Stihl 084 Manual

The Stihl 084 is a professional-grade chainsaw designed for heavy-duty forestry and logging applications. It features a powerful engine, robust construction, and advanced safety systems for demanding cutting tasks. Below are key sections covering safety, features, operation, maintenance, troubleshooting, and technical specifications.

Features at a Glance

Key components: High-performance engine, anti-vibration system, QuickStop chain brake, decompression valve, adjustable oil pump, and ergonomic handles.

Feature	Description
Engine Type	2-stroke, single cylinder, air-cooled
Displacement	121.6 cc
Power Output	6.4 kW (8.6 hp)
Fuel Tank Capacity	1100 ml
Oil Tank Capacity	650 ml
Guide Bar Length Range	Up to 105 cm (41 inches)
Weight (without bar/chain)	9.2 kg (20.3 lbs)
Ignition System	Electronic, capacitor discharge
Chain Brake	QuickStop inertia-activated
Anti-Vibration System	Spring-mounted handles

Safety Instructions

Read all instructions before operation. Always wear appropriate PPE.

1. Personal Protective Equipment: Wear safety helmet, hearing protection, eye protection, gloves, chainsaw chaps, and sturdy boots.
2. Work Area Safety: Clear area of obstacles and bystanders. Ensure secure footing.
3. Fuel Safety: Refuel in well-ventilated area with engine off and cool. Use approved fuel mix.
4. Kickback Prevention: Maintain secure grip; avoid contact with bar tip.
5. Chain Brake: Test before each use; engage when not cutting.

WARNING! Failure to follow safety instructions can result in serious injury or death. Never operate when fatigued or under influence.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach guide bar: Place bar onto studs, align chain tensioning pin.
2. Install chain: Ensure cutting teeth face forward on top of bar.
3. Tension chain: Adjust tensioning screw until chain snaps back when pulled from bar.
4. Fill tanks: Add fuel mix (50:1 gasoline to 2-stroke oil) to fuel tank. Add bar and chain oil to oil tank.
5. Check controls: Ensure throttle trigger, throttle lockout, and chain brake function properly.

CAUTION! Use only genuine Stihl replacement parts. Incorrect assembly can cause malfunction.

Specifications

• Model: Stihl 084 AV
• Engine Power: 6.4 kW at 8000 rpm
• Max Engine Speed: 12500 rpm
• Fuel Consumption: Approx. 680 g/kWh
• Sound Pressure Level: 112 dB(A)
• Vibration Levels: Front handle: 5.2 m/s², Rear handle: 4.8 m/s²
• Spark Plug: Bosch WSR6F or equivalent
• Recommended Fuel: Minimum 90 octane unleaded gasoline with Stihl HP Ultra 2-stroke oil
• Warranty: 12 months commercial use, 24 months private use

Controls and Functions

Main controls located on top and rear handle.

Front Handle: Chain brake lever, throttle lockout, hand guard. Rear Handle: Throttle trigger, master control lever (choke/run/stop), decompression valve, primer bulb.

Master Control Lever Positions: STOP (0) - engine off; RUN (I) - normal operation; CHOKE (II) - cold start. Decompression Valve: Press to reduce compression for easier starting. Chain Brake: Manual activation via front hand guard; inertia-activated during kickback.

Starting & Operation

Starting procedure for cold and warm engine.

1. Place saw on clear, level ground. Engage chain brake.
2. Set master control to CHOKE (II). Press decompression valve.
3. Press primer bulb 5-10 times until fuel is visible.
4. Hold rear handle with right foot, pull starter rope briskly until engine fires.
5. Move master control to RUN (I). Pull starter rope to start engine.
6. Disengage chain brake before cutting.
7. During operation: Maintain firm grip, use full throttle for cutting, avoid pinching bar.
8. Shutting down: Release throttle, set master control to STOP (0).

Tip: Allow engine to warm up at idle for 30 seconds before cutting.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Interval	Task
Daily	Check chain tension, sharpness, and lubrication; clean air filter; inspect bar for wear
Weekly	Clean spark arrestor screen; check fuel filter; inspect anti-vibration elements
Monthly	Replace spark plug; clean cooling fins; check clutch and sprocket
Annually	Replace fuel lines; clean carburetor; check cylinder compression
As needed	Replace worn bar; sharpen or replace chain; replace air filter

WARNING! Perform maintenance only when engine is off and cool. Disconnect spark plug wire for safety.

Chain & Bar Care

Proper chain maintenance ensures efficient cutting and safety.

1. Sharpening: Use round file matching chain pitch (typically 3/8" or .404"). Maintain 30° filing angle.
2. Tensioning: Chain should snap back when pulled from bar. Adjust when chain is warm.
3. Bar Maintenance: Clean bar groove weekly; flip bar monthly for even wear.
4. Lubrication: Ensure oil port is clear; adjust oil pump for proper flow.
5. Storage: Clean and oil chain and bar before long-term storage.

CAUTION! Dull chain increases kickback risk. Replace chain when cutting teeth are worn below 4mm.

Storage Guidelines

Proper storage prevents fuel system issues and corrosion.

1. Short-term (under 30 days): Fill fuel tank with fresh mix; run engine 2 minutes to circulate.
2. Long-term (over 30 days): Drain fuel tank and carburetor completely. Run engine until it stops.
3. Remove chain and bar; clean and oil thoroughly.
4. Store in dry, cool place with chain brake engaged.
5. Before reuse: Refill with fresh fuel mix; check all systems.

CAUTION! Never store with fuel in tank for extended periods. Old fuel can damage engine.

Warranty Information

Stihl Limited Warranty: 12 months for commercial use, 24 months for private use from date of purchase. Covers defects in materials and workmanship. Does not cover normal wear, misuse, improper maintenance, or non-genuine parts. Proof of purchase required. For warranty service, contact authorized Stihl dealer. For support, visit www.stihl.com or contact 1-800-467-8445.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	No fuel, flooded, spark plug	Check fuel; wait if flooded; clean/replace spark plug.
Engine runs poorly	Dirty air filter, carburetor	Clean/replace air filter; adjust carburetor.
Chain doesn't turn	Brake engaged, clutch, sprocket	Disengage brake; check clutch springs; replace sprocket.
Excessive vibration	Loose parts, worn AV mounts	Tighten all fasteners; replace anti-vibration elements.
Chain not oiling	Empty tank, clogged port, pump	Fill oil tank; clean oil ports; adjust/replace oil pump.
Overheating	Dirty cooling fins, lean mixture	Clean cooling fins; adjust carburetor richer.

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

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