Stihl Chainsaw MS290 Manual

The Stihl MS290 Farm Boss is a professional-grade chainsaw designed for demanding cutting tasks. It features a powerful 56.5 cc engine, advanced anti-vibration system, Quickstop® inertia chain brake, Ematic™ lubrication system, and STIHL Easy2Start™ for simplified starting. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine, guide bar, saw chain, anti-vibration system, chain brake, oil and fuel tanks, throttle trigger, master control lever.

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. Work Area Safety: Clear area of bystanders, especially children. Ensure secure footing.
3. Kickback Zone: Avoid contact with the upper quarter of the guide bar tip.
4. Chain Brake Test: Test function before each use by engaging brake with saw off.
5. Fuel Safety: Refuel in well-ventilated area, engine off and cool. Use STIHL MotoMix® or 50:1 mix with high-quality oil.

WARNING! Kickback can cause severe injury or death. Always hold saw firmly with both hands.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar: Loosen nuts, position bar on studs, align chain drive links with sprocket.
2. Install chain: Place chain over bar, ensure cutting edges face forward on top.
3. Tension chain: Adjust tensioning screw until chain fits snug against bar (lift slightly in middle).
4. Fill tanks: Add fuel/oil mixture to fuel tank and bar & chain oil to oil tank.
5. Check controls: Ensure throttle trigger, throttle lockout, and master control lever function properly.

CAUTION! Wear protective gloves when handling chain. Chain is extremely sharp.

Specifications

• Model: MS 290 Farm Boss
• Engine Type: 2-stroke, single cylinder
• Displacement: 56.5 cc (3.45 cu. in.)
• Powerhead Weight: 13.2 lbs (6.0 kg) without bar and chain
• Fuel/Oil Ratio: 50:1 (STIHL HP Ultra or equivalent)
• Ignition System: Electronic, capacitor discharge
• Carburetor: Diaphragm type with fuel pump
• Starter: Rewind starter with Easy2Start™
• Chain Brake: Quickstop® inertia activated
• Warranty: Limited 1-year consumer / 90-day commercial

Controls and Components

Master Control Lever: Combines choke, throttle lock, and stop functions. Front Handle: Includes throttle trigger with lockout. Rear Handle: Contains start/stop switch.

Additional Controls: Chain brake lever (front handle), decompression valve (for easier starting), chain tensioning screw (side), oil filler cap, fuel filler cap.

Maintenance Points: Air filter cover, spark plug, muffler, clutch cover, chain catcher. Safety Features: Right-hand guard, chain brake, throttle lockout.

Starting & Stopping

Cold Start Procedure:

1. Engage chain brake by pushing forward on front hand guard.
2. Set master control lever to choke position (full down).
3. Press decompression valve (if equipped).
4. Place saw on firm ground, hold rear handle with right foot.
5. Pull starter rope slowly until resistance is felt, then pull briskly.
6. After engine fires, move master control lever to half-throttle position.
7. Pull starter rope again to start. Allow to warm up at idle.
8. Disengage chain brake by pulling back on hand guard.

Warm Start: Master control lever in run position (horizontal).

Stopping: Release throttle, move master control lever up to STOP position.

Operating Instructions

Proper cutting techniques for safety and efficiency.

1. Basic Stance: Feet shoulder-width apart, left foot slightly forward.
2. Grip: Left hand on front handle, thumb wrapped underneath. Right hand on rear handle.
3. Starting Cut: Apply slight throttle, let chain touch wood gently.
4. Kickback Prevention: Never cut with tip. Be aware of tension in wood.
5. Bucking: Cut from top down. For large logs, cut from top, then finish from bottom.
6. Limbing: Stand on opposite side of tree. Cut limbs from bottom to top.
7. Felling: Notch cut first (1/3 diameter), then back cut. Use wedges if needed.

Tip: Let the chain do the work; don't force the saw.

Maintenance Schedule

CAUTION! Always disconnect spark plug wire before performing maintenance.

Chain Sharpening & Tensioning

Proper chain maintenance is critical for performance and safety.

1. Sharpening: Use round file matching chain pitch (.325"). Maintain 30° filing angle. File all cutters to equal length.
2. Depth Gauges: Use flat file and depth gauge tool to maintain proper height (0.025" below cutter).
3. Tensioning: Loosen bar nuts. Turn tensioning screw clockwise until chain is snug. Chain should pull freely around bar. Retighten nuts.
4. Lubrication: Always use STIHL or approved bar & chain oil. Check oil flow by running saw over light surface; look for oil line.

WARNING! A dull chain increases kickback risk and operator fatigue.

Storage Guidelines

For storage longer than 30 days:

1. Drain fuel tank and run engine until it stops.
2. Remove spark plug, add 1 teaspoon of oil through spark plug hole. Pull starter rope slowly to distribute oil, then reinstall plug.
3. Clean entire saw, especially cooling fins and air filter.
4. Remove chain, clean and soak in oil. Store separately.
5. Store in dry, secure location, out of reach of children.

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

Troubleshooting

Service: For repairs beyond basic maintenance, contact an authorized STIHL servicing dealer.

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