Husqvarna Chainsaw Workshop Manual 365

The Husqvarna Chainsaw Model 365 is a professional-grade chainsaw designed for demanding forestry and arborist work. This workshop manual provides comprehensive technical information for service technicians, including detailed specifications, maintenance procedures, troubleshooting guides, repair instructions, and safety protocols. Below are key sections covering safety, technical data, engine systems, fuel system, ignition system, cutting equipment, maintenance schedules, and common repairs.

1. Safety Information & Warnings 2. Technical Specifications 3. Engine Overview & Components 4. Fuel System & Carburetor 5. Ignition System & Electrical 6. Chain & Bar Assembly 7. Maintenance Schedule 8. Disassembly & Assembly 9. Troubleshooting Guide 10. Torque Specifications 11. Parts Diagrams & List

Safety Information & Warnings

Critical safety procedures must be followed to prevent serious injury or death during maintenance and repair.

Hazard	Precaution
Fuel & Fire	Work in well-ventilated area; no smoking or open flames near fuel.
Sharp Components	Always wear cut-resistant gloves when handling chain, bar, or cutter teeth.
Hot Surfaces	Allow engine and muffler to cool completely before disassembly.
Spring-Loaded Parts	Use proper tools; be aware of stored energy in starter recoil and AV mounts.
Electrical Shock	Disconnect spark plug wire before any service to prevent accidental starting.
Chemical Exposure	Use gloves and eye protection when handling fuel, oil, or cleaning solvents.
Lifting & Support	Secure saw in vise or holding fixture; do not work on unstable surfaces.
High-Pressure Fuel	Depressurize fuel system (if applicable) before opening fuel lines.

Technical Specifications

Model: Husqvarna 365
Engine Type: 2-stroke, single cylinder, air-cooled
Displacement: 65.1 cc (3.97 cu. in.)
Power Output: 4.2 kW (5.6 hp) @ 9000 rpm
Fuel Tank Capacity: 0.85 L (0.22 US gal)
Oil Tank Capacity: 0.40 L (0.11 US gal)
Idle Speed: 2700 rpm
Maximum Power Speed: 9000 rpm
Ignition System: Electronic, semi-transistorized
Spark Plug: Champion RCJ7Y or equivalent, gap 0.5 mm (0.020")
Carburetor: Walbro HDA or Zama C1M, adjustable H, L, T
Recommended Fuel: Unleaded gasoline min 90 octane mixed with 2-stroke oil at 50:1 ratio (Husqvarna HP or equivalent)
Bar Length Range: 40 cm (16") to 76 cm (30")
Chain Pitch: 3/8" or .325" (depending on configuration)
Weight (Powerhead): 6.7 kg (14.8 lbs) without bar and chain

Engine Overview & Components

Cylinder, piston, crankshaft, connecting rod, bearings, seals, and crankcase assembly.

Cylinder: Chrome-plated bore; inspect for scoring, transfer, or glaze.
Piston & Rings: Measure ring end gap and piston skirt clearance.
Crankshaft: Check runout and big-end rod bearing play.
Crankcase: Split case to replace crankshaft seals or bearings.
Muffler & Spark Arrestor: Clean regularly to prevent carbon buildup and overheating.

WARNING! Always replace cylinder and piston as a matched set if either is damaged. Use genuine Husqvarna gaskets during reassembly.

Fuel System & Carburetor

Fuel tank, filter, lines, pump, carburetor, and adjustment screws.

Remove carburetor: Disconnect fuel lines, throttle linkage, and mounting nuts.
Disassembly: Remove diaphragms, gaskets, needle valve, and jets. Clean in ultrasonic cleaner.
Inspection: Check diaphragms for cracks or stiffness; replace fuel filter and impulse line if cracked.
Adjustment (H, L, T screws): Initial setting - turn H & L screws gently clockwise to seat, then back out H 1 turn, L 1.25 turns. Fine-tune for smooth acceleration and idle.
Pressure/Vacuum Test: Use pump to check for leaks in crankcase seals and intake manifold.

CAUTION! Do not overtighten adjustment screws. Use a limiter cap tool if required by emissions regulations.

Ignition System & Electrical

Spark plug, ignition coil (module), flywheel, stop switch, and wiring harness.

Spark Test: Remove plug, ground electrode to cylinder, pull starter - look for strong blue spark.
Coil Air Gap: Set between 0.2-0.3 mm (0.008-0.012") using feeler gauge.
Flywheel: Check key and taper for damage; torque nut to 40-50 Nm (30-37 ft-lbs).
Stop Switch: Test continuity; switch should be open (infinite resistance) when off, closed (0 ohms) when on.
Wiring: Inspect for chafing, breaks, or poor connections at coil and switch.

Chain & Bar Assembly

Guide bar, saw chain, sprocket (rim or spur), clutch, oil pump, and tensioning system.

