STIHL MS 181 C Manual

The STIHL MS 181 C is a lightweight, easy-to-handle chainsaw designed for homeowners and occasional users. It features a powerful gasoline engine with STIHL's advanced engine technology for reduced emissions, an anti-vibration system, an inertia-activated chain brake for safety, a side-access chain tensioner for easy adjustment, and a tool-free fuel and oil cap design. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine with STIHL engine technology, anti-vibration system, QuickStop® inertia chain brake, side-access chain tensioner, Ematic™ lubrication system, and easy-to-use controls.

Feature	Description
Engine	STIHL 2-stroke gasoline engine with reduced emissions
Anti-Vibration System	Reduces operator fatigue during extended use
QuickStop® Inertia Chain Brake	Automatically stops chain in kickback situations
Side-Access Chain Tensioner	Allows easy chain adjustment without tools
Ematic™ Lubrication System	Efficient oil delivery to bar and chain
Fuel and Oil Caps	Tool-free design for easy refueling
Decompression Valve	Easier starting
Chain Catch	Prevents chain from hitting operator if it breaks
Throttle Interlock	Prevents accidental throttle activation
Master Control Lever	Combines choke, stop, and run controls

Safety Information

Read and understand all safety instructions before operation.

1. Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, gloves, chainsaw chaps/pants, and sturdy boots.
2. Work Area Safety: Clear area of bystanders, especially children. Ensure secure footing.
3. Kickback Awareness: Understand kickback causes; keep saw properly sharpened; use reduced-kickback chain.
4. Fuel Safety: Refuel outdoors, away from ignition sources. Use approved fuel/oil mix.

WARNING! Chainsaws are dangerous. Failure to follow safety rules can result in serious injury or death. Never operate when tired or under the influence.

Assembly & First Use

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar and chain: Place bar on studs, loop chain over sprocket and bar, adjust tension with side knob.
2. Fill fuel tank: Use fresh gasoline (min. 89 octane) mixed with STIHL 2-stroke oil at 50:1 ratio.
3. Fill oil tank: Use STIHL chainsaw bar and chain oil.
4. Start the engine: Place on ground, engage chain brake, set Master Control to choke, pull starter cord until engine fires, then set to run and pull again.

CAUTION! Ensure chain brake is engaged when starting. Keep hands away from chain.

Specifications

• Engine Displacement: 31.8 cc
• Power Output: 1.8 kW / 2.4 hp
• Fuel/Oil Mix Ratio: 50:1 (STIHL 2-stroke oil)
• Guide Bar Lengths: Typically 16" (40 cm) or 18" (45 cm)
• Chain Pitch/Gauge: 3/8" PMM / .050" (1.3 mm)
• Weight (without bar/chain): Approximately 4.4 kg (9.7 lbs)
• Sound Pressure Level: ~106 dB(A)
• Vibration Level: Front/Rear handle: ~4.5/3.5 m/s²
• Fuel Tank Capacity: 0.25 L (0.07 US gal)
• Oil Tank Capacity: 0.20 L (0.05 US gal)

Controls and Components

Front/Rear Handle: Throttle trigger, throttle interlock, Master Control Lever (choke/stop/run), chain brake lever, hand guard.

Right Side: Side-access chain tensioner, oil filler cap, muffler.

Left Side: Fuel filler cap, decompression valve (if equipped), starter grip.

Operation Controls: Master Control Lever (sets choke, run, stop), chain brake (engage/disengage), throttle trigger with interlock.

Operation

Starting, cutting techniques, and stopping procedures.

1. Starting (Cold): Engage chain brake. Set Master Control to choke. Pull starter cord until engine fires. Move lever to run position. Pull cord to start.
2. Starting (Warm): Set Master Control to run position. Pull cord.
3. Cutting: Use full throttle when cutting. Let chain do the work; don't force. Be aware of pinch points.
4. Stopping: Release throttle, allow engine to idle. Set Master Control to STOP position.

Tip: Practice cutting on small logs. Always plan your cut and escape path.

Maintenance

Regular maintenance ensures performance and longevity.

1. Daily: Clean air filter, check chain tension and sharpness, inspect for loose parts.
2. Weekly/Monthly: Clean cooling fins, check spark plug, clean fuel filter.
3. Fuel System: Use fresh fuel mix. Empty tank for long-term storage.
4. Spark Plug: Clean and regap (0.5 mm / 0.020") or replace as needed.

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

Chain & Bar Care

Proper chain maintenance is critical for safety and performance.

1. Sharpening: Use correct round file size (typically 4.0 mm). Maintain correct filing angle (30°). File all cutters evenly.
2. Tensioning: Chain should be snug against bar but pull freely by hand. Re-tension when warm.
3. Bar Maintenance: Clean bar groove regularly. Flip bar periodically for even wear.
4. Lubrication: Ensure oiler is working. Check oil output at full throttle against a light surface.

CAUTION! Always wear gloves when handling chain. A dull chain is dangerous and inefficient.

Storage

Prepare saw for storage to prevent fuel system issues.

1. Empty fuel tank and run engine until it stops to clear carburetor.
2. Remove chain and bar; clean and oil them.
3. Clean entire saw; store in dry place.
4. For long storage, remove spark plug and add a few drops of oil into cylinder; pull starter slowly to coat.

CAUTION! Store fuel mix in approved container away from living areas.

Warranty & Support

STIHL Limited Warranty: Covers defects in materials/workmanship for a specified period from date of retail purchase. Proof of purchase required. This warranty does not cover normal wear, misuse, or improper maintenance. For support, contact an authorized STIHL servicing dealer or visit www.stihlusa.com.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine will not start	No fuel, flooded, spark plug	Check fuel; set control to run and pull with throttle open; check/clean spark plug.
Engine runs but dies	Clogged fuel filter, air filter	Replace fuel filter; clean air filter.
Chain does not turn	Chain brake engaged, clutch, sprocket	Disengage chain brake; inspect clutch and sprocket for wear.
Chain oil not flowing	Empty oil tank, clogged oiler	Fill oil tank; clean oil passage and bar groove.
Excessive vibration	Loose parts, unbalanced chain	Tighten all fasteners; sharpen chain evenly.
Poor cutting performance	Dull chain, incorrect tension	Sharpen chain; adjust tension properly.

Service: For repairs beyond basic maintenance, take to an authorized STIHL dealer.

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