stihl ms 250 manual pdf

The STIHL MS 250 is a lightweight, professional-grade chainsaw designed for demanding cutting tasks. It features a powerful engine, advanced anti-vibration system, Quickstop® inertia chain brake, STIHL Ematic™ lubrication system, and easy-to-use controls. Below are key sections for safety, features, operation, maintenance, troubleshooting, and specifications.

1. Features at a Glance 2. Safety Information 3. Assembly & First Use 4. Specifications 5. Controls and Components 6. Starting the Engine 7. Operation & Cutting Techniques 8. Maintenance Schedule 9. Chain & Bar Care 10. Storage Guidelines 11. Troubleshooting

Features at a Glance

Key components: STIHL engine with decompression valve, Quickstop® inertia chain brake, side-access chain tensioner, STIHL Ematic™ lubrication system, anti-vibration handles.

Feature	Description
Engine Displacement	45.4 cc
Power Output	2.6 kW / 3.5 bhp
Guide Bar Lengths	16" or 18" (recommended)
Chain Pitch/Gauge	.325" / .063"
Weight (powerhead)	5.2 kg (11.5 lbs)
Fuel Tank Volume	410 ml (13.9 fl. oz)
Oil Tank Volume	200 ml (6.8 fl. oz)
Ignition System	Electronic, capacitor discharge
Anti-Vibration System	Advanced damping elements
Safety Features	Chain brake, throttle interlock, right-hand guard

Safety Information

Read and understand the manual before operation. Wear proper PPE: helmet, eye protection, hearing protection, gloves, chainsaw chaps, and sturdy boots.

Clear work area of obstacles and bystanders.
Inspect chainsaw before each use: chain sharpness, tension, and lubrication.
Always engage chain brake when starting or carrying the saw.
Use proper grip: left hand on front handle, right hand on rear handle.
Never operate above shoulder height or with one hand.

WARNING! Risk of kickback! Avoid contact with bar nose. Always hold saw firmly with both hands.

Assembly & First Use

Unpack and inspect contents. Assemble guide bar and chain.

Attach guide bar: Loosen nuts, position bar on studs, align chain drive links with sprocket.
Install chain: Place chain over bar, ensuring cutting edges face forward on top.
Tension chain: Use side-access adjuster until chain snaps back when lifted from bar.
Fill tanks: Use STIHL MotoMix® or 50:1 fuel/oil mix for fuel; STIHL chain oil for lubrication.
Prime: Press fuel pump bulb 5-10 times until fuel is visible.

CAUTION! Use only STIHL-approved oils and fuels. Improper mix can cause engine damage.

Specifications

Model: STIHL MS 250.
Engine Type: 2-stroke, single cylinder.
Displacement: 45.4 cc.
Powerhead Weight: 5.2 kg (11.5 lbs).
Fuel/Oil Ratio: 50:1 (STIHL 2-stroke oil).
Sound Pressure Level: 106 dB(A).
Vibration Levels: Front handle 4.5 m/s², rear handle 5.5 m/s².
Warranty: Limited 1-year consumer / 90-day commercial.

Controls and Components

Main components: Throttle trigger, throttle trigger interlock, stop switch, choke control, decompression valve, master control lever, chain brake handle, fuel and oil caps, side-access chain tensioner.

Master Control Lever: Combines choke, start, and run positions. Chain Brake: Manual engagement via front handle; inertia-activated by kickback. Decompression Valve: Reduces pulling force for easier starting.

Starting the Engine

Cold Start Procedure:

Engage chain brake by pushing handle forward.
Set master control lever to choke position (full down).
Press decompression valve (if equipped).
Pull starter handle sharply until engine fires (1-3 pulls).
Move master control to half-throttle position.
Pull starter again until engine starts.
Blip throttle to disengage fast idle.

Tip: For warm start, set master control to run position (horizontal).

Operation & Cutting Techniques

Basic Cutting:

Disengage chain brake by pulling handle toward you.
Hold saw firmly, position for cut.
Squeeze throttle trigger to desired RPM.
Let chain do the work; avoid forcing.
For felling: Use notch and backcut technique.
For limbing: Cut from top side of branch.
For bucking: Support logs; cut from top down.

WARNING! Beware of pinch points. Plan escape path when felling.

Maintenance Schedule

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

Chain & Bar Care

Sharpening: Use round file matching chain pitch (5.5mm for .325"). Maintain 30° cutting angle. Lubrication: Ensure oiler is working; adjust flow via screw if equipped. Bar maintenance: Clean groove weekly; flip bar monthly for even wear.

CAUTION! Always wear gloves when handling chain. Disconnect spark plug wire for safety.

Storage Guidelines

Long-term storage: Drain fuel tank and run engine dry. Remove chain, clean and oil it. Store in dry place. Short-term: Use fuel stabilizer if storing with fuel.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark/flooded	Check spark plug; set master control to half-throttle; pull 5-6 times without choke.
Engine runs then dies	Fuel filter/clogged vent	Replace fuel filter; clean tank vent.
Poor cutting performance	Dull chain/improper tension	Sharpen chain; adjust tension.
Chain doesn't oil	Empty oil tank/clogged port	Fill oil tank; clean oiler holes in bar.
Excessive vibration	Loose components/worn AV mounts	Tighten all bolts; inspect anti-vibration elements.

Service: For repairs, contact authorized STIHL servicing dealer.

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