Murray MP675RM21H Lawn Mower Manual

The Murray MP675RM21H is a 21-inch, 6.75 horsepower rear-engine riding lawn mower designed for residential use. It features a Briggs & Stratton engine, 5-speed manual transmission, single-lever height adjustment, 2-gallon fuel tank, rear bagger attachment capability, and safety features including blade brake clutch and operator presence control. 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. Attachments & Accessories 7. Cutting & Mowing Guide 8. Safety Features 9. Maintenance Schedule 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: Briggs & Stratton 6.75 HP engine, 21-inch steel cutting deck, 5-speed transmission, single-lever height adjustment, rear bagger port, fuel gauge, and safety key.

Feature	Description
Engine	Briggs & Stratton 6.75 HP, 4-cycle, single cylinder
Cutting Width	21 inches
Transmission	5-speed manual, rear-wheel drive
Cutting Height Adjustment	Single lever, 6 positions (1.5" to 4")
Fuel Tank	2-gallon capacity
Starter	Recoil pull-start
Bagging	Rear bagger attachment compatible
Safety Features	Blade brake clutch, operator presence control, safety key
Wheels	Front: 8-inch, Rear: 10-inch
Weight	Approximately 65 lbs

Assembly Instructions

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

Attach handle: Align handle with deck brackets, secure with provided bolts and wrench.
Install wheels: Slide wheels onto axles, secure with washers and cotter pins.
Attach grass bagger (if included): Connect bagger frame to rear port, secure with clips.
Add engine oil: Use SAE 30 oil (approx. 20 oz) as specified in engine manual.
Add fuel: Use unleaded gasoline only, fill to 2-gallon capacity.

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

First-Time Setup

Before first use, complete pre-operation checks.

Check oil level: Use dipstick, add if low.
Check tire pressure: Inflate to 15 PSI (front) and 10 PSI (rear).
Adjust cutting height: Set lever to desired position (start at 3" for first mow).
Test controls: Ensure throttle, choke, and drive engage smoothly.
Start engine: Insert safety key, set choke, pull recoil starter.

CAUTION! Always operate outdoors in well-ventilated area. Keep hands and feet away from moving parts.

Specifications

Model: MP675RM21H
Engine: Briggs & Stratton 6.75 HP, 4-cycle
Cutting Width: 21 inches
Cutting Heights: 1.5" to 4" (6 positions)
Transmission: 5-speed manual
Fuel Capacity: 2 gallons
Oil Capacity: 20 oz (SAE 30)
Wheel Size: Front 8", Rear 10"
Weight: 65 lbs (approx.)
Warranty: 2-year limited

Controls and Operation

Main controls located on handle: Throttle, drive control, height adjustment, safety key.

Starting Procedure: Insert safety key, set choke (cold start), pull recoil starter. Stopping: Release drive control, move throttle to STOP, remove key.

Cutting Height: Adjust with single lever (positions 1-6). Speed Selection: Use gear shift (1-5, R for reverse). Bagging/Mulching: Attach bagger for collection; remove for mulching.

Attachments & Accessories

Compatible with Murray rear bagger (model 94281) and mulch kit (model 94282).

Rear bagger: Attaches to rear port, holds up to 2.5 bushels.
Mulch kit: Replaces bagger, returns clippings to lawn.
Optional: Wheel weights for slopes, blade sharpener kit.

Tip: Ensure engine is off and cool before installing or removing attachments.

Cutting & Mowing Guide

For best results, follow these mowing practices.

Mow when grass is dry to prevent clumping.
Adjust height based on season: higher in summer (3-4"), lower in spring/fall (2-3").
Overlap passes by 2-3 inches for even cut.
Change mowing pattern weekly to avoid ruts.
Empty bagger when 2/3 full to maintain airflow.
On slopes: Mow across slope, not up and down.
Sharp blade: Sharpen or replace blade every 25 hours of use.

WARNING! Do not mow on slopes greater than 15 degrees. Watch for obstacles (rocks, toys) before mowing.

Safety Features

Blade Brake Clutch: Stops blade within 3 seconds when drive control is released. Operator Presence Control: Engine stops if operator leaves seat. Safety Key: Must be inserted to start engine.

Maintenance Schedule

Regular maintenance ensures longevity and performance.

Before each use: Check oil, tire pressure, blade condition.
Every 25 hours: Change oil, sharpen/replace blade, clean deck.
Every 50 hours: Replace air filter, check spark plug.
Every 100 hours: Replace fuel filter, check drive belt.
Seasonal: Drain fuel before storage, lubricate moving parts.

CAUTION! Disconnect spark plug wire before performing any maintenance. Allow engine to cool completely.

Warranty Information

2-year limited warranty for residential use. Warranty covers defects in materials/workmanship. Not covered: normal wear, misuse, commercial use, lack of maintenance. For warranty service, contact Murray customer service at 1-800-800-7310 or visit www.murray.com. Keep original receipt as proof of purchase.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, bad spark plug, safety key not inserted	Check fuel level; inspect spark plug; ensure safety key is inserted.
Poor cutting performance	Dull blade, low engine speed, clogged deck	Sharpen/replace blade; set throttle to FAST; clean underside of deck.
Excessive vibration	Loose blade, unbalanced blade, damaged deck	Tighten blade bolt; balance or replace blade; inspect deck for damage.
Loss of power	Dirty air filter, old fuel, clogged fuel filter	Clean/replace air filter; drain old fuel; replace fuel filter.
Wheels not driving	Drive belt loose or broken, transmission issue	Inspect and adjust/replace drive belt; check transmission linkage.

Reset: For safety system reset, ensure all controls are in neutral, reinsert safety key.

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