Craftsman M320 163 CC Lawn Mower Manual

The Craftsman M320 is a 21-inch push lawn mower powered by a 163cc Briggs & Stratton engine, featuring a 3-in-1 discharge system (mulch/bag/side discharge), 6-position single-lever height adjustment, durable steel deck, easy-start system, and large-capacity grass bag. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

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 Discharge System 8. Maintenance Schedule 9. Storage & Winterization 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: 163cc Briggs & Stratton engine, 21-inch steel cutting deck, 3-in-1 discharge system, single-lever height adjustment, rear bag, mulch plug, side discharge chute, and recoil start.

Feature	Description
Engine	163cc Briggs & Stratton 675 Series, OHV
Cutting Width	21 inches
Cutting Deck	Durable steel construction
Discharge System	3-in-1 (Mulch, Bag, Side Discharge)
Height Adjustment	Single-lever, 6 positions (1.25" - 3.75")
Start Type	Recoil (Easy-Pull)
Grass Bag Capacity	2.1 bushels (rear bag)
Wheels	8-inch rear, 7-inch front
Handle	Foldable, adjustable
Fuel Tank	1.1 quarts

Assembly Instructions

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

Attach the handle: Align lower handle with deck brackets, secure with bolts and wing nuts.
Install the upper handle: Connect to lower handle, secure with provided hardware.
Attach the grass bag: Hang bag frame on rear deck hooks, attach bag to frame.
Install the mulch plug (if mulching): Insert into rear discharge opening.
Install side discharge chute (if side discharging): Attach to deck opening.
Add oil and fuel: Fill engine with SAE 30 oil (check dipstick). Add fresh unleaded gasoline (87 octane or higher).

WARNING! Do not add fuel or oil indoors or near ignition sources. Keep hands clear of cutting blade during assembly.

Safety Information

Read all instructions before operation. Always wear appropriate safety gear.

Clear mowing area of debris, rocks, and toys before starting.
Never mow wet grass; ensure firm footing on slopes.
Keep hands and feet away from rotating blade and discharge chute.
Stop engine and wait for blade to stop before crossing gravel drives, roads, or removing grass bag.
Do not allow children or pets in mowing area.
Use hearing and eye protection.

CAUTION! Gasoline is flammable. Store fuel in approved container away from heat and sparks.

Specifications

Engine: Briggs & Stratton 675 Series, 163cc, OHV
Cutting Width: 21 inches
Cutting Heights: 6 positions, 1.25" to 3.75"
Deck Material: Steel
Discharge Options: Mulch, Bag (2.1 bushel), Side Discharge
Start System: Recoil
Wheels: 8-inch rear, 7-inch front
Fuel Type: Unleaded gasoline (87 octane or higher)
Oil Type: SAE 30 (summer), check manual for temperature variants
Weight: Approximately 65 lbs (without bag)

Controls and Operation

Handle Controls: Engine control lever (combines throttle and stop), drive control bar (self-propelled models only), height adjustment lever.

Starting Procedure:

Check oil and fuel levels.
Prime engine (if equipped) by pressing primer bulb 3 times.
Set throttle to FAST position.
Pull recoil starter handle firmly until engine starts.

Stopping: Release drive control (if engaged), move engine control lever to STOP. Wait for blade to stop completely.

Cutting Height Adjustment

Single-lever adjustment changes height for all four wheels simultaneously.

Stop engine and wait for blade to stop.
Pull height adjustment lever toward wheel.
Move lever to desired position (1-6, lowest to highest).
Release lever to lock into place.

Tip: For first mow of season or overgrown grass, set to highest setting, then lower for subsequent passes.

3-in-1 Discharge System

Configure mower for mulching, bagging, or side discharge.

Mulching: Install mulch plug in rear discharge opening. Blade circulates clippings for fine cut and natural fertilizer.
Bagging: Remove mulch plug, attach grass bag to rear hooks. Collects clippings for disposal.
Side Discharge: Remove mulch plug and bag, attach side discharge chute. Ejects clippings to the side.

WARNING! Always stop engine before changing discharge configuration. Ensure chute or plug is securely installed.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Interval	Task
Before each use	Check oil level, inspect blade for damage, clear deck of debris
Every 25 hours	Change engine oil (or annually)
Every season	Replace air filter, spark plug
As needed	Sharpen or replace blade, check tire pressure
After each use	Clean underside of deck, empty grass bag

Blade Sharpening/Replacement: Disconnect spark plug wire. Remove blade bolt (clockwise threads), sharpen at 30-degree angle or replace if damaged. Re-torque to 45-55 ft-lbs.

Storage & Winterization

Prepare mower for extended storage (especially winter).

Run engine to burn remaining fuel in carburetor, or add fuel stabilizer to fresh gas and run for 5 minutes.
Change engine oil (if due).
Clean mower thoroughly, especially underside of deck.
Remove spark plug, add 1 teaspoon of oil into cylinder, pull starter slowly to coat, reinstall plug.
Store in dry, covered area, with bag and chute removed.

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

Warranty Information

Craftsman M320 includes a limited warranty. Residential use: 2-year limited warranty on mower, engine covered by Briggs & Stratton warranty (terms apply). Proof of purchase required. For warranty service, contact Craftsman customer service or an authorized service center. This product is intended for consumer residential use only. Commercial use may void warranty.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, old gas, clogged air filter, spark plug	Add fresh fuel, clean/replace air filter, check/replace spark plug.
Engine runs poorly	Dirty air filter, old fuel, carburetor issue	Clean air filter, use fresh gas, consider carburetor cleaning.
Uneven cutting	Dull blade, uneven tire pressure, low speed	Sharpen/replace blade, inflate tires evenly, mow at full throttle.
Excessive vibration	Loose or damaged blade, debris under deck	Stop engine, check blade tightness and balance, clean deck.
Grass not discharging	Wet grass, clogged deck, dull blade	Mow when grass is dry, clean deck, sharpen blade.

Service: For repairs not covered in manual, contact Craftsman Customer Support at 1-888-331-4569 or visit www.craftsman.com.