, carburetor issue	Replace air filter. Drain old gas. Clean carburetor if needed.
Uneven cut	Dull blade, uneven tire pressure, deck not level	Sharpen/replace blade. Check tire pressure. Level deck.
Mower vibrates excessively	Loose blade, bent blade, debris under deck	Tighten blade bolt. Replace bent blade. Clean deck.
Won't drive	Drive cable loose or broken	Adjust or replace drive cable.
Grass not discharging	Wet grass, deck clogged, dull blade	Mow when dry. Clean deck. Sharpen blade.

Service: For technical support, call 1-888-331-4569 or visit www.craftsman.com.