Stihl MS270C Manual

The Stihl MS270C is a professional-grade chainsaw featuring a powerful engine, advanced anti-vibration system, Quickstop® inertia chain brake, STIHL Ematic™ lubrication system, and easy-to-use controls. Designed for demanding cutting tasks, it offers reliable performance, enhanced safety features, and low emissions. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine with STIHL 2-MIX technology, Anti-Vibration System, Quickstop® Inertia Chain Brake, Side-access chain tensioner, STIHL Ematic™ lubrication system, and decompression valve.

Feature	Description
Engine Type	STIHL 2-MIX engine for reduced fuel consumption and emissions
Displacement	50.2 cc
Power Output	3.0 bhp (2.2 kW)
Fuel Tank Capacity	500 ml (16.9 fl. oz.)
Oil Tank Capacity	260 ml (8.8 fl. oz.)
Guide Bar Lengths	16" (40 cm) or 18" (45 cm) recommended
Chain Pitch/Gauge	.325" pitch, .063" gauge (standard)
Weight (powerhead)	5.7 kg (12.6 lbs)
Ignition System	Electronic ignition (CDI)
Safety Features	Quickstop® chain brake, front hand guard, throttle lockout

Assembly & Preparation

Unpack and inspect all components. Ensure all parts are present and undamaged.

1. Attach guide bar and chain: Place bar on studs, fit chain with cutters facing forward, tighten bar nuts hand-tight.
2. Adjust chain tension: Use side-access tensioner to set proper tension (slight sag on bottom).
3. Fill fuel tank: Use STIHL MotoMix® or 50:1 gasoline/oil mixture (STIHL HP Ultra oil).
4. Fill oil tank: Use STIHL chain oil or equivalent.
5. Check controls: Ensure throttle trigger, throttle lockout, and chain brake function properly.

WARNING! Always wear protective gear: helmet, goggles, gloves, chainsaw chaps, and hearing protection.

First-Time Operation

Before starting, review all safety instructions in manual.

1. Place on clear, level ground: Engage chain brake.
2. Set master control lever: Move to cold start position (choke).
3. Prime fuel system: Press fuel pump bulb 5-10 times.
4. Start engine: Hold front handle with left hand, place right foot in rear handle. Pull starter rope briskly until engine fires.
5. Disengage choke: Move master control to run position after engine starts.
6. Warm up: Allow engine to idle for 30 seconds before cutting.
7. Test chain brake: With engine at idle, push front hand guard forward to engage brake.

CAUTION! Never drop-start or start above waist height. Keep bystanders at least 15 feet away.

Specifications

• Engine: STIHL 2-MIX, single cylinder, air-cooled.
• Displacement: 50.2 cc.
• Power Output: 3.0 bhp (2.2 kW) at 9,000 rpm.
• Idle Speed: 2,800 rpm.
• Maximum Powerhead Speed: 13,500 rpm.
• Fuel/Oil Ratio: 50:1 (STIHL MotoMix® recommended).
• Sound Pressure Level: 106 dB(A).
• Vibration Levels: Left/Right 3.2 m/s², Front/Rear 2.8 m/s².
• Emissions: Meets EPA Phase II and CARB regulations.
• Warranty: Limited warranty for personal/commercial use.

Controls and Functions

Master Control Lever: Combines stop switch, choke, and run positions. Throttle Trigger: Controls engine speed. Throttle Lockout: Must be depressed to operate throttle. Chain Brake Lever: Manual engagement; inertia-activated. Decompression Valve: Reduces pulling resistance during starting. Side-Access Chain Tensioner: For easy chain adjustment. Fuel/Oil Caps: Quarter-turn design with retaining chains.

Starting Procedure: Engage chain brake → Set master control to cold start → Prime → Pull starter rope → Disengage choke after engine fires.

Chain & Bar Setup

Proper chain tension is critical for safety and performance.

1. Loosen bar nuts: Use combination wrench.
2. Adjust tension: Turn tensioning screw clockwise to tighten until chain fits snug against bar.
3. Check tension: Pull chain around bar – should move freely with slight sag on bottom.
4. Retighten bar nuts: Tighten while lifting bar tip upward.
5. Final check: Chain should not bind when pulled manually.

Tip: Always check chain tension when cold and after brief use when warm.

Safe Operation Procedures

Supports felling, limbing, bucking, and pruning when used properly.

1. Personal Protective Equipment: Always wear full safety gear.
2. Clear work area: Remove tripping hazards, ensure escape path.
3. Secure workpiece: Never cut with tip or one-handed.
4. Proper stance: Feet shoulder-width apart, firm grip with both hands.
5. Kickback prevention: Maintain firm grip, avoid contact with bar tip.
6. Cutting techniques: Let saw do the work, avoid forcing.
7. Shut down: Engage chain brake, move master control to stop after use.

WARNING! Kickback zone is upper quadrant of bar tip. Never operate with damaged or loose chain.

Maintenance Schedule

Daily: Clean air filter, check chain tension and sharpness, inspect bar for wear. Weekly: Clean cooling fins, check spark plug, clean fuel filter. Monthly: Clean spark arrestor screen, check anti-vibration elements, inspect clutch and sprocket. As needed: Replace worn chain, bar, or sprocket.

Storage & Transport

For storage over 30 days: Drain fuel tank, run engine until it stops. Remove chain, clean and oil bar/chain. Store in dry place with bar cover installed.

CAUTION! Always transport with chain brake engaged and bar cover installed. Secure in vehicle to prevent movement.

Regulatory Information

EPA Certified: Meets emission standards for handheld engines. CARB Compliant: For sale and use in California. Safety Standards: Complies with ANSI B175.1 and applicable OSHA regulations. Copyright © STIHL Incorporated. All rights reserved. For support, visit www.stihlusa.com or contact 1-800-467-8445.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Fuel, spark, or air	Check fuel mixture, spark plug, air filter. Prime fuel system.
Engine runs poorly	Clogged filter or carburetor	Clean/replace air and fuel filters. Check fuel lines.
Chain doesn't turn	Brake engaged or clutch	Disengage chain brake. Check clutch springs and drum.
Excessive vibration	Loose components or AV mounts	Tighten all fasteners. Check anti-vibration elements.
Chain oil not flowing	Clogged oiler or wrong oil	Clean oil passages. Use proper chain oil. Check pump.
Chain dulls quickly	Dirt or improper filing	Clean bar groove. Sharpen with proper file and gauge.

Service: For repairs, use STIHL-approved dealers only. 1-800-467-8445; www.stihlusa.com