STIHL Chainsaw MS260 Manual

The STIHL MS260 is a professional-grade gasoline chainsaw designed for demanding forestry, arboriculture, and general cutting tasks. It features a powerful engine with STIHL's advanced engine management, anti-vibration system, quickstop chain brake, side-access chain tensioner, and tool-free fuel and oil caps. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine with decompression valve, Quickstop Plus inertia-activated chain brake, Ematic lubrication system, side-mounted chain tensioner, anti-vibration system, and muffler with spark arrestor.

Safety Information

Read and understand all safety warnings before operation.

1. Personal Protective Equipment (PPE): Always wear chainsaw chaps, safety glasses, hearing protection, gloves, and steel-toe boots.
2. Operating Area: Keep bystanders and pets at least 15 feet away. Be aware of falling branches.
3. Fuel Safety: Refuel in well-ventilated area, engine off and cool. Use STIHL MotoMix or 89+ octane gasoline with STIHL HP Ultra oil at 50:1 ratio.
4. Kickback Zone: Avoid contact with upper quadrant of guide bar tip. Always grip saw firmly with both hands.
5. Chain Brake Test: Test function before each use by pushing front hand guard forward.

WARNING! Failure to follow safety instructions can result in serious injury or death. Never operate a chainsaw while fatigued or under the influence.

Assembly & First Use

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar: Remove side cover, place bar over studs, ensure chain is correctly oriented (cutting teeth facing forward on top).
2. Install chain: Loop chain over sprocket and onto bar groove. Adjust tension via side screw.
3. Fill fluids: Add fuel/oil mix to fuel tank. Fill bar and chain oil tank with STIHL chain oil.
4. Start engine: Place on firm ground, engage chain brake, set master control lever to cold start position, pull starter rope until engine fires.

CAUTION! Ensure chain brake is engaged when starting. Keep saw on ground, never drop-start.

Specifications

• Model: STIHL MS 260
• Engine Type: 2-stroke, single cylinder
• Displacement: 50.2 cm³ (3.06 cu. in.)
• Powerhead Weight: 10.8 lbs (4.9 kg)
• Fuel/Oil Ratio: 50:1 (STIHL HP Ultra)
• Idle Speed: 2,800 RPM
• Maximum Power Speed: 13,000 RPM
• Sound Pressure Level: 106 dB(A)
• Vibration Levels (front/rear): 4.2/2.5 m/s²
• Warranty: Limited 1-year commercial, 2-year residential

Controls and Components

Master Control Lever: Combines stop switch, choke, and run positions. Throttle Trigger: With interlock. Throttle Trigger Lockout: Must be depressed to engage throttle. Chain Brake/Hand Guard: Inertia-activated. Decompression Valve: Eases starting. Fuel/Oil Caps: Tool-free. Chain Tensioner: Side-access screw.

Maintenance Points: Air filter, spark plug (BPMR 7A), fuel filter, chain catcher, muffler.

Operation

Starting, cutting techniques, and shutdown.

1. Cold Start: Set master control to choke (full down), press decompression valve, pull starter 2-3 times until engine 'pops'. Move lever to half-throttle position, pull until starts. Blip throttle to disengage fast idle.
2. Warm Start: Master control to run position, pull starter.
3. Cutting: Use full throttle when cutting. Let chain do the work. For felling, use proper notch and back cut techniques.
4. Shutdown: Allow to idle briefly, move master control to STOP position.

Tip: Maintain sharp chain and proper tension for efficient cutting and reduced operator fatigue.

Maintenance Schedule

Daily/Before Use: Check chain tension, sharpness, brake function, fluid levels. Clean air filter. Weekly: Clean cooling fins, check spark plug. Monthly: Clean fuel filter, check all nuts/bolts for tightness. Annually: Have carburetor adjustment and compression check performed by authorized STIHL dealer.

WARNING! Always disconnect spark plug wire before performing maintenance other than chain tensioning.

Chain Sharpening & Tensioning

Proper chain maintenance is critical for safety and performance.

1. Tensioning: Loosen bar nuts. Turn tensioning screw clockwise until chain fits snug against bar but can be pulled around by hand. Retighten bar nuts.
2. Sharpening: Use round file matching chain pitch (typically 3/8" LP). File each cutter at 30° angle, maintaining equal length on all cutters. File depth gauges with flat file.

CAUTION! Wear gloves when handling chain. A loose chain can derail; an overtightened chain can break.

Storage

For storage over 30 days: Drain fuel tank and run engine until it stops. Remove spark plug, add 1 teaspoon of engine oil through spark plug hole, pull starter slowly 2-3 times to coat cylinder. Reinstall plug. Clean entire saw, lightly oil bar and chain. Store in dry, secure location.

CAUTION! Never store with fuel in tank for extended periods; fuel can degrade and damage carburetor.

Warranty & Support

STIHL Limited Warranty: 1 year for commercial use, 2 years for non-commercial use. Proof of purchase required. Warranty does not cover normal wear, misuse, or improper maintenance. For genuine parts and service, see an authorized STIHL dealer. For support, visit www.stihlusa.com or contact STIHL Incorporated at 1-800-467-8445.

Troubleshooting

Dealer Service: For carburetor adjustment, internal engine repairs, or electrical issues, contact authorized STIHL dealer.

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