Bar Inspection: Check for straightness, groove wear, and burrs on rails. Dress with flat file if needed.
Chain Sharpening: Maintain correct filing angles (30° top plate, 10° top plate side angle). Depth gauges must be lowered proportionally.
Sprocket: Replace rim sprocket when worn or damaged; check clutch drum bearing.
Clutch: Inspect shoes for wear and springs for fatigue. Clean centrifugal clutch assembly.
Oil Pump: Test output; adjust (if adjustable) or replace if clogged or worn.
Chain Tension: Adjust so chain snaps back when lifted from bar; not sagging but not tight.

Tip: Always match chain pitch and gauge to bar and sprocket. Rotate bar regularly for even wear.

Maintenance Schedule

Interval (Operating Hours)	Task
Daily / Before Use	Check chain tension, sharpness, bar condition. Check fuel/oil levels. Clean air filter if needed. Inspect for loose fasteners.
10 Hours	Clean air filter thoroughly. Check spark plug condition and gap. Clean cooling fins and muffler area.
20 Hours	Replace fuel filter. Clean spark arrestor screen. Inspect clutch and sprocket.
50 Hours	Replace spark plug. Clean carburetor intake and check diaphragms. Check all fuel lines for cracks.
100 Hours	Decarbonize cylinder head and exhaust port. Check piston through exhaust port. Replace crankcase seals if suspect. Check ignition coil air gap.
Annual / 200 Hours	Pressure/vacuum test engine. Replace impulse line and intake manifold gasket. Inspect anti-vibration mounts. Full carburetor rebuild kit if necessary.

Disassembly & Assembly

Step-by-step procedures for major component removal and installation.

Remove Top Cover & Air Filter Cover: Unsnap or remove screws.
Remove Fuel Tank: Drain fuel, disconnect lines, remove mounting screws.
Remove Cylinder: Remove muffler, decomp valve (if equipped), cylinder bolts. Lift cylinder off carefully.
Separate Crankcase: Remove all screws, heat case halves evenly with heat gun, tap with plastic mallet to separate. Do not pry.
Reassembly: Use new gaskets and seals. Apply thread locker to crankcase screws. Torque in crisscross pattern to specification.
Piston Installation: Ring ends must align with pins in ring grooves. Use piston ring compressor or strap. Arrow on piston crown must point toward exhaust port.

WARNING! Mark all components and take photos during disassembly. Keep work area clean to prevent contamination.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine will not start	No spark, flooded, fuel issue, compression low	Check spark, plug wetness. Dry plug, choke off, pull with throttle open. Check fuel filter, lines, carb. Test compression (should be >120 psi).
Engine starts but dies	Clogged fuel filter, dirty carb, bad fuel, air leak	Replace fuel filter. Clean carburetor jets and diaphragms. Use fresh fuel mix. Pressure test for air leaks at seals/manifold.
Lacks power, bogs under load	Clogged air filter, carb adjustment, exhaust blocked, fuel restriction	Clean/replace air filter. Adjust H needle. Clean spark arrestor and muffler. Check fuel tank vent.
Engine runs unevenly, surges	Air leak, dirty carb, incorrect L adjustment	Pressure test engine. Clean carb, especially low-speed circuit. Adjust L screw for smooth idle.
Chain does not stop when idling (clutch drag)	Idle speed too high, worn clutch springs, gummed clutch	Adjust idle speed to 2700 rpm. Replace clutch springs. Clean clutch drum and shoes with solvent.
Excessive vibration	Unbalanced chain, bent bar, worn AV mounts, damaged crank	Sharpen chain evenly. Check bar straightness. Replace anti-vibration mounts. Inspect crankshaft runout.
Chain oil not flowing	Empty oil tank, clogged oil passages, faulty pump, wrong oil viscosity	Fill tank. Clean bar oil holes and tank filter. Test pump output. Use recommended bar oil.

Torque Specifications

Critical fastener torques (use calibrated torque wrench).

Component	Torque (Nm)	Torque (ft-lbs)
Cylinder bolts (M6)	10-12	7.5-9
Crankcase screws (M5)	6-8	4.5-6
Flywheel nut	40-50	30-37
Clutch (left-hand thread)	35-45	26-33
Spark plug	20-25	15-18
Guide bar nuts	9-11	6.5-8
Muffler bolts	8-10	6-7.5
Carburetor mounting nuts	4-5	3-3.7

Parts Diagrams & List

Reference exploded-view diagrams for ordering genuine Husqvarna replacement parts.

Cylinder Group: Piston, rings, wrist pin, circlips, cylinder, gasket.
Crankshaft Group: Crankshaft, main bearings, seals, connecting rod.
Carburetor Group: Complete carburetor, repair kit, fuel line, filter.
Ignition Group: Ignition module, flywheel, spark plug, stop switch.
Clutch & Sprocket Group: Clutch assembly, drum, rim sprocket, bearing.
Oil Pump Group: Oil pump, gears, hose, filter.
AV & Handle Group: Anti-vibration mounts, handle, throttle trigger, lockout.
Bar & Chain Group: Guide bar, saw chain, drive sprocket, tensioner.

Note: Always use Husqvarna part numbers when ordering. Non-genuine parts may affect performance and safety.

Service Support: For technical assistance or parts, contact Husqvarna authorized service center or visit www.husqvarna.com.