Husqvarna 445 Operators Manual

The Husqvarna 445 is a robust and reliable chainsaw designed for demanding homeowners and semi-professional users. It features a powerful X-Torq® engine for reduced fuel consumption and emissions, an inertia-activated chain brake for enhanced safety, LowVib® anti-vibration system for operator comfort, and an Air Injection™ air cleaning system for extended air filter life. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: X-Torq® engine, inertia-activated chain brake, combined choke/stop control, side-mounted chain tensioner, Air Injection™ system, and LowVib® handles.

Safety Instructions

Read and understand all instructions before operation. Failure to follow warnings may result in serious injury or death.

1. Personal Protective Equipment (PPE): Always wear chainsaw protective pants, safety glasses, hearing protection, gloves, helmet with face shield, and sturdy boots.
2. Work Area Safety: Keep bystanders and pets at least 15 meters away. Ensure secure footing. Do not operate in poor light, bad weather, or when fatigued.
3. Kickback Zone: Be aware of the upper quadrant of the guide bar tip. Never cut with this part of the bar.
4. Chain Brake: Check function before each use. The chain must stop immediately when the brake is activated.
5. Fuel Safety: Refuel outdoors only, with engine stopped and cool. Use clean, fresh fuel mix (50:1 Husqvarna XP+ oil and 89 octane gasoline).

WARNING! A chainsaw is a dangerous tool if used improperly. Always maintain a firm grip with both hands.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach Guide Bar & Chain: Place bar on mounting studs. Fit chain around sprocket and bar, ensuring cutting teeth face forward on top. Adjust tension with side screw.
2. Fill Fuel & Oil: Add correct fuel/oil mix to fuel tank. Fill bar and chain oil tank with recommended oil.
3. Check Chain Tension: Chain should be snug against the bar but pull freely by hand. Re-tension when cold chain sags from the bar rail.

CAUTION! Ensure the chain brake is disengaged (pulled back toward the front handle) before starting.

Specifications

• Engine Displacement: 45.7 cc
• Engine Power: 2.8 hp (2.1 kW)
• Fuel Consumption: Approx. 470 g/kWh
• Exhaust Emission Level: EPA Phase II, EU Stage II compliant
• Sound Pressure Level at Operator's Ear: 104 dB(A)
• Sound Power Level: 116 dB(A)
• Vibration Levels (Front/Rear Handle): 3.5/4.4 m/s²
• Recommended Fuel Mix: 50:1 (Husqvarna XP+ 2-stroke oil)
• Ignition System: Electronic, air gap 0.3 mm (0.012")
• Spark Plug: Champion RCJ7Y or equivalent, gap 0.5 mm (0.020")

Controls and Components

Familiarize yourself with all controls before starting.

Main Components: Front Handle with chain brake, Rear Handle with throttle trigger and throttle lockout, Combined Choke/Stop Control, Decompression Valve, Inertia-Activated Chain Brake, Side-mounted Chain Tensioner, Air Filter Cover, Fuel and Oil Caps.

Operation: Throttle lockout must be pressed before throttle trigger can be engaged. Chain brake is engaged by pushing the front hand guard forward (manually) or automatically by inertia during kickback.

Starting & Stopping the Saw

Cold Start:

1. Place saw on firm ground. Engage chain brake.
2. Press decompression valve (if equipped).
3. Set combined control to choke position (full up).
4. Pull starter cord sharply until engine fires (max 4-5 pulls).
5. Set combined control to half-throttle position (middle).
6. Pull starter cord again until engine starts.
7. Blip throttle to disengage start setting. Disengage chain brake.

Warm Start: Set combined control to run position (full down). Pull starter cord.

Stopping: Release throttle. Set combined control to STOP position.

Basic Operation & Cutting Techniques

Always use full throttle when cutting.

1. Felling (Cutting Down a Tree): Plan escape path. Make notch cut (1/3 of tree diameter). Make felling cut opposite notch. Use wedges if needed.
2. Limbing: Stand on left side of trunk. Cut branches from top side. Let branch support weight of saw.
3. Bucking (Cutting Logs): Support log properly. Cut from top. For logs under tension, cut from compression side first to avoid pinching.
4. Kickback Prevention: Maintain a firm grip. Do not cut with bar tip. Keep saw chain sharp and properly tensioned.

Tip: Let the chain do the work; do not force the saw.

Maintenance Schedule

CAUTION! Disconnect spark plug wire before performing any maintenance.

Chain Sharpening & Tensioning

A sharp, properly tensioned chain is essential for safety and performance.

1. Sharpening: Use correct round file size (typically 5/32" or 4.0mm). File each cutter at same angle (typically 30°). Maintain equal length on all cutters. File depth gauges with a flat file and gauge.
2. Tensioning: Loosen bar nuts. Turn tensioning screw clockwise until chain is snug against bar bottom. Chain should pull freely by hand. Tighten bar nuts while lifting bar tip. Re-check tension when chain is cold.

WARNING! Always wear heavy gloves when handling the chain.

Storage

Prepare saw for storage if not used for more than 30 days.

1. Empty fuel tank and run engine until it stops to clear carburetor.
2. Remove chain, clean in solvent, dry, and soak in oil. Clean guide bar groove.
3. Clean entire saw. Check for damage.
4. Store in a dry, dust-free place, out of reach of children.

CAUTION! Never store a chainsaw with fuel in the tank for extended periods.

Troubleshooting

Service: For repairs beyond basic maintenance, contact an authorized Husqvarna service dealer.

Support: Husqvarna AB, SE-561 82 Huskvarna, Sweden. www.husqvarna.com