Husqvarna 45 Chainsaw Manual

The Husqvarna 45 is a professional-grade chainsaw designed for demanding forestry and land-clearing work. It features a powerful 45cc engine, X-Torq technology for reduced emissions and fuel consumption, an inertia-activated chain brake, LowVib anti-vibration system, and an ergonomic design for operator comfort. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 45cc X-Torq engine, 16" or 18" guide bar, inertia-activated chain brake, combined choke/stop control, air injection centrifugal cleaning, LowVib system.

Safety Instructions

Read and understand all safety warnings before operation.

1. Personal Protective Equipment (PPE): Always wear chainsaw chaps, safety glasses, hearing protection, gloves, and steel-toed boots.
2. Clear Work Area: Ensure no bystanders, especially children, are within 15 feet (5 meters).
3. Kickback Zone: Avoid contact with the upper quarter of the guide bar tip.
4. Secure Workpiece: Never cut while holding the saw with one hand or while on a ladder.
5. Fuel Safety: Refuel outdoors, with engine off and cool. Use clean, unleaded gasoline mixed with 2-stroke oil (50:1 ratio).

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

Assembly & Preparation

Unpack and inspect contents. Assemble on a clean, flat surface.

1. Attach Guide Bar & Chain: Place bar over studs, align chain with drive sprocket and bar groove, tension correctly.
2. Fill Fuel Tank: Use Husqvarna XP+ 2-stroke oil or equivalent JASO FD-rated oil at a 50:1 mix ratio with unleaded gasoline (min. 89 octane).
3. Fill Chain Oil Tank: Use Husqvarna chain oil or a quality biodegradable bar & chain oil.
4. Check Chain Tension: New chain stretches; re-tension after first 10 minutes of use.

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

Specifications

• Model: Husqvarna 45
• Engine Displacement: 45 cc (2.75 cu. in.)
• Power Output: 2.2 kW (3.0 hp)
• Max Power Speed: 9,000 rpm
• Idle Speed: 2,700 rpm
• Recommended Guide Bar Length: 16" (40 cm)
• Chain Pitch: 3/8" or .325" (check model)
• Chain Gauge: 0.050" (1.3 mm)
• Sound Pressure Level (at operator's ear): 104 dB(A)
• Sound Power Level: 116 dB(A)
• Vibration Level (front/rear handle): 3.5/4.5 m/s²

Controls and Components

Familiarize yourself with all controls before starting.

Right Side: Throttle trigger, throttle lockout, rear handle, choke/stop control (combined), primer bulb (on some models).

Left Side: Front handle with hand guard, inertia chain brake, chain brake lever (manual activation), chain catcher, muffler.

Top/Rear: Fuel tank cap, chain oil tank cap, decompression valve (if equipped), air filter cover, starter handle, master control lever (choke/fast idle/run).

Starting & Stopping

Cold Start:

1. Place saw on flat ground. Engage chain brake (push forward).
2. Press decompression valve (if equipped).
3. Set master control lever to choke position (full down).
4. Press primer bulb 4-6 times (if equipped).
5. Pull starter cord sharply until engine fires (1-3 pulls).
6. Move master control lever up to fast idle/half-throttle position.
7. Pull starter cord again until engine starts. Let run for 10-15 seconds.
8. Blip throttle to disengage fast idle. Disengage chain brake (pull back).

Warm Start: Set master control to fast idle/half-throttle position. Pull starter cord.

Stopping: Release throttle. Move master control lever to STOP position.

Operating Instructions

Proper technique ensures 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. Thumb wrapped under.
3. Starting Cut: Let chain reach full speed before contacting wood. Use bumper spikes to pivot saw into cut.
4. Kickback Prevention: Maintain a firm grip. Do not cut with the tip. Be aware of tension in wood.
5. Refueling: Stop engine and let cool for 5 minutes. Clean area around caps. Refill both fuel and chain oil tanks.

Tip: Let the saw do the work; do not force it. Keep chain sharp and properly tensioned.

Maintenance Schedule

Chain Sharpening & Tensioning

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

1. Tensioning: Loosen bar nuts. Use tensioning screw to raise bar until chain fits snugly against bar (can be pulled by hand with light resistance). Retighten bar nuts. Re-check tension when chain is cold.
2. Sharpening: Use a round file matching chain pitch (typically 5/32" or 4.0mm). Maintain factory filing angle (typically 30°). File all cutters to equal length. File depth gauges with a flat file and gauge.

WARNING! Always wear heavy gloves when handling the chain. Stop engine and disconnect spark plug wire before performing maintenance.

Storage

Proper storage prevents fuel system issues and corrosion.

1. Drain all fuel from tank and carburetor. Run engine until it stops.
2. Remove chain, clean in solvent, dry, and coat with oil. Store separately.
3. Clean entire saw, especially cooling fins and air filter area.
4. Store in a dry, cool place, protected from dust and moisture.

CAUTION! Never store with fuel in the tank for more than 30 days. Old fuel can damage carburetor seals and diaphragms.

Troubleshooting

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

Support: Husqvarna AB, SE-561 82 Huskvarna, Sweden. In USA: 1-800-487-5962 or www.husqvarna.com/us