STIHL 009L Service Manual PDF

The STIHL 009L is a professional-grade gasoline-powered chainsaw designed for demanding forestry and arborist work. This service manual provides comprehensive technical information for maintenance, troubleshooting, and repair. It covers the engine, fuel system, ignition, cutting equipment, safety systems, and electrical components. Below are key sections for specifications, maintenance procedures, troubleshooting, and parts identification.

Specifications & Technical Data

Key technical parameters for the STIHL 009L chainsaw.

Feature	Specification
Engine Type	Single-cylinder, two-stroke, air-cooled gasoline engine
Displacement	45.4 cm³ (2.77 cu. in.)
Power Output	2.2 kW (3.0 hp)
Fuel/Oil Mix Ratio	50:1 (STIHL HP Ultra or equivalent)
Fuel Tank Capacity	0.55 L (18.6 fl. oz.)
Oil Tank Capacity	0.26 L (8.8 fl. oz.)
Guide Bar Lengths (Recommended)	35 cm (14"), 40 cm (16")
Chain Pitch/Gauge	3/8" PM / .050" (1.3 mm)
Ignition System	Electronic, breakerless
Weight (Powerhead, excl. cutting equipment)	5.2 kg (11.5 lbs)
Sound Pressure Level (LpA)	106 dB(A)
Vibration Level (ah, K)	5.5 m/s²

Safety Information & Symbols

Critical safety warnings and explanation of symbols found on the saw and in the manual.

1. Personal Protective Equipment (PPE): Always wear chainsaw protective pants, gloves, helmet with face screen and hearing protection, and sturdy boots.
2. Worksite Safety: Clear work area of obstacles. Maintain secure footing. Be aware of kickback zone.
3. Chain Brake: Understand function and testing procedure. Test before each use.
4. Fuel Safety: Refuel in well-ventilated area, with engine off and cool. Wipe off spills. Use approved fuel containers.
5. Symbols: Explanation of pictorial warnings for kickback, hearing protection, electrical hazard, etc.

WARNING! Failure to follow safety instructions can result in serious injury or death. The chain brake is not a substitute for safe working practices.

Maintenance Schedule

Recommended service intervals for daily, weekly, and periodic maintenance.

1. Before Each Use: Check chain tension, sharpness, and lubrication. Check all nuts and bolts for tightness. Test chain brake function. Check for fuel/oil leaks.
2. Daily (or after refueling): Clean air filter. Check fuel filter in tank.
3. Weekly (or every 10 operating hours): Clean cooling fins and cylinder area. Clean spark arrestor screen in muffler (if equipped).
4. Monthly (or every 20-50 operating hours): Clean spark plug, check electrode gap (0.5 mm / 0.020"). Inspect fuel lines and impulse line for cracks. Clean carburetor air intake passage.
5. Annually (or every 100 operating hours): Replace fuel filter. Check clutch drum and sprocket for wear. Inspect anti-vibration elements. Check ignition system (spark gap test).

CAUTION! Perform maintenance only when the saw is switched off and the spark plug boot is disconnected.

Engine System

• Cylinder & Piston: Inspection for scoring, carbon deposits, and ring wear. Piston ring end gap specification.
• Crankshaft & Bearings: Checking crankshaft runout and main bearing play. Seal replacement procedure.
• Muffler: Removal, cleaning of carbon deposits, and spark arrestor maintenance.
• Cooling System: Cleaning of cylinder fins, fan wheel, and air intake.
• Decompression Valve: Operation check and seal replacement.
• Compression Test: Procedure and acceptable pressure range (typically 110-140 psi).

Fuel System & Carburetor

Components: Fuel tank, lines, filter, primer bulb, and carburetor (typically Walbro or Zama).

Carburetor Adjustment: Idle speed (L) and high-speed (H) screw settings. Procedure for final adjustment under load. Importance of using a tachometer.

Fuel Line Replacement: Step-by-step guide for replacing suction and return lines. Impulse line inspection.

Fuel Filter: Location in tank and replacement procedure.

Diaphragm & Gasket Kit: Carburetor overhaul instructions, including diaphragm, gasket, and needle valve replacement.

Ignition System

Electronic ignition module, spark plug, and stop switch.

1. Spark Plug: Type (e.g., BOSCH WSR6F or equivalent), gap setting (0.5 mm).
2. Ignition Module Test: Checking for spark using a spark tester. Air gap adjustment between module and flywheel.
3. Flywheel: Removal using a puller. Keyway inspection.
4. Stop Switch Circuit: Continuity test to ensure engine grounds when switched off.

