Husqvarna 440 Chainsaw Parts Manual

The Husqvarna 440 Chainsaw is a professional-grade power tool designed for demanding cutting tasks. This parts manual provides detailed information on all components, assembly, maintenance, and replacement procedures to ensure optimal performance and safety. Below are key sections covering safety warnings, parts identification, assembly instructions, maintenance schedules, and troubleshooting.

1. Safety Warnings & Precautions 2. Parts Identification & Diagram 3. Assembly Instructions 4. Technical Specifications 5. Maintenance & Servicing 6. Fuel & Lubrication System 7. Chain & Bar Assembly 8. Ignition System 9. Carburetor Adjustment 10. Warranty Information 11. Troubleshooting Guide

Safety Warnings & Precautions

Essential safety information to prevent injury and damage. Always read before operation.

Warning	Description
Personal Protective Equipment	Always wear safety glasses, hearing protection, gloves, and chainsaw chaps.
Kickback Zone	Avoid contact with upper quadrant of guide bar tip to prevent kickback.
Fuel Safety	Refuel in well-ventilated area with engine off and cool. Use fuel mix ratio 50:1.
Chain Brake	Test chain brake function before each use. Ensure it engages properly.
Two-Hand Operation	Always grip saw firmly with both hands during operation.
Hot Surfaces	Avoid contact with muffler and cylinder during/after operation.
Chain Tension	Check and adjust chain tension frequently; a loose chain may derail.
Sharp Chain	Use only sharp chains; dull chains increase risk of kickback.
Working Area	Clear work area of obstacles and ensure secure footing.
Emergency Stop	Familiarize yourself with STOP switch location and operation.

Parts Identification & Diagram

Key components and their part numbers for reference and ordering.

Front Hand Guard / Chain Brake: Part # 503 92 47-01
Chain Catcher: Part # 501 87 64-01
Guide Bar (16"): Part # 531 00 42-16
Sprocket Nose: Part # 501 84 65-01
Chain (3/8" LP, .050 gauge): Part # 531 30 04-48
Clutch Drum & Sprocket: Part # 503 87 26-01
Clutch Assembly: Part # 503 87 25-01
Starter Assembly: Part # 537 27 40-01
Air Filter Cover: Part # 537 27 39-01
Carburetor (Zama C1Q-S267): Part # 545 01 13-01
Ignition Module: Part # 537 27 38-01
Fuel Tank: Part # 537 27 37-01
Oil Pump: Part # 503 87 24-01
Muffler: Part # 537 27 36-01
Cylinder & Piston Kit: Part # 537 27 35-01

WARNING! Use only genuine Husqvarna replacement parts to maintain safety and performance.

Assembly Instructions

Steps to assemble your chainsaw from the box for first-time use.

Attach Guide Bar & Chain: Place bar on studs, align chain with drive sprocket, tension correctly, tighten bar nuts.
Install Chain Brake Handle: Ensure front hand guard moves freely and engages brake band.
Fill Fuel & Oil Tanks: Use Husqvarna XP+ 2-stroke oil at 50:1 ratio for fuel. Fill bar/chain oil reservoir.
Check Chain Tension: Adjust via side tensioning screw until chain snaps back when pulled from bar.
Test Safety Features: Verify chain brake, throttle lock, and stop switch function before starting.

CAUTION! Do not start engine until assembly is complete and all fasteners are tightened.

Technical Specifications

Engine Displacement: 40.9 cc (2.5 cu in).
Power Output: 2.4 kW (3.2 hp).
Fuel Tank Volume: 0.33 L (0.87 US pt).
Oil Tank Volume: 0.25 L (0.53 US pt).
Recommended Bar Lengths: 13" to 18".
Chain Pitch/Gauge: 3/8" LP, .050".
Idle Speed: 2,700 RPM.
Maximum Power Speed: 9,000 RPM.
Ignition System: Electronic, air gap 0.30 mm.
Weight (Powerhead): 4.4 kg (9.7 lbs).
Sound Pressure Level: 106 dB(A).
Vibration Levels: Front/ Rear Handle: 3.5/4.5 m/s².

Maintenance & Servicing

Routine maintenance schedule and procedures.

