Husqvarna 350 Chainsaw Repair Manual

The Husqvarna 350 is a professional-grade chainsaw featuring a 50.1cc engine, 18-inch bar length, X-Torq engine technology for reduced emissions, Smart Start system for easier starting, LowVib anti-vibration system, combined choke/stop control, inertia-activated chain brake, and air injection centrifugal cleaning. This manual provides comprehensive repair, maintenance, and troubleshooting guidance for owners and technicians.

Safety Precautions

Always prioritize safety when operating or repairing the Husqvarna 350 chainsaw.

Precaution	Description
Personal Protective Equipment	Wear safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toed boots
Work Area Safety	Clear area of bystanders, especially children; ensure secure footing
Chain Brake Check	Test inertia and manual chain brake function before each use
Fuel Safety	Refuel in well-ventilated area with engine off and cool; use fuel mix 50:1 (Husqvarna XP oil)
Kickback Awareness	Be aware of kickback zone (upper quadrant of bar tip); use reduced-kickback chain
Maintenance Safety	Disconnect spark plug wire before performing repairs; ensure chain is stopped
Transport & Storage	Engage chain brake; fit scabbard over bar; store fuel separately in approved container
First Aid	Keep first aid kit accessible; know emergency procedures for cuts

Specifications

• Engine Type: 2-stroke, single cylinder
• Displacement: 50.1 cc (3.06 cu. in.)
• Power Output: 3.2 hp (2.4 kW)
• Fuel Tank Volume: 0.95 L (0.25 US gal)
• Oil Tank Volume: 0.26 L (0.07 US gal)
• Recommended Bar Length: 15" - 18" (38 cm - 45 cm)
• Chain Pitch: 3/8" or 0.325"
• Chain Gauge: 0.058" (1.5 mm) or 0.050" (1.3 mm)
• Idle Speed: 2700 RPM
• Maximum Power Speed: 9600 RPM
• Ignition System: Electronic, air gap 0.3 mm (0.012")
• Spark Plug: NGK BPMR7A, gap 0.5 mm (0.020")
• Weight (powerhead): 5.2 kg (11.5 lbs)

Component Identification

Key components of the Husqvarna 350 chainsaw.

1. Front Handle: With throttle trigger and throttle lockout.
2. Rear Handle: With start/stop switch and choke control.
3. Chain Brake Handle: Front hand guard activates manual chain brake.
4. Air Filter Cover: Quick-release clips for access to air filter.
5. Muffler: Equipped with spark arrestor screen.
6. Chain Tensioner: Side-mounted adjustment screw.
7. Fuel & Oil Caps: Clearly marked with symbols.
8. Decompression Valve: Reduces compression for easier starting.
9. Spark Plug Cover: Protects spark plug and wire.

WARNING! Never operate chainsaw with missing or damaged safety components.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Interval	Task
Daily/Before Use	Check chain tension, sharpness, and lubrication; inspect for loose fasteners; test chain brake
Every 10 Hours	Clean air filter; check spark plug condition and gap; clean cooling fins
Every 20 Hours	Clean spark arrestor screen in muffler; inspect fuel filter; check anti-vibration elements
Every 50 Hours	Replace fuel filter; clean carburetor air intake; inspect clutch and sprocket
Every 100 Hours	Replace spark plug; clean cylinder and piston; check ignition system
Seasonally/As Needed	Replace bar and chain; rebuild carburetor; replace fuel lines

Engine Repair

Procedures for common engine repairs.

1. Cylinder & Piston Inspection: Remove muffler to inspect piston through exhaust port for scoring.
2. Cylinder Replacement: Remove starter assembly, fuel tank, and intake components to access cylinder bolts.
3. Crankcase Sealing: Check for air leaks using pressure/vacuum test; replace seals if leaking.
4. Connecting Rod Bearing: Check for up/down play; replace crankshaft assembly if excessive.
5. Decompression Valve: Test by pressing; replace if stuck open or leaking compression.

CAUTION! Use factory torque specifications when reassembling engine components.

Fuel System

Fuel system components and service procedures.

1. Fuel Lines: Two lines (supply and return) inside tank; replace if cracked or hardened.
2. Fuel Filter: Located inside fuel tank; replace by pulling through filler neck with wire hook.
3. Carburetor: Walbro HDA or Zama C1M; includes H (high), L (low), and T (idle) adjustment screws.
4. Fuel Pump Diaphragm: Inspect for stiffness or cracks; replace carburetor kit if damaged.
5. Fuel Tank Vent: Located in cap; ensure it breathes freely to prevent vapor lock.

Tip: Always use fresh fuel mix (max 30 days old) to prevent carburetor issues.

Ignition System

Ignition testing and component replacement.

1. Spark Test: Remove spark plug, ground electrode to cylinder, pull starter to check for spark.
2. Ignition Module: Check air gap (0.3 mm) between flywheel and module poles.
3. Stop Switch Test: