Murray Mulcher 20-inch Push Lawn Mower Manual

The Murray Mulcher 20-inch Push Lawn Mower is a reliable, gas-powered walk-behind mower featuring a Briggs & Stratton engine, 20-inch steel cutting deck, 3-in-1 mulching/bagging/side-discharge capability, single-lever height adjustment (1.5-4 inches), push-button start, durable 10-inch rear wheels, and a 2.0-bushel grass bag. Designed for residential lawns up to 1/2 acre. Below are key sections for safety, features, assembly, operation, maintenance, troubleshooting, and specifications.

1. Features at a Glance 2. Assembly Instructions 3. Safety Precautions 4. Specifications 5. Controls and Operation 6. Cutting Height & Modes 7. Engine Operation 8. Maintenance Schedule 9. Storage & Winterization 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: Briggs & Stratton engine, 20-inch steel deck, height adjustment lever, rear grass bag, mulching plug, discharge chute, and push handle.

Feature	Description
Cutting Width	20 inches
Engine	Briggs & Stratton 140cc 4-cycle gas engine
Cutting Modes	Mulch, Bag, Side Discharge (3-in-1)
Height Adjustment	Single lever, 6 positions (1.5" to 4")
Start System	Recoil pull-start with primer bulb
Wheels	10-inch rear, 8-inch front
Grass Bag Capacity	2.0 bushels, easy-remove fabric bag
Deck Material	Powder-coated steel
Handle	Foldable, padded grip
Weight	Approx. 55 lbs

Assembly Instructions

Unpack all parts from box. Assembly requires adjustable wrench and screwdriver (included).

Attach handle: Align lower handle with deck brackets, secure with provided bolts and washers.
Install upper handle: Slide upper handle onto lower handle, secure with knobs.
Attach grass bag: Hook bag frame onto rear deck brackets; ensure fabric bag is secured.
Install mulching plug/discharge chute: For mulching, insert plug into rear deck opening. For side discharge, attach chute to side port.
Check wheels: Ensure all wheels are securely fastened and spin freely.
Add oil and gas: Refer to engine manual for correct oil type (SAE 30) and fill gasoline (unleaded, 87 octane minimum).

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

Safety Precautions

Read all instructions before operation. Always wear sturdy shoes and eye protection.

Clear mowing area: Remove stones, toys, wires, and other debris.
Check fuel: Fill gasoline outdoors, away from ignition sources. Wipe spills immediately.
Start safely: Ensure feet and hands are clear of moving parts. Pull starter cord firmly.
Operate carefully: Mow across slopes, not up/down. Do not mow wet grass.
Keep bystanders away: Especially children and pets.
Stop engine: Before unclogging, adjusting height, or leaving mower unattended.

CAUTION! The blade is sharp. Never place hands or feet under deck while engine is running.

Specifications

Model: Murray Mulcher 20-inch Push
Cutting Width: 20 inches
Engine: Briggs & Stratton 140cc, 4-cycle, OHV
Fuel Type: Unleaded gasoline (87 octane or higher)
Oil Type: SAE 30 (20 oz capacity)
Cutting Height Range: 1.5 to 4 inches (6 positions)
Grass Bag Capacity: 2.0 bushels
Wheel Size: Front 8-inch, Rear 10-inch
Deck Material: Powder-coated steel
Weight: 55 lbs (approx.)
Recommended Lawn Size: Up to 1/2 acre

Controls and Operation

Handle Controls: Engine throttle lever, handlebar grip. Deck Controls: Height adjustment lever, bag attachment hooks.

Starting Procedure:

Check oil and fuel levels.
Move throttle lever to FAST position.
Press primer bulb 3 times (cold engine).
Pull recoil starter cord firmly until engine starts.
Allow engine to warm up 30 seconds before mowing.

Stopping: Move throttle to STOP. Wait for blade to completely stop.

Cutting Height & Modes

Adjust height before starting engine. Use single lever to raise/lower all four wheels simultaneously.

Mulching Mode: Install mulching plug. Cuts clippings finely and returns them to lawn as fertilizer.
Bagging Mode: Attach grass bag. Collects clippings for disposal.
Side Discharge: Install discharge chute. Ejects clippings to side for large or wet grass.

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

Engine Operation

Briggs & Stratton 140cc engine requires regular maintenance.

Break-in period: First 5 hours, vary speed. Change oil after first 5 hours.
Fuel: Use fresh unleaded gasoline. Add fuel stabilizer if storing over 30 days.
Oil: Check level before each use. Change every 25 hours or seasonally.
Air filter: Clean every 25 hours, replace if damaged.
Spark plug: Check gap (0.030"), clean or replace annually.

WARNING! Never run engine indoors or in poorly ventilated areas due to carbon monoxide risk.

Maintenance Schedule

Interval	Task
Before each use	Check oil level, inspect blade for damage, clear deck of debris
Every 25 hours	Change engine oil, clean air filter, check spark plug
Seasonally	Sharpen or replace blade, lubricate wheel axles, inspect cables
As needed	Clean underside of deck, tighten bolts/nuts, replace grass bag if torn

Blade Sharpening: Disconnect spark plug wire. Remove blade with wrench. Sharpen at original angle (balance blade after sharpening).

Storage & Winterization

Prepare mower for off-season storage to prevent damage.

Run engine to warm oil, then drain oil (while warm). Refill with fresh oil.
Add fuel stabilizer to gas tank, run engine 5 minutes to circulate.
Either drain fuel tank completely or fill to top to prevent condensation.
Remove spark plug, add 1 teaspoon of oil into cylinder, pull starter cord slowly to coat, reinstall plug.
Clean entire mower, especially underside of deck.
Store in dry, covered area, preferably off concrete floor.

CAUTION! Gasoline is flammable. Allow engine to cool completely before storage.

Warranty Information

Murray mowers are backed by a limited warranty. Residential use: 2-year limited warranty on mower, engine warranty provided by Briggs & Stratton (typically 2 years). Proof of purchase required. Warranty does not cover normal wear, misuse, or lack of maintenance. For warranty service, contact an authorized Murray service center. 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 issue	Check fuel level, use fresh gas, clean/replace air filter, check spark plug gap/connection.
Engine runs poorly or stalls	Dirty air filter, water in fuel, clogged carburetor	Clean air filter, drain fuel tank, add fresh gas, consider carburetor cleaner.
Uneven cutting	Dull blade, uneven tire pressure, deck clogged	Sharpen/replace blade, check tire pressure, clean underside of deck.
Excessive vibration	Loose blade, bent blade, debris stuck	Stop engine, disconnect spark plug. Tighten blade bolt or replace bent blade.
Grass not bagging/mulching well	Wet grass, deck clogged, engine speed too low	Mow when dry, clean deck, run engine at FAST throttle setting.
Wheels not turning freely	Debris in axles, lack of lubrication	Clean axles, apply light oil or silicone spray.

Service: For engine-specific issues, refer to Briggs & Stratton manual. For mower parts, visit www.murray.com or contact 1-800-XXX-XXXX.