Stihl 031 AV Manual

The Stihl 031 AV is a professional-grade gasoline-powered chainsaw featuring an anti-vibration (AV) system, automatic oiling, manual chain brake, and a reliable two-stroke engine. Designed for demanding forestry and woodcutting tasks, it requires proper operation, maintenance, and safety procedures. Below are key sections for safety, features, operation, maintenance, troubleshooting, and specifications.

Features at a Glance

Key components: Two-stroke engine with anti-vibration system, manual chain brake, automatic chain oiler, adjustable oil pump, decompression valve, and ergonomic handles.

Feature	Description
Anti-Vibration System (AV)	Reduces operator fatigue during extended use
Automatic Chain Oiler	Lubricates chain continuously during operation
Manual Chain Brake	Stops chain rotation for safety when engaged
Decompression Valve	Eases starting by reducing cylinder pressure
Adjustable Oil Pump	Controls oil flow rate for different cutting conditions
Ergonomic Handles	Front and rear handles with comfortable grip
Chain Tensioner	Side-mounted for easy chain adjustment
Spark Arrestor Muffler	Reduces fire risk and noise
Fuel Tank	Integrated with easy-fill cap
Oil Tank	Separate reservoir for chain lubrication

Safety Information

Read all instructions before operation. Wear proper PPE.

1. Personal Protective Equipment: Safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toe boots.
2. Work Area Safety: Clear debris, ensure secure footing, maintain safe distance from others.
3. Kickback Prevention: Hold saw firmly, avoid tip contact, use reduced-kickback chain.
4. Fuel Safety: Mix fuel outdoors, use approved containers, avoid sparks or flames.

WARNING! Chainsaws are dangerous; improper use can cause serious injury or death. Always engage chain brake when not cutting.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar: Loosen nuts, position bar on studs, align chain tensioning pin.
2. Install chain: Place chain over sprocket and bar, ensure cutting teeth face forward.
3. Tension chain: Adjust with side screw until chain snaps back when pulled from bar.
4. Fill tanks: Add mixed fuel (50:1 gasoline/oil) to fuel tank; fill oil tank with bar and chain oil.

CAUTION! Ensure chain is properly tensioned; loose chain can derail and cause injury.

Specifications

• Engine Type: Two-stroke, single cylinder.
• Displacement: 49.0 cc (3.0 cu in).
• Power Output: 2.5 kW (3.4 hp).
• Fuel Capacity: 0.55 L (18.6 fl oz).
• Oil Capacity: 0.26 L (8.8 fl oz).
• Guide Bar Lengths: 40 cm (16 in) to 50 cm (20 in).
• Chain Pitch: 3/8" or .325".
• Weight (without bar/chain): 5.9 kg (13.0 lbs).
• Ignition System: Electronic, flywheel magneto.
• Spark Plug: Bosch WSR6F or equivalent.

Controls and Components

Main controls located on top and sides of saw. Front Handle: Throttle trigger, throttle lockout, manual chain brake lever. Rear Handle: Master control lever (stop switch, choke, fast idle), decompression valve, fuel primer bulb (if equipped).

Operation Controls: Master control lever positions: STOP (0), RUN (I), CHOKE (for cold start). Throttle trigger with lockout prevents accidental activation. Chain brake lever engages brake when pushed forward.

Maintenance Points: Air filter cover, spark plug, chain tensioner, oil pump adjustment, muffler.

Starting & Operation

Starting procedure (cold engine):

1. Engage chain brake by pushing lever forward.
2. Set master control lever to CHOKE position.
3. Press decompression valve (if equipped).
4. Place saw on ground, hold rear handle with right foot, pull starter cord briskly until engine fires.
5. Move master control to RUN, pull starter again until engine starts.
6. Blip throttle to disengage fast idle.

Cutting Techniques: Use full throttle during cuts; let chain do the work. Avoid cutting with tip. For felling, use proper notch and back cut procedures.

Maintenance Schedule

Daily: Clean air filter, check chain tension, inspect bar for wear. Weekly: Clean spark arrestor screen, check spark plug gap, clean cooling fins. Monthly: Clean fuel filter, check fuel lines, inspect anti-vibration elements. As needed: Sharpen chain, replace worn sprocket, clean carburetor.

Fuel Mix: Use high-quality 2-stroke oil mixed at 50:1 ratio with unleaded gasoline (minimum 89 octane). Do not use automotive oil or ethanol blends above 10%.

Chain & Bar Care

Chain sharpening: Use round file matching chain pitch (typically 4.0mm or 4.8mm). Maintain 30° filing angle. File all cutters evenly. Bar maintenance: Clean bar groove regularly, flip bar monthly for even wear, dress bar rails with flat file when burred.

Chain Tension: Proper tension: Chain should snap back when pulled from bar but not bind. Re-tension when chain feels loose; always check when saw is cool.

Storage Guidelines

Long-term storage (over 30 days):

1. Drain fuel tank and run engine until it stops.
2. Remove chain, clean and soak in oil.
3. Clean entire saw, especially cooling fins and air filter.
4. Store in dry place, cover to prevent dust.

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

Warranty Information

Stihl 031 AV comes with limited warranty covering defects in materials and workmanship. Warranty period varies by region (typically 1 year for consumer use). Proof of purchase required. Does not cover normal wear, misuse, or improper maintenance. For warranty claims, contact authorized Stihl dealer. Keep this manual as proof of proper operation guidelines.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, fuel issues	Check spark plug, set master control to RUN, use fresh fuel mix.
Engine runs then dies	Clogged fuel filter, vent	Replace fuel filter, check tank vent.
Poor cutting performance	Dull chain, low chain speed	Sharpen chain, check throttle linkage, clean air filter.
Excessive vibration	Loose components, worn AV mounts	Tighten all bolts, inspect anti-vibration elements.
Chain not oiling	Empty oil tank, clogged oil passages	Fill oil tank, clean oil holes in bar, adjust oil pump.
Chain throws off bar	Loose chain, worn sprocket	Properly tension chain, replace worn drive sprocket.

Service: For repairs beyond basic maintenance, contact authorized Stihl service dealer. Use only genuine Stihl replacement parts.