Daily/Before Use: Check chain tension and sharpness, inspect guide bar for wear, clean air filter, check all fasteners.

Weekly/Every 10 Hours: Clean cooling fins, check spark plug condition (gap 0.5 mm), clean fuel filter, inspect anti-vibration elements.

Monthly/Every 50 Hours: Clean carburetor air intake, replace spark plug (NGK BPMR7A), clean exhaust port and spark arrestor screen.

Annually/Every 100 Hours: Replace fuel filter, inspect and clean clutch assembly, check oil pump output, replace air filter if damaged.

Fuel & Lubrication System

Proper fuel mix and bar/chain oil specifications.

Fuel: Use 89 octane or higher unleaded gasoline mixed with Husqvarna XP+ 2-stroke oil at 50:1 ratio (20 ml oil per 1 liter gas).
Bar & Chain Oil: Use Husqvarna Biodegradable Chain Oil or equivalent SAE 30 weight. Check oil flow by running saw at full throttle over light surface.
Oil Pump Adjustment: Located under clutch cover. Turn screw clockwise to increase flow, counterclockwise to decrease.

Tip: Always shake fuel mix before refueling. Never use automotive motor oil or straight gasoline.

Chain & Bar Assembly

Installation, tensioning, and maintenance of cutting equipment.

Bar Installation: Ensure groove is clean, align holes with studs, position so oil holes align with oil pump outlet.
Chain Installation: Place chain over sprocket, ensure cutting teeth face forward on top of bar, engage drive links in bar groove.
Tensioning: Loosen bar nuts, turn tensioning screw until chain is snug against bar, lift tip to check snap-back, tighten bar nuts.
Sharpening: Use 4.0 mm round file at 30° angle, maintain equal tooth length, file depth gauges with flat file.
Rotation: Flip bar weekly to ensure even wear on both sides.

WARNING! Always wear gloves when handling chain. Stop engine before adjusting or servicing.

Ignition System

Components and service procedures for ignition system.

Spark Plug: NGK BPMR7A (Champion RCJ7Y), gap 0.5 mm. Replace if electrode is worn or insulator cracked.

Ignition Module: Air gap setting 0.30 mm. Check for spark by removing plug, grounding against cylinder, and pulling starter.

Stop Switch: Test continuity; replace if circuit fails to interrupt spark.

Carburetor Adjustment

Factory settings and adjustment procedures for Zama C1Q-S267 carburetor.

Initial Settings: L screw: 1 turn out. H screw: 1 turn out. T screw: 1 turn out.

Warm up engine for 5 minutes before adjusting.
Adjust Idle (T): Turn until chain just starts to move, then back off 1/4 turn.
Adjust Low Speed (L): Turn for smoothest acceleration from idle.
Adjust High Speed (H): Use tachometer to set maximum speed to 9,000 RPM (±200 RPM).

CAUTION! Over-leaning H screw can cause engine damage. Final adjustment should be performed by authorized dealer.

Warranty Information

Husqvarna 440 comes with a 2-year consumer warranty for private users, 1-year professional warranty. Warranty covers defects in materials and workmanship. Not covered: normal wear, misuse, improper maintenance, non-genuine parts. Keep purchase receipt for warranty validation. For claims, contact authorized Husqvarna service dealer.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine will not start	No spark, flooded, fuel issue	Check spark plug, dry plug, use fresh fuel mix, check fuel filter.
Engine starts then dies	Clogged air filter, carb adjustment	Clean/replace air filter, check fuel vent, adjust carburetor.
Poor acceleration	Dirty spark arrestor, L screw	Clean spark arrestor screen, adjust L screw richer.
Chain does not oil	Empty oil tank, clogged passages	Fill tank, clean oil holes in bar, check pump function.
Excessive vibration	Loose components, unbalanced chain	Tighten all fasteners, sharpen chain evenly, check anti-vibration mounts.
Chain throws off bar	Loose chain, worn bar, damaged drive links	Adjust tension, inspect bar groove, replace chain if damaged.
Overheating	Dull chain, lean mixture, dirty cooling fins	Sharpen chain, adjust carburetor, clean cylinder fins.

Service: For technical support or parts ordering, contact Husqvarna at 1-800-487-5962 or visit www.husqvarna.com/us.