Husqvarna 359 Chainsaw Repair Manual

The Husqvarna 359 is a professional-grade chainsaw featuring a 59cc engine, X-Torq technology for reduced emissions and fuel consumption, combined choke/stop control, air injection centrifugal air cleaning system, inertia activated chain brake, and low vibration design. This manual provides comprehensive repair, maintenance, and troubleshooting guidance for owners and technicians. Below are key sections covering safety, specifications, disassembly, engine service, fuel system, ignition, cutting equipment, and troubleshooting procedures.

1. Safety Precautions 2. Specifications & Technical Data 3. Tools & Equipment Required 4. Routine Maintenance 5. Engine Disassembly & Assembly 6. Fuel System Service 7. Ignition System 8. Carburetor Adjustment 9. Chain & Bar Maintenance 10. Troubleshooting Guide 11. Parts List & Diagrams

Safety Precautions

Always prioritize safety when performing repairs. Disconnect spark plug wire before any service. Use proper personal protective equipment (PPE).

Hazard	Precaution
Fuel handling	Work in well-ventilated area; no smoking or open flames
Sharp components	Wear cut-resistant gloves when handling chain, bar, or sprocket
Hot surfaces	Allow engine to cool completely before disassembly
Spring tension	Use caution when removing clutch, starter assembly; springs can cause injury
Electrical shock	Disconnect ignition coil before testing; avoid contact with spark plug wire

Specifications & Technical Data

Engine: 59cc, 2-stroke, X-Torq
Power Output: 3.5 kW (4.7 hp)
Fuel Capacity: 0.75 L (0.2 US gal)
Oil Capacity: 0.3 L (0.08 US gal)
Bar Lengths: 15" to 20" (38 cm to 50 cm)
Chain Pitch: 3/8" or .325"
Spark Plug: NGK BPMR7A (gap 0.5 mm / 0.020")
Idle Speed: 2700 RPM
Max Power Speed: 9600 RPM
Weight (powerhead): 5.9 kg (13.0 lbs)

Tools & Equipment Required

Standard metric tool set, Torx drivers (T27), spark plug wrench, piston stop, flywheel puller, compression tester, vacuum/pressure tester for crankcase, carburetor adjustment tool, feeler gauges.

Disconnect spark plug wire.
Clean exterior to prevent debris entering engine.
Organize removed parts in order of disassembly.
Use manufacturer-specified torque values during reassembly.

WARNING! Use genuine Husqvarna tools or equivalents to avoid damage.

Routine Maintenance

Daily/Pre-use: Check chain tension, sharpness, bar condition, fuel/oil levels, air filter, cooling fins, chain brake function.

Air filter: Remove, clean with compressed air or wash in soapy water (if foam). Replace if damaged.
Spark plug: Inspect electrode; clean or replace as needed. Set gap to 0.5 mm.
Fuel filter: Replace annually or if clogged.
Chain oiler: Test flow; clean outlet hole in bar.
Bar maintenance: File rails; flip bar regularly for even wear.

CAUTION! Always use Husqvarna XP+ 2-stroke oil at 50:1 mix ratio with 90+ octane gasoline.

Engine Disassembly & Assembly

Remove external components: muffler, carburetor, ignition coil, starter assembly, clutch, cylinder cover.

Cylinder & Piston: Remove cylinder bolts; lift cylinder. Inspress piston for scoring, ring wear. Measure cylinder bore (standard 44 mm).

Crankshaft & Bearings: Requires case splitting. Use puller for bearings; check seals for leaks.

Reassembly: Apply sealant to case halves; torque cylinder bolts to 10 Nm (88 in-lb). Ensure piston ring ends align with pin in groove.

Fuel System Service

Components: Fuel tank, filter, lines, carburetor, primer bulb (if equipped).

Drain fuel before service.
Inspect fuel lines for cracks; replace if hardened.
Check fuel filter; replace if dirty.
Test fuel cap vent; ensure it breathes properly.

Tip: Use ethanol-free fuel to prevent carburetor varnish and diaphragm degradation.

Ignition System

Components: Flywheel, ignition coil, spark plug, wire, stop switch.

Testing: Check spark with tester. Resistance across coil primary: 0.2–0.4 Ω; secondary: 8–12 kΩ. Air gap between coil legs and flywheel: 0.2–0.4 mm.

Flywheel removal: Use puller; do not strike with hammer. Torque nut to 40 Nm (30 ft-lb) on reassembly.

Carburetor Adjustment

Standard settings (Zama C1Q or Walbro): L (low) 1 turn out, H (high) 1 turn out, T (idle) 1 turn out.

Warm up engine fully.
Adjust L for smooth acceleration; H for max RPM (not exceeding 9600 RPM).
Set idle speed to 2700 RPM; chain must not move.
Fine-tune in cutting position under load.

WARNING! Over-leaning H screw can cause engine seizure.

Chain & Bar Maintenance

Chain sharpening: File at 30° top plate angle, 10° down angle. Maintain depth gauges 0.5–0.8 mm below cutter.

Bar: Clean groove; dress rails with flat file. Replace if worn unevenly or if groove is widened.

Sprocket: Inspert for hooking; replace if worn. Clutch drum should rotate freely.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, fuel issue	Check spark, plug; dry plug; verify fuel flow, carburetor function.
Hard starting	Compression low, air leak, carb adjustment	Test compression (≥120 psi); pressure test crankcase; adjust carb.
Lacks power	Clogged air filter, muffler screen, carb settings	Clean/replace filter; remove carbon from spark arrestor; adjust H screw.
Chain oil not flowing	Clogged oil passages, pump defective	Clean bar hole, tank filter; inspect oil pump drive, lines.
Overheating	Dull chain, lean mix, cooling fins blocked	Sharpen chain; enrich L/H screws; clean cylinder fins.
Excessive vibration	Unbalanced flywheel, loose components	Check flywheel key; tighten mounting bolts, handle screws.

Compression test: Minimum 120 psi for proper operation.

Parts List & Diagrams

Refer to Husqvarna IPL (Illustrated Parts List) for part numbers. Common replacement parts: Piston kit (503 87 47-01), Cylinder (503 87 46-01), Carburetor repair kit (530 03 61-25), Ignition coil (544 18 63-01), Fuel line (537 23 40-01).

Ordering: Use serial number (located on crankcase) for exact parts match.

Support: Husqvarna Forest & Garden Company, 1-800-487-5962; www.husqvarna.com