Murray MP675RMD21H Lawn Mower Manual

The Murray MP675RMD21H is a 21-inch, 6.75 HP Briggs & Stratton-powered rear bagging push mower with a 3-in-1 cutting system (mulch, bag, side discharge), 2.1 bushel capacity bag, 7-position single-lever height adjustment (1.25-3.75 inches), durable steel deck, easy-start engine, and ergonomic handle with auto-stop safety feature. 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 System Setup 8. Maintenance Schedule 9. Storage Instructions 10. Safety Information 11. Warranty Information 12. Troubleshooting

Features at a Glance

Key components: 6.75 HP Briggs & Stratton engine, 21-inch steel cutting deck, rear grass bag, 3-in-1 cutting system, single-lever height adjustment, ergonomic handle with auto-stop.

FeatureDescription
Engine6.75 HP Briggs & Stratton 4-cycle engine
Cutting Width21-inch steel deck
Cutting System3-in-1 (mulch, bag, side discharge)
Height AdjustmentSingle-lever, 7 positions (1.25-3.75 inches)
Grass Bag2.1 bushel rear bag with easy-empty feature
Starting SystemRecoil start with primer bulb
Safety FeatureAuto-stop blade when handle released
Wheels8-inch rear, 7-inch front
WeightApproximately 65 lbs
Fuel Capacity1 quart gasoline tank

Assembly Instructions

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

  1. Attach handle: Align lower handle with deck brackets, secure with bolts and wing nuts.
  2. Install upper handle: Connect to lower handle, secure with provided hardware.
  3. Attach grass bag: Hook bag frame onto rear deck brackets, ensure secure latch.
  4. Install side discharge chute (if not mulching/bagging): Attach to discharge opening.
  5. Add engine oil: Fill with SAE 30 detergent oil (check dipstick for level).
  6. Add gasoline: Use fresh unleaded gasoline (no ethanol recommended).

WARNING! Do not add gasoline during assembly. Keep away from sparks or flames.

First-Time Setup

Before first use, complete final checks and adjustments.

  1. Check oil level: Ensure oil is at full mark on dipstick.
  2. Check tire pressure: Inflate to 20 PSI (recommended).
  3. Adjust cutting height: Set lever to desired position (middle recommended for first mow).
  4. Test safety features: Engage handle; blade should stop within 3 seconds of release.
  5. Prime engine: Press primer bulb 3 times for cold start.
  6. Start engine: Pull recoil starter firmly.

CAUTION! Always mow in clear daylight. Remove stones, toys, and debris from lawn first.

Specifications

Controls and Operation

Handle controls: Auto-stop bail (must be held to run), height adjustment lever, primer bulb, recoil starter.

Starting: 1. Check oil and fuel. 2. Move to clear area. 3. Set height. 4. Prime 3x (cold). 5. Pull starter. Stopping: Release bail handle; engine and blade stop.

Height Adjustment: Single lever controls all four wheels. Move lever to desired number (1=lowest, 7=highest). Cutting Mode: Install mulch plug for mulching; attach bag for collection; install side chute for discharge.

Cutting System Setup

Configure for mulching, bagging, or side discharge.

  1. Mulching: Install mulch plug over discharge opening. Ensure bag is removed.
  2. Bagging: Attach grass bag to rear brackets. Ensure chute and plug are removed.
  3. Side Discharge: Install discharge chute. Ensure bag and mulch plug are removed.

Tip: For best results, mow when grass is dry. Never remove more than 1/3 of grass height at once.

Maintenance Schedule

Regular maintenance ensures long life and optimal performance.

  1. Before each use: Check oil level, tire pressure, blade condition, and clear deck of debris.
  2. Every 25 hours: Change engine oil (or seasonally).
  3. Every season: Replace air filter, spark plug. Sharpen or replace blade.
  4. As needed: Clean underside of deck, check bolts/nuts for tightness.
  5. Storage: Run engine dry or add fuel stabilizer.

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

Storage Instructions

Prepare mower for off-season storage.

  1. Clean: Remove all grass and debris from deck, bag, and engine.
  2. Fuel: Either run engine until tank is empty, or add fuel stabilizer to full tank and run for 2 minutes.
  3. Oil: Change oil if not done recently.
  4. Spark Plug: Remove and add 1 teaspoon of oil into cylinder; pull starter slowly to distribute.
  5. Store: In dry, covered area. Cover mower to prevent dust.

CAUTION! Store gasoline only in approved containers away from living areas.

Safety Information

Read and follow all safety rules in manual.

DANGER! Blade rotates at high speed. Serious injury can occur if safety rules are ignored.

Warranty Information

Murray mowers are backed by a limited warranty. For residential use, the engine is covered by Briggs & Stratton warranty (typically 2 years), and the mower deck/hardware by Murray (typically 2 years). Proof of purchase required. For warranty service, contact an authorized Murray service center. For support, visit www.murray.com or call 1-800-800-7310.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startNo fuel, old gas, clogged filter, bad spark plugCheck fuel; use fresh gas; clean/replace air filter; check spark plug.
Engine runs poorlyDirty air filter, old gasolineReplace air filter; drain and refill with fresh gasoline.
Uneven cuttingDull blade, uneven tire pressure, low cutting heightSharpen/replace blade; inflate tires evenly; raise cutting height.
Bag not fillingWet grass, clogged deck, full bagMow when dry; clean deck underside; empty bag frequently.
Vibration/excessive noiseLoose blade, bent blade, debris in deckStop engine, disconnect spark plug. Tighten or replace blade; clean deck.

Service: For repairs, use authorized Murray service centers. Customer support: 1-800-800-7310; www.murray.com

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