Stihl MS 341 Manual

The Stihl MS 341 is a professional-grade chainsaw featuring a powerful engine, advanced anti-vibration system, quick chain adjustment, and enhanced safety features. Designed for demanding forestry and tree service work, it offers reliable performance, easy maintenance, and ergonomic operation. Below are key sections for safety, features, operation, maintenance, troubleshooting, and specifications.

Features at a Glance

Key components: High-performance engine with decompression valve, STIHL Quickstop® inertia chain brake, ElastoStart handle, anti-vibration system, side-access chain tensioner, and tool-free air filter cover.

Feature	Description
Engine Displacement	64.1 cc two-stroke engine
Power Output	4.4 bhp for high cutting performance
Fuel System	STIHL HD2 carburetor with manual choke
Ignition System	Electronic ignition (CDI)
Chain Brake	STIHL Quickstop® inertia-activated safety feature
Anti-Vibration	Advanced damping system in front and rear handles
Starting System	ElastoStart for reduced pulling effort
Chain Tensioning	Side-access adjustment without tools
Air Filtration	Pre-separation and heavy-duty filter system
Weight (powerhead)	Approx. 6.8 kg (15.0 lbs)

Safety Information

Read all instructions before operation. Wear proper PPE.

1. Personal Protective Equipment: Wear safety helmet, goggles, hearing protection, gloves, chainsaw chaps, and steel-toe boots.
2. Work Area Safety: Clear area of bystanders, ensure secure footing, and plan escape path from falling trees.
3. Chainsaw Handling: Hold firmly with both hands, right hand on rear handle, left on front. Do not operate above shoulder height.
4. Kickback Awareness: Keep chain sharp, avoid contact with tip, and engage chain brake when not cutting.

WARNING! Improper use can cause serious injury or death. Always follow safety procedures.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach Guide Bar: Remove bar cover nuts, fit bar onto studs, align chain with sprocket, and tension appropriately.
2. Install Chain: Place chain over bar with cutters facing forward, engage drive links in sprocket, and adjust tension.
3. Fill Fluids: Add STIHL HP Ultra 2-stroke oil to fuel mix (50:1 ratio). Fill bar and chain oil reservoir with STIHL chain oil.
4. Check Controls: Verify throttle trigger, throttle lockout, chain brake, and master control lever function.

CAUTION! Ensure chain is properly tensioned—snug against bar but pullable by hand.

Technical Specifications

• Engine Type: Single-cylinder two-stroke air-cooled.
• Displacement: 64.1 cc.
• Power Output: 4.4 bhp at 9,500 rpm.
• Fuel/Oil Ratio: 50:1 (STIHL HP Ultra oil).
• Fuel Tank Capacity: 0.81 L (0.21 US gal).
• Oil Tank Capacity: 0.36 L (0.095 US gal).
• Guide Bar Lengths: 16" to 24" (recommended).
• Chain Pitch/Gauge: 3/8" or .325"; 0.063" gauge.
• Sound Pressure Level: Approx. 112 dB(A).
• Vibration Levels: Front handle: 4.5 m/s²; Rear handle: 5.5 m/s².

Controls and Components

Master Control Lever: Combines choke, throttle lock, and stop functions. Front Handle: Includes hand guard and chain brake. Rear Handle: Contains throttle trigger, throttle lockout, and decompression valve button.

Key Controls: Master control (stop/run/choke), throttle trigger, throttle lockout, chain brake lever, decompression valve, primer bulb (if equipped).

Maintenance Points: Air filter cover, spark plug, chain tensioner, fuel and oil caps, muffler. Safety: Chain brake must be tested before each use. Anti-vibration: Rubber dampers isolate handles from engine.

Starting & Operation

Cold Start Procedure: Engage chain brake. Set master control to choke. Press decompression valve. Pull starter rope until engine fires. Move master control to run. Pull again to start.

1. Warm Start: Master control in run position; no choke needed.
2. Acceleration: Squeeze throttle trigger after starting; ensure chain does not rotate at idle.
3. Cutting Techniques: Use lower quadrant of bar for bucking; maintain steady throttle; avoid pinching.
4. Shutdown: Move master control to stop; engage chain brake.

Tip: Always start on ground or firmly held between knees with brake engaged.

Maintenance Schedule

Daily/Before Use: Check chain tension, sharpness, and lubrication; inspect air filter; verify all controls.

1. Every 10 Hours: Clean air filter; check spark plug; clean cooling fins.
2. Every 20 Hours: Clean spark arrestor screen (if equipped); inspect fuel filter.
3. Every 50 Hours: Replace spark plug; clean carburetor air intake; check anti-vibration elements.
4. Seasonal: Replace fuel filter; inspect bar for wear; service clutch and sprocket.

WARNING! Perform maintenance only when saw is cool and spark plug disconnected.

Chain & Bar Care

Sharpening: Use round file matching chain pitch (typically 5.5 mm). Maintain 30° filing angle; equalize cutters.

Chain Tension: Adjust when cool; chain should snap back when pulled from bar. Retighten after initial use.

Bar Maintenance: Clean bar groove weekly; flip bar monthly for even wear; dress rails with flat file if burred.

CAUTION! Always wear gloves when handling chain. Ensure chain brake engaged during adjustments.

Fuel & Lubrication

Fuel Mix: Use 89+ octane gasoline with STIHL HP Ultra 2-stroke oil at 50:1 ratio. Shake well before fueling.

Bar & Chain Oil: Use STIHL chain oil or equivalent for temperature conditions. Check oiler flow regularly.

Storage: Empty fuel tank for long storage; run carburetor dry. Use fuel stabilizer if storing up to 3 months.

Storage Guidelines

Long-term Storage: Clean entire saw; remove chain and bar; store in dry place. Protect from dust and moisture.

CAUTION! Fuel left in tank can degrade and damage carburetor. Always use fresh fuel mix.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Fuel old, spark plug fouled, choke setting	Use fresh fuel mix; clean/replace spark plug; check choke operation.
Engine runs poorly	Clogged air filter, carburetor adjustment	Clean air filter; adjust carburetor (H/L screws) per manual.
Chain doesn't turn	Clutch worn, sprocket damaged, brake engaged	Inspect clutch and sprocket; disengage chain brake.
Excessive vibration	Loose components, worn anti-vibration mounts	Tighten all fasteners; replace rubber dampers.
Chain not oiling	Clogged oiler, empty tank, wrong oil	Clean oil ports; fill with proper oil; check oil pump.

Service: For repairs, contact authorized STIHL servicing dealer. Use only STIHL replacement parts.

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