Tip: Always disconnect the spark plug boot before performing any work on the ignition system or engine.

Cutting Equipment & Bar/Chain

Supports guide bars up to 40 cm (16").

1. Chain Tensioning: Loosen bar nuts, adjust tensioning screw, retighten nuts. Check for proper sag on bottom of bar.
2. Bar Maintenance: Cleaning bar groove, flipping bar regularly for even wear. Checking for burrs and straightness.
3. Chain Sharpening: Correct filing angle (typically 30°), depth gauge (raker) setting. Use of filing gauge.
4. Sprocket: Inspection of drive sprocket (rim or spur type) for wear. Replacement procedure.
5. Chain Brake Assembly: Band inspection, mechanism cleaning, and function test.

WARNING! Always use STIHL recommended guide bars, chains, and sprockets matched to the pitch and gauge. A dull or improperly tensioned chain increases kickback risk.

Clutch & Drive System

Centrifugal clutch, drum, and drive shaft.

Component	Inspection & Service
Clutch Shoes	Check for wear, cracking, or glazing. Replace as a set.
Clutch Springs	Check for stretching or breakage.
Clutch Drum Bearing	Check for smooth rotation and play. Replacement procedure.
Drive Sprocket	Inspect for hooking or wear. Replace when worn.
Oil Pump	Manual or automatic type. Check output and adjust if applicable.

Electrical System

Limited to ignition and stop switch. (Note: 009L typically has no external lighting coil).

Stop Switch: Testing continuity between switch wire and ground when activated.

Wiring Harness: Visual inspection for cracks, chafing, or disconnected terminals.

Disassembly & Assembly

General sequence for major service.

1. Remove cutting equipment, clutch cover, and bar/chain.
2. Remove top cover, air filter cover, and carburetor cover.
3. Disconnect fuel lines and remove carburetor.
4. Remove starter assembly and fan cover.
5. Remove cylinder cover and muffler.
6. Remove cylinder base nuts and separate cylinder from crankcase.
7. Remove piston pin circlips and pin to separate piston from connecting rod.
8. Reverse sequence for assembly using new gaskets and seals. Torque fasteners to specification.

CAUTION! Use proper tools (piston pin tool, flywheel puller, torque wrench). Mark components for reassembly alignment.

Troubleshooting & Diagnostics

Symptom	Possible Cause	Corrective Action
Engine will not start	No spark, flooded, fuel issue, compression	Check spark, plug condition. Dry plug if flooded. Check fuel lines, filter, carburetor. Test compression.
Engine starts but dies	Clogged fuel filter, carburetor adjustment, air leak	Replace fuel filter. Adjust carburetor L/H screws. Check crankcase seals and intake boot for leaks.
Lacks power under load	Clogged air filter, spark arrestor, carburetor, exhaust port carbon	Clean/replace air filter. Clean spark arrestor. Adjust/repair carburetor. Decarbonize muffler and exhaust port.
Chain does not stop when brake is applied	Worn brake band, dirty mechanism, broken spring	Inspect brake band and mechanism. Clean and lubricate pivot points. Replace worn parts.
Excessive vibration	Unbalanced chain, loose components, worn AV mounts	Sharpen chain evenly. Tighten all fasteners. Inspect and replace anti-vibration buffers.
Chain oil not flowing	Empty oil tank, clogged oil passages, faulty pump	Fill tank. Clean bar groove and oil outlet hole. Check oil line from tank to pump. Inspect/replace oil pump.

Reset: For electronic ignition issues, ensure all connections are clean and tight.

Service: For genuine STIHL parts and technical support, contact an authorized STIHL servicing dealer.

Parts Diagrams & List

Exploded-view diagrams for major assemblies with corresponding part numbers.

• Group 1: Crankcase, Cylinder, Piston
• Group 2: Crankshaft, Bearings, Seals
• Group 3: Fuel System (Tank, Lines, Carburetor)
• Group 4: Ignition System (Flywheel, Module)
• Group 5: Clutch, Chain Brake, Oil Pump
• Group 6: Starter Assembly
• Group 7: Anti-Vibration System & Handles
• Group 8: Covers & Housing
• Group 9: Guide Bar & Chain (Various Sizes)

Note: Always use genuine STIHL replacement parts to ensure safety, performance, and warranty compliance.