Manual for Stihl MS260 Chainsaw

The Stihl MS260 is a professional-grade, mid-range chainsaw designed for demanding forestry, arboriculture, and landscaping work. It features a powerful engine with advanced anti-vibration system, QuickStop® inertia chain brake, STIHL Ematic™ lubrication system, and a decompression valve for easier starting. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine with decompression valve, Anti-Vibration System, QuickStop® Chain Brake, Side-access chain tensioner, STIHL Ematic™ chain lubrication system, and fuel/oil caps with retaining straps.

Assembly & Preparation

Unpack and inspect all components. Assemble on a clean, stable surface.

1. Attach Guide Bar and Chain: Place bar on sprocket, fit chain with drive links in bar groove, tension correctly.
2. Fill Fuel Tank: Use fresh, high-quality 2-stroke engine oil mixed with unleaded gasoline (50:1 ratio for STIHL oil).
3. Fill Chain Oil Tank: Use STIHL chain oil or equivalent for proper lubrication.
4. Check All Fasteners: Ensure all nuts, bolts, and screws are tight before operation.

WARNING! Chainsaw is a dangerous tool; always wear proper PPE (helmet, gloves, eye/ear protection, chainsaw chaps, and boots).

First-Time Operation

Before starting, review all safety instructions in the manual.

1. Starting Procedure: Set master control lever to cold start position (choke), press decompression valve, pull starter handle until engine fires, then move lever to warm start/idle position.
2. Warm-up: Allow engine to idle for 30-60 seconds before applying load.
3. Chain Brake Test: Verify QuickStop® function by engaging brake before each use.
4. Chain Lubrication Check: Verify oil is reaching the chain by running saw briefly over light-colored surface.

CAUTION! Never drop-start the chainsaw. Always maintain firm footing and secure grip.

Specifications

• Engine Type: Single-cylinder, 2-stroke, air-cooled.
• Displacement: 50.2 cc.
• Power Output: 3.0 bhp at 9,500 rpm.
• Fuel/Oil Mix Ratio: 50:1 (with STIHL 2-stroke oil).
• Fuel Tank Capacity: 0.55 liters.
• Chain Oil Tank Capacity: 0.26 liters.
• Idle Speed: 2,800 rpm.
• Maximum Powerhead Speed: 13,500 rpm.
• Sound Pressure Level: Typically 106 dB(A).
• Vibration Levels: Front handle: 4.5 m/s², Rear handle: 5.5 m/s².

Controls and Functions

Master Control Lever: Combines stop switch, choke, and run positions. Throttle Trigger Lockout: Must be depressed to access throttle. Chain Brake Lever: Front hand guard activates QuickStop®. Decompression Valve: Reduces cylinder pressure for easier starting. Side-access Chain Tensioner: Allows adjustment without tools in some models.

Operation Sequence: Engage throttle lockout > Squeeze throttle trigger > Apply cutting pressure. Always release throttle trigger immediately after cut.

Chain & Bar Setup

Compatible with .325" pitch, 1.6 mm gauge chains. Guide bar lengths: 16" or 18".

1. Chain Installation: Ensure correct orientation (cutting edges face forward on top of bar).
2. Tension Adjustment: Chain should be snug against bar but pull freely by hand.
3. Bar Maintenance: Clean bar groove regularly, flip bar periodically for even wear.
4. Sprocket Inspection: Check drive sprocket for wear and replace if necessary.

Tip: A properly tensioned chain will not sag from the bar but can be rotated by hand.

Safe Operation Procedures

Always follow professional safety protocols.

1. Personal Protective Equipment: Wear all required PPE without exception.
2. Pre-Operation Inspection: Check chain sharpness, tension, all fasteners, and fuel/oil levels.
3. Cutting Techniques: Use appropriate techniques for felling, limbing, and bucking. Avoid kickback zone.
4. Two-Handed Operation: Always maintain secure grip with both hands.
5. Shut Down Procedure: Engage chain brake, allow to idle briefly, move master control to stop position.

WARNING! Never operate chainsaw above shoulder height or with one hand. Be aware of kickback danger.

Maintenance Schedule

Daily: Clean air filter, check chain sharpness/tension, inspect for loose fasteners. Weekly: Clean cooling fins, check spark plug, clean fuel filter. Monthly: Clean carburetor area, check anti-vibration elements, inspect clutch and sprocket. Seasonal: Replace fuel filter, spark plug, and clean exhaust system.

Storage Guidelines

For storage over 30 days: Drain fuel tank completely or add fuel stabilizer. Run engine until carburetor is dry. Remove chain, clean and oil it. Store in dry, secure location away from children.

CAUTION! Never store chainsaw with fuel in tank for extended periods without stabilizer.

Regulatory Information

EPA Phase II compliant for emissions. Meets ANSI B175.1 safety standards. Manufactured by STIHL Incorporated. All safety decals must remain legible and intact. For genuine STIHL parts and service, contact authorized STIHL dealers only. Customer support: 1-800-467-8445 or www.stihlusa.com.

Troubleshooting

Service Note: Major repairs and carburetor adjustments should be performed by authorized STIHL service dealers only.

Support: 1-800-467-8445; www.stihlusa.com