Ariens 915265 Lawn Mower Manual

The Ariens 915265 is a 21-inch self-propelled walk-behind lawn mower featuring a 159cc Briggs & Stratton engine, 3-in-1 cutting system (mulch/bag/side discharge), 6-speed drive system, single-lever height adjustment (1.5-4 inches), durable steel deck, easy-start technology, and a 2.5-bushel grass bag. 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 7. Maintenance Schedule 8. Storage Guidelines 9. Safety Information 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: 159cc Briggs & Stratton engine, 21-inch steel cutting deck, 3-in-1 cutting system, 6-speed drive system, single-lever height adjustment, 2.5-bushel grass bag, and easy-start technology.

FeatureDescription
Engine159cc Briggs & Stratton 675 Series engine
Cutting Width21-inch steel deck
Cutting System3-in-1 (mulch, bag, side discharge)
Drive System6-speed self-propelled transmission
Height AdjustmentSingle-lever (1.5 to 4 inches)
Grass Bag2.5-bushel capacity
Starting SystemEasy-start technology
Wheels8-inch rear, 7-inch front
HandleFoldable for storage
Fuel Tank0.95-quart capacity

Assembly Instructions

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

  1. Attach handle: Secure upper and lower handle sections with provided bolts.
  2. Install grass bag: Attach bag support frame to deck, then hook bag onto frame.
  3. Connect drive cable: Route cable from handle to transmission and secure.
  4. Install side discharge chute: Attach to deck opening if using side discharge.
  5. Add engine oil: Fill with SAE 30 detergent oil (20 oz. capacity).
  6. Add fuel: Use fresh unleaded gasoline (87 octane minimum).

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

First-Time Setup

Complete assembly, then prepare for first use.

  1. Check oil level: Ensure oil is at full mark on dipstick.
  2. Add fuel: Fill tank with fresh unleaded gasoline.
  3. Set cutting height: Adjust single lever to desired position (start at 3 inches).
  4. Select cutting mode: Install appropriate accessory (bag, mulch plug, or chute).
  5. Start engine: Set throttle to FAST, pull starter cord firmly.
  6. Test drive: Engage drive control and test all 6 speeds.

CAUTION! Never add fuel while engine is hot. Allow engine to cool for 5 minutes.

Specifications

Controls and Operation

Main controls located on handle: Drive control, throttle, starter cord, height adjustment lever.

Starting Procedure: 1. Check oil and fuel. 2. Set throttle to FAST. 3. Pull starter cord firmly. 4. Allow engine to warm up 30 seconds.

Drive Control: Squeeze lever to engage self-propelled drive; release to stop. Adjust speed with 6-speed selector.

Height Adjustment: Move single lever to one of 6 positions (1.5-4 inches).

Stopping: Release drive control, move throttle to STOP, wait for blades to stop completely.

Cutting System Setup

Configure for mulching, bagging, or side discharge.

  1. Mulching: Install mulch plug in discharge opening. Ensure blade is mulching type.
  2. Bagging: Attach grass bag to support frame. Empty when bag is 2/3 full.
  3. Side Discharge: Install discharge chute. Direct clippings away from people and objects.

Tip: For best results, mow when grass is dry. Overlap passes by 2-3 inches.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

IntervalTask
Before each useCheck oil level, inspect blade, clear deck of debris
Every 25 hoursChange engine oil, clean air filter, check spark plug
Every 50 hoursReplace air filter, sharpen blade, check drive belt
Every 100 hoursReplace spark plug, clean fuel system, check wheels
Season endDrain fuel, change oil, clean thoroughly before storage

Blade Sharpening: Remove spark plug wire. Remove blade, sharpen at 30-degree angle, balance before reinstalling.

Storage Guidelines

Proper storage prevents fuel system issues and corrosion.

  1. Drain fuel tank or add fuel stabilizer.
  2. Run engine 5 minutes to circulate treated fuel.
  3. Change engine oil.
  4. Clean entire mower, especially under deck.
  5. Remove spark plug, add 1 oz. oil to cylinder, pull starter slowly.
  6. Store in dry, covered area.

CAUTION! Never store with fuel in tank untreated. Fuel deteriorates over time.

Safety Information

Always follow these safety precautions when operating.

DANGER! Rotating blade can cause serious injury. Always ensure blade has stopped before crossing gravel drives or roads.

Warranty Information

Ariens 915265 comes with a 3-year limited warranty for residential use. Warranty covers defects in materials and workmanship. Not covered: normal wear, improper maintenance, commercial use, or damage from accidents. Keep original receipt for warranty claims. For warranty service, contact authorized Ariens dealer or call 1-800-678-5443. Register product at www.ariens.com within 30 days of purchase.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startNo fuel, old fuel, spark plugAdd fresh fuel, check spark plug, ensure throttle on FAST
Engine runs poorlyDirty air filter, old fuelClean/replace air filter, drain old fuel
Uneven cuttingDull blade, uneven tire pressureSharpen blade, check tire pressure (12-15 PSI)
Self-propelled not workingDrive cable, belt, transmissionAdjust drive cable, check belt, test transmission
Excessive vibrationLoose blade, bent bladeTighten blade bolts, replace bent blade
Grass not dischargingWet grass, clogged deckWait for grass to dry, clean under deck

Service: For technical support, contact Ariens at 1-800-678-5443 or visit www.ariens.com.

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