stihl 4308 manual

The STIHL 4308 is a professional-grade chainsaw designed for demanding forestry and arborist work. It features a powerful engine, advanced anti-vibration system, QuickStop® inertia chain brake, STIHL Ematic™ lubrication system, and a decompression valve for easy starting. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Engine, Guide Bar, Saw Chain, Chain Brake Handle, Throttle Trigger, Master Control Lever, Decompression Valve, Fuel and Oil Caps.

Feature	Description
Engine	High-performance 2-stroke engine with decompression valve
Anti-Vibration System	Reduces operator fatigue during extended use
QuickStop® Inertia Chain Brake	Automatically stops chain in kickback situations
STIHL Ematic™ System	Efficient chain lubrication with reduced oil consumption
Master Control Lever	Single lever for choke, start, and run positions
Side Access Chain Tensioner	Allows easy chain adjustment without tools
Fuel and Oil Caps	Large, easy-to-open caps with retaining straps
Spark Arresting Muffler	Reduces fire hazard and exhaust emissions
Ergonomic Handle	Designed for comfort and secure grip
Chain Catcher	Helps reduce risk if chain breaks or derails

Safety Instructions

Read and understand all instructions before operation. Always wear proper PPE.

1. Personal Protective Equipment: Wear safety glasses, hearing protection, gloves, chainsaw chaps, and sturdy boots.
2. Work Area Safety: Keep bystanders and pets at least 15 feet away. Clear area of tripping hazards.
3. Chain Brake Check: Verify chain brake function before each use by engaging it against a log.
4. Fuel Safety: Refuel in well-ventilated area, away from ignition sources. Use STIHL MotoMix® or proper fuel/oil mix.

WARNING! Kickback can occur without warning, causing severe injury. Always hold saw firmly with both hands.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach Guide Bar: Remove bar cover nuts, position bar on studs, ensure chain tensioning pin engages in bar hole.
2. Install Saw Chain: Place chain on bar with cutting edges facing forward on top. Ensure drive links engage in sprocket.
3. Adjust Chain Tension: Loosen bar nuts, turn adjustment screw until chain fits snug against bar, then tighten nuts.
4. Fill Fluids: Add STIHL 2-stroke engine oil to fuel (50:1 ratio for MotoMix®). Fill bar and chain oil reservoir.

CAUTION! Chain must be properly tensioned. A loose chain can derail; an overtightened chain can damage the engine.

Specifications

• Engine Displacement: 65.6 cc.
• Power Output: 4.4 bhp.
• Fuel Capacity: 24.3 fl. oz.
• Oil Capacity: 11.8 fl. oz.
• Guide Bar Lengths: 16" to 25" (recommended).
• Chain Pitch: 3/8" or .325".
• Weight (powerhead): 14.6 lbs.
• Sound Pressure Level: 112 dB(A).
• Vibration Levels: Front handle 4.5 m/s², rear handle 3.5 m/s².
• Warranty: Limited 1-year commercial warranty.

Controls and Components

Master Control Lever: Combines choke, start, and run functions. Chain Brake Handle: Front hand guard that activates brake when pushed forward. Throttle Trigger: Controls engine speed; includes throttle trigger interlock. Decompression Valve: Reduces compression for easier starting. Stop Switch: Turns ignition off.

Maintenance Points: Air filter, spark plug, fuel filter, chain tensioner, bar oil ports.

Safety Features: Chain catcher, right-hand guard, muffler with spark arrestor, anti-vibration system.

Starting & Stopping

Cold Start Procedure:

1. Engage chain brake by pushing handle forward.
2. Set Master Control Lever to choke position (full down).
3. Press decompression valve (if equipped).
4. Place saw on firm ground, hold handle with left hand, place right foot in rear handle.
5. Pull starter rope briskly until engine fires (usually 2-5 pulls).
6. Move Master Control Lever to half-throttle position.
7. Pull starter rope again until engine starts.
8. Briefly press throttle to disengage fast idle.

Warm Start: Set Master Control Lever to run position; pull starter rope.

Stopping: Release throttle, press stop switch to "0".

Operation Guidelines

Proper cutting techniques ensure safety and efficiency.

1. Stance: Stand with feet shoulder-width apart, left foot slightly forward.
2. Grip: Hold front handle with left hand, rear handle with right hand. Thumbs wrapped underneath.
3. Starting Cut: Allow chain to reach full speed before contacting wood.
4. Kickback Zone: Avoid cutting with upper quadrant of bar tip.
5. Pushing/Pulling: Let saw do the work; avoid forcing through cut.
6. Bucking: Support log properly; cut from top down for most situations.
7. Limbing: Work from trunk outward; be aware of spring-loaded branches.

Tip: Maintain sharp chain; a dull chain requires more force and increases kickback risk.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Interval	Task
Before each use	Check chain tension, brake function, fluid levels
Every 5 hours	Clean air filter, check spark plug
Every 20 hours	Replace fuel filter, clean spark arrestor screen
Every 100 hours	Clean cylinder fins, check all fasteners
Annually	Professional servicing recommended

CAUTION! Always disconnect spark plug wire before performing maintenance.

Chain & Bar Care

Proper chain maintenance is critical for safe operation.

1. Sharpening: Use round file matching chain pitch (typically 5/32" or 7/32"). Maintain 30° cutting angle.
2. Depth Gauges: File rakers to proper height (0.025" below cutter edge) with depth gauge tool.
3. Bar Maintenance: Clean bar groove weekly. Flip bar monthly for even wear. Dress bar rails if burred.
4. Lubrication: Ensure oiler is working; adjust flow if needed. Use STIHL bar and chain oil for best results.

WARNING! Always wear gloves when handling chain. A sharp chain is safer than a dull one.

Storage

Proper storage prevents fuel system issues.

1. Short-term (under 30 days): Add fuel stabilizer to fresh fuel, run engine 2 minutes to circulate.
2. Long-term: Drain fuel tank completely. Run engine until it stops to clear carburetor. Remove chain and store separately.
3. Location: Store in dry, secure area away from children. Cover to prevent dust accumulation.

CAUTION! Never store with fuel in tank for more than 30 days without stabilizer.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, old fuel	Check spark plug; wait if flooded; use fresh fuel mix.
Engine starts then dies	Clogged fuel filter, air leak	Replace fuel filter; check fuel lines and carburetor.
Poor cutting performance	Dull chain, improper tension	Sharpen chain; adjust tension; check bar lubrication.
Excessive vibration	Loose components, unbalanced chain	Tighten all fasteners; check chain for damaged cutters.
Chain won't stop when brake engaged	Worn brake band, dirty mechanism	Clean brake components; replace brake band if worn.
Chain oil not flowing	Clogged oil ports, empty reservoir	Clean oil ports; refill with proper bar oil; check oil pump.

Service: For repairs beyond basic maintenance, contact authorized STIHL servicing dealer.

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