Husqvarna Chainsaw 345 Repair Manual

The Husqvarna Chainsaw 345 is a professional-grade chainsaw designed for demanding cutting tasks. This repair manual provides comprehensive instructions for maintenance, troubleshooting, and repair of the saw's engine, fuel system, cutting equipment, and safety features. Below are key sections covering safety warnings, specifications, routine maintenance, disassembly, component repair, and reassembly procedures.

1. Safety Warnings & Precautions 2. Technical Specifications 3. Tools & Workshop Requirements 4. Routine Maintenance Schedule 5. Engine System Repair 6. Fuel System Repair 7. Ignition System Repair 8. Chain & Bar Maintenance 9. Clutch & Drive System 10. Troubleshooting Guide 11. Parts List & Diagrams

Safety Warnings & Precautions

Before performing any repair, read all safety instructions. Always wear appropriate personal protective equipment (PPE).

Hazard	Precaution
Fuel & Fire	Work in well-ventilated area; no smoking or open flames.
Sharp Components	Wear cut-resistant gloves when handling chain or bar.
Hot Surfaces	Allow engine to cool completely before disassembly.
Spring Tension	Use proper tools when handling clutch or starter springs.
Electrical Shock	Disconnect spark plug wire before working on ignition system.

Technical Specifications

Model: Husqvarna 345
Engine Type: 2-stroke, single cylinder
Displacement: 45.7 cc
Power Output: 2.2 kW (3.0 hp)
Fuel Tank Capacity: 0.47 L
Oil Tank Capacity: 0.26 L
Recommended Bar Length: 13" to 18" (33 cm to 45 cm)
Chain Pitch: 3/8" or .325"
Ignition System: Electronic, SEM
Weight (Powerhead): 4.7 kg (10.4 lbs)

Tools & Workshop Requirements

Gather necessary tools before starting repair.

Standard tool set: Screwdrivers, wrenches, socket set.
Specialty tools: Piston stop, flywheel puller, clutch tool, compression tester.
Cleaning supplies: Carburetor cleaner, parts washer, compressed air.
Measuring tools: Feeler gauges, caliper, spark plug gap tool.

WARNING! Use only Husqvarna-approved replacement parts. Improper tools can damage components.

Routine Maintenance Schedule

Follow this schedule to prevent major repairs.

Daily: Clean air filter, check chain tension and sharpness, inspect for loose fasteners.
Weekly: Clean cooling fins, check spark plug condition, clean fuel filter.
Monthly: Clean carburetor (external), check fuel lines for cracks, inspect clutch drum.
Seasonally: Replace spark plug, clean muffler screen, check piston through exhaust port.
Annually: Replace fuel filter, check compression, inspect anti-vibration mounts.

CAUTION! Always use fresh, high-quality 2-stroke oil mixed at 50:1 ratio with unleaded gasoline.

Engine System Repair

Cylinder, piston, crankshaft, and bearings.

Compression Test: Attach tester to spark plug hole, pull starter rope. Minimum 120 psi required.

Piston & Cylinder Inspection: Remove muffler to view piston through exhaust port. Look for scoring. Deep scratches indicate need for replacement.

Crankshaft Seal Replacement: Remove clutch and flywheel. Pry out old seals. Press new seals flush with case.

Fuel System Repair

Carburetor, fuel lines, tank, and filter.

Remove carburetor cover and air filter.
Disconnect fuel lines and throttle linkage.
Disassemble carburetor: Remove diaphragms, gaskets, jets.
Clean all parts in carburetor cleaner. Blow out passages with compressed air.
Reassemble with new kit (diaphragms, gaskets, needle valve).
Reinstall and adjust idle (L) and high-speed (H) screws to factory settings.

Tip: Always replace fuel lines if hardened or cracked. Use ethanol-resistant lines.

Ignition System Repair

Spark plug, coil, flywheel, and wiring.

Check spark: Remove plug, reconnect wire, ground plug against cylinder, pull starter. Look for strong blue spark.
Spark Plug Gap: Set to 0.020" (0.5 mm).
Coil Air Gap: Set between flywheel magnets and coil legs to 0.010" (0.25 mm) using feeler gauge.
Flywheel Key: Inspect for shearing. Replace if damaged to maintain timing.
Stop Switch: Test continuity. Replace if circuit is always open or closed.

WARNING! Never pull starter with spark plug disconnected and wire grounded—can damage coil.

Chain & Bar Maintenance

Sharpening, tensioning, and replacement.

Sharpening: Use correct round file size for chain. Maintain 30° cutting angle and 10° top plate angle. File all cutters to equal length.

Tensioning: Loosen bar nuts. Adjust tensioning screw until chain snaps back when pulled from bar. Tighten bar nuts with bar tip raised.

Bar Maintenance: Clean bar groove. Flip bar weekly for even wear. Dress rails with flat file if burred.

Clutch & Drive System

Clutch, drum, sprocket, and drive shaft.

Remove clutch: Use clutch tool to hold piston, turn clutch clockwise (left-hand thread).
Inspect clutch shoes for wear and springs for fatigue.
Replace drum if deeply grooved by chain.
Lubricate drive shaft bearing with high-temperature grease.
Reassemble: Torque clutch to 35-40 Nm.

CAUTION! Do not run saw without bar and chain—clutch can over-rev and fail.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, fuel issue	Check spark, dry plug, clean carburetor, fresh fuel.
Engine starts then dies	Clogged fuel filter, carb adjustment	Replace filter, adjust L screw, check tank vent.
Loss of power	Clogged air filter, muffler screen, low compression	Clean filter/screen, test compression, inspect piston.
Chain won't turn	Clutch worn, sprocket seized, brake engaged	Inspect clutch, lubricate sprocket, disengage chain brake.
Excessive vibration	Loose components, damaged AV mounts, unbalanced chain	Tighten fasteners, replace mounts, sharpen chain evenly.

Reset: For electronic ignition module, disconnect battery (if equipped) for 30 seconds.

Service: Authorized Husqvarna service centers. Visit www.husqvarna.com for dealer locator.