Murray 866079-00 Lawn Mower Manual

The Murray 866079-00 is a walk-behind, gas-powered lawn mower featuring a Briggs & Stratton engine, 21-inch steel cutting deck, single-lever height adjustment (6 positions), rear bagging system, mulching capability, and side discharge chute. It includes safety features like blade control system, operator presence control, and durable pneumatic tires. 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. Grass Collection & Discharge 9. Safety Features 10. Care & Maintenance 11. Warranty Information 12. Troubleshooting

Features at a Glance

Key components: Briggs & Stratton engine, 21-inch steel deck, Height adjustment lever, Rear grass bag, Side discharge chute, Blade control handle, Pneumatic tires.

FeatureDescription
EngineBriggs & Stratton 125cc gas engine with easy-start system
Cutting Deck21-inch stamped steel, rust-resistant
Cutting HeightSingle-lever adjustment, 6 positions (1.5" to 3.75")
Grass CollectionRear bag with 2.1 bushel capacity
Discharge OptionsSide discharge chute for mulching or bagging
Blade ControlOperator presence control system (deadman's switch)
Tires8-inch front, 10-inch rear pneumatic tires
Fuel Tank0.5-gallon capacity
WeightApproximately 65 lbs
Warranty2-year limited warranty

Assembly Instructions

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

  1. Attach handle: Insert lower handle into deck brackets, secure with bolts and wing nuts.
  2. Install grass bag: Hook bag frame onto rear deck mounts; ensure secure attachment.
  3. Attach side discharge chute: Slide chute into side port; secure with provided pin.
  4. Install height adjustment lever: Connect to deck linkage as per diagram.
  5. Add engine oil: Fill with SAE 30 detergent oil (check dipstick).
  6. Add gasoline: Use fresh unleaded gasoline (87 octane minimum).

WARNING! Always wear gloves during assembly. Ensure all bolts are tightened securely.

First-Time Setup

Before first use, complete pre-operation checks.

  1. Check oil level: Ensure oil is at full mark on dipstick.
  2. Fuel: Fill tank with fresh unleaded gasoline (no ethanol recommended).
  3. Blade inspection: Ensure cutting blade is properly installed and sharp.
  4. Tire pressure: Inflate tires to 20 PSI (check sidewall).
  5. Height adjustment: Test all 6 cutting height positions.
  6. Safety check: Verify blade control system engages/disengages properly.

CAUTION! Never add fuel while engine is hot or running. Allow engine to cool completely.

Specifications

Controls and Operation

Main controls: Blade control handle, Throttle control, Choke, Primer bulb, Height adjustment lever.

Starting Procedure:

  1. Check oil and fuel levels.
  2. Move throttle to FAST position.
  3. Press primer bulb 3 times (cold engine).
  4. Pull choke to ON position (cold engine).
  5. Hold blade control handle against handlebar.
  6. Pull starter rope briskly.
  7. Once started, move choke to OFF.

Stopping: Release blade control handle; move throttle to STOP position.

Cutting Height Adjustment

Single-lever system adjusts all four wheels simultaneously.

  1. Stop engine and wait for blade to stop completely.
  2. Pull height adjustment lever toward wheel.
  3. Move lever to desired position (1-6).
  4. Release lever to lock in position.
  5. Test by lifting rear of mower and spinning wheels.

Height Positions: 1 (1.5"), 2 (2"), 3 (2.5"), 4 (2.75"), 5 (3.25"), 6 (3.75")

Grass Collection & Discharge

Three cutting options: Bagging, Mulching, Side discharge.

  1. Bagging: Install rear bag; ensure chute is closed.
  2. Mulching: Install mulching plug (sold separately).
  3. Side Discharge: Remove bag; install side discharge chute.
  4. Empty bag when ¾ full for optimal performance.
  5. Clean bag after each use to prevent mold.

Tip: Cut when grass is dry for best collection results.

Safety Features

Blade Control System: Blade stops within 3 seconds of releasing handle. Operator Presence Control: Engine stops if operator leaves position. Safety Labels: Read and understand all warning labels. Protective Footwear: Always wear sturdy shoes while operating.

Care & Maintenance

Regular maintenance ensures optimal performance and longevity.

After Each Use:

Monthly:

Seasonal:

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

Warranty Information

Murray 866079-00 comes with a 2-year limited warranty covering defects in materials and workmanship. Warranty does not cover normal wear, misuse, or lack of maintenance. For warranty claims, contact Murray Customer Service at 1-800-800-7310 or visit www.murray.com. Keep original receipt as proof of purchase.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startNo fuel, bad spark plug, clogged air filterCheck fuel level; inspect spark plug; clean/replace air filter.
Engine runs poorlyDirty air filter, old gasoline, water in fuelClean air filter; drain old gas; add fresh fuel.
Uneven cuttingDull blade, uneven tire pressure, deck cloggedSharpen/replace blade; inflate tires evenly; clean deck.
Excessive vibrationLoose blade, bent blade, unbalanced bladeTighten blade bolts; replace bent blade; balance blade.
Bag not fillingWet grass, clogged chute, full bagCut when grass is dry; clear chute; empty bag.
Self-propelled not workingDrive belt worn, drive cable looseReplace drive belt; adjust drive cable tension.

Service: For technical support, call 1-800-800-7310 or visit www.murray.com

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