Murray 7800204 Lawn Mower Manual

The Murray 7800204 is a 20-inch push lawn mower featuring a 140cc Briggs & Stratton engine, 3-in-1 mulching/bagging/side-discharge capability, single-lever height adjustment (6 positions: 1.5"-3.75"), durable steel deck, easy-start system, and large rear wheels for maneuverability. 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 Function Setup 8. Maintenance Schedule 9. Storage & Winterization 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: 140cc Briggs & Stratton engine, 20-inch steel cutting deck, Rear grass bag, Mulching plug, Side discharge chute, Single-lever height adjuster, Push handle with safety bail.

Feature	Description
Engine	140cc Briggs & Stratton 4-cycle, easy-start system
Cutting Width	20 inches
Cutting Deck	Durable steel construction
Cutting Options	3-in-1 (Mulch, Bag, Side Discharge)
Height Adjustment	Single lever, 6 positions (1.5" to 3.75")
Wheels	Large 8-inch rear wheels for easy pushing
Handle	Foldable push handle with ergonomic grips
Safety Bail	Must be engaged to start and run engine
Fuel Tank	0.5-gallon capacity
Oil Type	SAE 30 (summer) / 5W-30 (winter)

Assembly Instructions

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

Attach Handle: Insert lower handle into deck brackets, secure with provided bolts and wing nuts.
Install Upper Handle: Connect upper handle section to lower handle, tighten knobs.
Attach Grass Bag: Hook bag onto rear deck brackets, ensure secure fit.
Install Side Discharge Chute: If using, attach to side discharge port.
Insert Mulching Plug: For mulching, insert plug into rear discharge opening.
Add Oil & Fuel: Add SAE 30 oil to full mark on dipstick. Add fresh unleaded gasoline (no ethanol recommended).

WARNING! Do not add fuel or oil indoors. Keep away from sparks or flames. Ensure all fasteners are tight.

Safety Information

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

Clear Area: Remove stones, sticks, wire, and other objects from lawn.
Check Guards: Ensure all safety guards and shields are in place.
Start Safely: Stand behind mower, engage safety bail, pull starter cord.
Operate Carefully: Do not mow wet grass. Push, do not pull mower. Watch for obstacles.
Stop Engine: Release safety bail to stop blade and engine.
Children & Pets: Keep away from mowing area.

CAUTION! Never remove grass bag or unclog chute with engine running. Disconnect spark plug wire before performing maintenance.

Specifications

Model: Murray 7800204
Engine: Briggs & Stratton 140cc 4-cycle
Cutting Width: 20 inches
Cutting Height: 1.5" - 3.75" (6 positions)
Deck Material: Steel
Wheels: 8-inch rear, 7-inch front
Cutting Options: Mulch, Bag, Side Discharge
Fuel Capacity: 0.5 gallons
Oil Capacity: 20 oz (0.6 liters)
Weight: 55 lbs (approx.)

Controls and Operation

Handle Controls: Safety Bail (must be held to handle), Throttle Control, Height Adjustment Lever.

Starting Procedure:

Check oil and fuel levels.
Move throttle to FAST position.
Prime engine (if equipped) by pressing primer bulb 3 times.
Stand behind mower, grip handle, engage safety bail.
Pull starter cord briskly. Do not allow cord to snap back.

Stopping: Release safety bail. Engine and blade will stop within 3 seconds.

Cutting Height Adjustment

Single-Lever Adjustment: Located near each wheel.

Stop engine and wait for blade to stop completely.
Pull lever outward and move to desired height position (1-6).
Release lever to lock into position.
Adjust all four wheels to same height for even cut.

Height Positions: 1 (1.5"), 2 (2.0"), 3 (2.5"), 4 (2.75"), 5 (3.25"), 6 (3.75").

Tip: For first mow of season or very tall grass, use highest setting, then lower for subsequent mows.

3-in-1 Function Setup

Configure for mulching, bagging, or side discharge.

Mulching: Install mulching plug in rear discharge opening. Remove grass bag and side chute. Cuts clippings finely and returns to lawn.
Bagging: Remove mulching plug. Attach grass bag to rear brackets. For best results, empty bag when 2/3 full.
Side Discharge: Remove mulching plug and grass bag. Attach side discharge chute to port on right side of deck.

WARNING! Always stop engine before changing cutting mode. Ensure attachments are securely installed.

Maintenance Schedule

Regular maintenance ensures long life and safe operation.

Task	Frequency
Check oil level	Before each use
Check for loose fasteners	Before each use
Clean underside of deck	After each use (when cool)
Sharpen or replace blade	Every 25 hours or when dull
Change oil	First 5 hours, then every 50 hours
Replace air filter	Every season or 25 hours
Replace spark plug	Every season or 100 hours
Check wheel bearings	Every season

Storage & Winterization

Prepare mower for extended storage (over 30 days).

Run engine to warm oil, then drain completely. Refill with fresh oil.
Add fuel stabilizer to tank, run engine 2 minutes to circulate. Or, drain fuel tank and carburetor completely.
Remove spark plug, add 1 tablespoon of oil to cylinder, pull starter cord slowly to coat, reinstall plug.
Clean entire mower, especially underside of deck.
Sharpen blade and balance.
Store in clean, dry place, covered.

CAUTION! Never store mower with fuel in tank indoors or in enclosed spaces. Gasoline fumes are explosive.

Warranty Information

Murray 7800204 Lawn Mower is covered by a 2-year limited warranty for residential use. Warranty covers defects in materials and workmanship. Not covered: normal wear, misuse, neglect, commercial use, improper maintenance. Proof of purchase required. For warranty service, contact Murray Customer Service at 1-800-800-7310 or visit www.murray.com. Keep this manual and receipt for reference.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, old fuel, clogged air filter, spark plug fault, safety bail not engaged	Check fuel, use fresh gas. Clean/replace air filter. Check spark plug gap/replace. Ensure safety bail is fully engaged.
Engine runs poorly	Dirty air filter, old fuel, clogged fuel line, dirty spark plug	Clean air filter. Drain old fuel. Check fuel line. Clean/replace spark plug.
Uneven cut	Dull blade, uneven tire pressure, deck clogged, wrong cutting height	Sharpen/balance blade. Check tire pressure. Clean deck underside. Adjust all wheels to same height.
Excessive vibration	Loose blade, bent blade, debris wrapped around blade spindle	Stop engine, disconnect spark plug. Tighten blade bolt (clockwise). Replace bent blade. Remove debris.
Grass not discharging	Wet grass, deck clogged, engine speed too low, dull blade	Mow when grass is dry. Clean deck. Run at FULL throttle. Sharpen blade.

Service: For repairs not covered here, contact authorized Murray service center. 1-800-800-7310; www.murray.com