Stihl Chainsaw Shop Manual

The Stihl Chainsaw Shop Manual is a comprehensive guide for the maintenance, repair, and operation of Stihl chainsaws. It covers safety procedures, technical specifications, troubleshooting, engine maintenance, fuel system, ignition system, cutting equipment, and routine service intervals. Below are key sections for safety, features, maintenance procedures, specifications, operation, and troubleshooting.

1. Features at a Glance 2. Safety Precautions 3. Technical Specifications 4. Maintenance Procedures 5. Engine System 6. Fuel System 7. Ignition System 8. Cutting Equipment 9. Troubleshooting 10. Service Intervals 11. Warranty Information

Features at a Glance

Key components: Engine assembly, guide bar, cutting chain, chain brake, throttle trigger, choke control, fuel tank, oil tank, spark plug, air filter, and muffler.

Feature	Description
Engine Type	2-stroke gasoline engine with electronic ignition
Guide Bar	Available in various lengths (e.g., 14", 16", 18")
Cutting Chain	Low-kickback chain with safety features
Chain Brake	Inertia-activated safety brake
Fuel Tank Capacity	Typically 0.5 - 1.0 liters depending on model
Oil Tank Capacity	Chain lubrication system with adjustable flow
Air Filter System	Pre-cleaner and main filter for engine protection
Anti-Vibration System	Reduces operator fatigue during extended use
Decompression Valve	Easier starting on larger engine models
Quick Chain Adjuster	Tool-free chain tension adjustment

Safety Precautions

Always wear proper protective equipment and follow safety guidelines.

Personal Protective Equipment: Wear safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toed boots.
Work Area Safety: Clear work area of obstacles; maintain secure footing.
Chain Brake: Test chain brake before each use.
Fuel Safety: Refuel in well-ventilated area with engine off and cool.

WARNING! Never operate chainsaw with damaged or missing safety features. Keep hands away from moving chain.

Technical Specifications

Engine Displacement: 30.1cc to 91.1cc depending on model.
Power Output: 1.5 kW to 6.4 kW.
Fuel Mix Ratio: 50:1 (Premium gasoline to STIHL HP Ultra oil).
Idle Speed: 2,500 - 3,000 rpm (adjustable).
Maximum Power Speed: 9,000 - 14,000 rpm.
Spark Plug: NGK BPMR7A or equivalent.
Ignition System: Electronic, capacitor discharge.
Weight: 3.0 kg to 7.5 kg (powerhead only).
Sound Pressure Level: Typically 105-115 dB(A).
Vibration Level: Front/rear handles: <2.5 m/s².

Maintenance Procedures

Regular maintenance ensures optimal performance and longevity.

Daily Checks: Inspect chain sharpness, tension, and lubrication.
Air Filter: Clean weekly; replace when damaged or excessively dirty.
Spark Plug: Check gap (0.5mm); clean or replace as needed.
Chain Sprocket: Inspect for wear; replace if worn.
Guide Bar: Clean groove; flip regularly for even wear.
Fuel Filter: Replace annually or when clogged.

CAUTION! Always disconnect spark plug wire before performing maintenance.

Engine System

Cylinder and piston assembly, crankshaft, bearings, and seals.

Compression Test: Should read 120-150 psi for proper engine health.

Carburetor Adjustment: LA (idle), H (high speed), L (low speed) screws. Initial settings: LA=1 turn out, H=1 turn out, L=1 turn out.

Muffler: Clean spark arrestor screen regularly to prevent overheating.

Fuel System

Fuel tank, filter, lines, carburetor, and primer bulb.

Fuel Mix: Always use fresh 89+ octane gasoline mixed with STIHL HP Ultra at 50:1 ratio.
Carburetor Cleaning: Disassemble and clean with compressed air; replace gaskets.
Fuel Lines: Inspect for cracks; replace if brittle or leaking.
Fuel Filter: Replace annually or when flow is restricted.

Tip: Use fuel stabilizer if storing chainsaw for more than 30 days.

Ignition System

Spark plug, ignition coil, flywheel, and stop switch.

Spark Plug: Gap to 0.5mm (0.020"); replace annually.
Ignition Coil: Air gap should be 0.2-0.4mm; adjust if necessary.
Flywheel: Check key for shearing; ensure tight mounting.
Stop Switch: Test for proper ground connection.

WARNING! Never check for spark with plug removed and wire near cylinder. Use spark tester.

Cutting Equipment

Guide bar, cutting chain, sprocket, and chain tensioner.

Chain Sharpening: File at 30° angle; maintain consistent depth gauge height.
Bar Maintenance: Clean oil holes; file rails if burred.
Sprocket Inspection: Replace if worn (teardrop shape indicates wear).
Chain Tension: Proper tension allows chain to snap back when lifted from bar.

CAUTION! Always wear gloves when handling chain. Chain is extremely sharp.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, fuel issues, flooded	Check spark plug, fuel mix, choke setting. Use cold start procedure.
Engine runs poorly	Dirty air filter, carb adjustment	Clean/replace air filter; adjust carburetor H and L screws.
Chain won't turn	Brake engaged, clutch issues	Disengage chain brake; inspect clutch springs and drum.
Excessive vibration	Loose components, unbalanced chain	Tighten all fasteners; balance chain or replace if damaged.
Chain doesn't oil	Clogged oil ports, pump failure	Clean oil passages; test oil pump output; replace if faulty.
Overheating	Dirty cooling fins, lean mixture	Clean cylinder fins; check carburetor adjustment and fuel mix.

Service Intervals

Recommended maintenance schedule for optimal performance.

Interval	Service Required
Daily	Check chain tension and sharpness; clean air filter
Weekly	Clean spark arrestor; inspect guide bar groove
Monthly	Check all fasteners; clean cooling fins
Annually	Replace spark plug, fuel filter; inspect clutch
Every 2 years	Replace fuel lines; inspect carburetor diaphragm

Warranty Information

STIHL Limited Warranty: 1 year commercial use, 2 years residential use from date of purchase. Warranty covers defects in materials and workmanship. Not covered: normal wear, misuse, improper maintenance, or use of non-STIHL parts. For warranty service, contact authorized STIHL dealer with proof of purchase. For technical support, visit www.stihlusa.com or contact 1-800-467-8445.