Murray 309007x51A Lawn Mower Manual

The Murray 309007x51A is a 21-inch push lawn mower featuring a 159cc Briggs & Stratton engine, 3-in-1 mulching, bagging, and side-discharge capability, single-lever height adjustment (6 positions from 1.5" to 3.75"), durable steel deck, easy-start system, and rear-wheel drive. This manual covers safety, assembly, operation, maintenance, troubleshooting, and specifications.

1. Features at a Glance 2. Assembly Instructions 3. First-Time Setup 4. Specifications 5. Controls and Operation 6. Cutting & Discharge Options 8. Maintenance Schedule 9. Storage 10. Safety Information 11. Warranty & Support 12. Troubleshooting

Features at a Glance

Key components: 21-inch steel cutting deck, Briggs & Stratton engine, rear bag, height adjustment lever, drive control bar, and mulching plug.

Feature	Description
Engine	159cc Briggs & Stratton 675 Series, 4-cycle
Cutting Width	21 inches
Cutting Height	6 positions (1.5" - 3.75")
Cutting Options	Mulch, Bag, Side Discharge
Drive System	Rear-wheel drive with drive control bar
Deck Material	Durable steel
Fuel Tank Capacity	Approximately 1 quart
Starter	Recoil with Easy-Spin™ technology
Wheels	8-inch rear, 7-inch front
Weight	Approximately 60 lbs

Assembly Instructions

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

Attach Handle: Align lower handle with deck brackets, secure with provided bolts and wing nuts.
Install Upper Handle: Connect upper handle to lower handle, tighten knobs.
Attach Bag: Hang grass bag onto rear bagger brackets; ensure it clicks into place.
Install Mulching Plug (if desired): Insert plug into rear discharge chute.
Add Oil & Fuel: Add SAE 30 motor oil to engine (check dipstick). Add fresh unleaded gasoline (87 octane minimum).

WARNING! Do not add fuel or oil indoors or near ignition sources. Ensure mower is on level surface during assembly.

First-Time Setup

Before first use, complete final checks and adjustments.

Check Oil Level: Ensure oil is at full mark on dipstick.
Check Tire Pressure: Inflate all tires to 20 PSI.
Adjust Cutting Height: Set lever to desired height (middle position recommended for first mow).
Test Controls: Squeeze drive control bar to ensure wheels engage; release to disengage.
Start Engine: Follow starting procedure in Controls section.

CAUTION! Never operate mower without proper oil level. Clear mowing area of debris before starting.

Specifications

Model: Murray 309007x51A
Engine: Briggs & Stratton 675 Series, 159cc, 4-cycle
Cutting Width: 21 inches
Cutting Height Range: 1.5" to 3.75" (6 positions)
Deck Material: 20-gauge steel
Drive: Rear-wheel drive
Wheels: 8" rear, 7" front
Fuel Type: Unleaded gasoline (87 octane or higher)
Oil Type: SAE 30 (above 40°F) or 10W-30 (variable temps)
Bag Capacity: 2.1 bushels

Controls and Operation

Primary controls: Drive control bar, height adjustment lever, engine controls.

Starting Procedure:

Ensure spark plug wire is connected.
Move throttle control to FAST position.
Prime engine (if equipped) by pressing primer bulb 3 times.
Pull recoil starter handle briskly.

Stopping: Release drive control bar, move throttle to STOP, disconnect spark plug wire for safety.

Height Adjustment: Single lever adjusts all four wheels simultaneously. Select position for grass condition.

Cutting & Discharge Options

Configure mower for mulching, bagging, or side discharge.

Mulching: Install mulching plug in rear discharge chute. Grass is cut finely and returned to lawn as fertilizer.
Bagging: Attach grass bag to rear brackets. Collect clippings for disposal.
Side Discharge: Remove mulching plug and bag. Clippings discharge from side chute (use with optional side discharge deflector).

Tip: For best mulching results, mow when grass is dry and don't cut more than 1/3 of grass height at once.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Maintenance Task	Frequency
Check oil level	Before each use
Clean underside of deck	After each use
Check/replace air filter	Every 25 hours
Change engine oil	Every 50 hours or season
Replace spark plug	Every 100 hours or season
Sharpen/replace blade	Every 25 hours or as needed
Check tire pressure	Monthly
Lubricate wheel bearings	Every season

WARNING! Always disconnect spark plug wire before performing any maintenance.

Storage

Proper storage prevents fuel system issues and corrosion.

Run engine to use up remaining fuel, or add fuel stabilizer to full tank.
Change oil if due.
Clean entire mower, especially underside of deck.
Remove spark plug, add 1 tablespoon of oil to cylinder, pull starter slowly to distribute, reinstall plug.
Store in dry, covered area.

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

Safety Information

Read and understand all safety instructions before operation.

Wear sturdy shoes, eye protection, and long pants.
Clear mowing area of stones, toys, and other objects.
Never mow wet grass.
Do not allow children or pets in mowing area.
Always push mower forward; never pull backward while engine is running.
Use extreme caution when mowing on slopes; mow across slopes, not up and down.
Stop engine and wait for blade to stop before crossing gravel drives or roads.
Never remove grass bag or unclog chute while engine is running.

Warranty & Support

Murray mowers are backed by a limited warranty. For warranty service, contact an authorized service center with proof of purchase.

Warranty Coverage: 2-year limited warranty for residential use. Does not cover normal wear, misuse, or lack of maintenance.

Support: For parts, manuals, or service assistance, visit www.murray.com or contact customer service at 1-800-800-7310.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, old fuel, spark plug disconnected, choke/throttle setting	Add fresh fuel, connect spark plug wire, set choke properly, check oil level.
Engine runs poorly	Dirty air filter, old fuel, clogged carburetor	Replace air filter, use fresh fuel, clean carburetor.
Uneven cut	Dull blade, uneven tire pressure, deck clogged	Sharpen/replace blade, inflate tires evenly, clean deck.
Mower vibrates excessively	Loose blade, bent blade, unbalanced blade	Tighten blade bolt, replace bent blade, balance blade.
Won't drive	Drive cable loose or broken, drive belt worn	Adjust or replace drive cable, replace drive belt.
Grass not discharging properly	Wet grass, deck clogged, engine speed too low	Mow when dry, clean deck, run at full throttle.

For Service: 1-800-800-7310; www.murray.com