Stihl FS 44 Parts Manual

The Stihl FS 44 is a lightweight, easy-to-handle trimmer designed for residential use. This parts manual provides detailed diagrams and part numbers for the FS 44 brushcutter/string trimmer, including the engine, cutting head, drive shaft, handle assembly, and fuel system. Below are key sections for identification, engine components, cutting attachments, drive train, controls, and ordering information.

Identification & Specifications

Key identifiers: Model FS 44, Engine type, serial number location.

Feature	Description
Model	FS 44 Brushcutter / String Trimmer
Engine Type	2-stroke, single-cylinder, air-cooled
Displacement	27.2 cc (1.66 cu. in.)
Power Output	Approx. 0.8 kW (1.1 hp)
Fuel/Oil Mix	50:1 (STIHL HP Ultra oil)
Cutting Attachment	STIHL PolyCut head (standard), optional blade
Drive	Flexible drive shaft
Weight (without cutter)	Approx. 4.6 kg (10.1 lbs)
Serial Number Location	On engine housing near muffler
Ignition System	Electronic, capacitor discharge (CDI)

Engine Assembly & Components

Cylinder, piston, crankshaft, muffler, and engine housing parts.

1. Cylinder & Piston Assembly: Includes cylinder, piston, rings, wrist pin, circlips.
2. Crankshaft & Bearings: Crankshaft assembly, main bearings, seals.
3. Muffler & Spark Arrestor: Muffler housing, spark arrestor screen, gasket.
4. Engine Housing: Two-piece clamshell housing, screws, vibration dampeners.
5. Crankcase & Gaskets: Crankcase halves, gaskets, crankcase screws.

WARNING! Disconnect spark plug before servicing engine components. Use genuine STIHL parts.

Cutting Attachments & Guard

PolyCut head, blades, guard, and attachment hardware.

1. PolyCut Head: Spool, spring, bump knob, housing, retaining ring.
2. Blade Options: Circular grass blade, metal brush knife (optional).
3. Cutting Attachment Guard: Guard assembly, mounting hardware.
4. Attachment Nut & Washer: Special nut and washer for securing head/blade.
5. Drive Square: Male drive square on gearbox for attachment.

CAUTION! Ensure guard is properly installed. Use correct attachment for material.

Drive Shaft & Gearbox

• Flexible Drive Shaft: Inner cable, outer casing, end fittings.
• Gearbox Assembly: Bevel gears, housing, seals, grease.
• Output Shaft: Shaft, bearing, seal, drive square.
• Gearbox Mounting: Clamps, screws to attach to shaft tube.
• Lubrication: Use STIHL gearbox grease (part # 0781 400 2001).

Handle & Control Assembly

Loop handle, throttle trigger, lockout, throttle cable, and control module.

Handle: Loop handle, mounting clamp, screws, vibration elements.

Controls: Throttle trigger, throttle lockout (interlock), stop switch, wire harness.

Throttle Cable: Cable assembly, adjuster, fittings to carburetor.

Carrying Harness: Attachment points on handle and shaft.

Fuel System & Tank

Fuel tank, cap, filter, lines, carburetor, and primer.

1. Fuel Tank: Polyethylene tank, mounting straps, grommets.
2. Fuel Cap: Venting cap with tether.
3. Fuel Filter & Lines: In-tank filter, fuel line, return line.
4. Carburetor: Zama or Walbro carburetor, gaskets, adjustment screws.
5. Primer Bulb: Primer assembly, hoses, check valves.

Tip: Use only clean, fresh fuel mix. Replace fuel lines periodically.

Air Filter & Cooling System

Air filter, cover, cooling fins, and fan wheel.

1. Air Filter: Foam filter element, may include pre-filter.
2. Filter Cover: Cover, retaining screw or latch.
3. Cooling Fins: On cylinder head, keep clean of debris.
4. Fan Wheel: On flywheel, draws air over cylinder.
5. Air Intake Cover: Covers intake port to carburetor.

WARNING! Never operate without air filter. Clean filter regularly.

Ignition System

Spark plug, ignition module, flywheel, stop switch wire.

Spark Plug: NGK BPMR7A or equivalent, gap 0.5 mm (0.020 in).

Ignition Module (CDI): Mounted near flywheel, with wiring harness.

Flywheel: Magnets, keyway, fan blades, mounting nut.

Stop Switch Wire: Connects from handle switch to ignition module.

Starter Assembly

Starter housing, rope, pulley, spring, pawls.

1. Starter Housing: Plastic housing, screws to engine cover.
2. Starter Rope & Handle: Rope, handle, knot.
3. Rewind Spring & Pulley: Spring, pulley, retaining clip.
4. Pawls & Springs: Engagement pawls, springs for flywheel engagement.
5. Starter Cover: Decal, air inlet slots.

CAUTION! Spring under tension. Use care when disassembling.

Fasteners & Hardware

Screws, nuts, washers, clips specific to FS 44.

Part Type	Description	Common Sizes
Housing Screws	Self-tapping for plastic	Various lengths
Muffler Screws	Heat-resistant	M5 x 25 mm
Carburetor Screws	Flange head	M4 x 16 mm
Circlips	For piston pin	8 mm
Retaining Rings	For cutting head	Snap ring

Parts Ordering & Exploded Views

Use exploded diagrams with reference numbers to order parts.

Symptom	Common Part Needed	Part Number Example
Engine won't start	Spark plug, fuel filter	Spark plug: 0000 400 1300
Loss of power	Air filter, fuel line	Air filter: 0000 350 3501
Cutting head won't feed	Spool, spring	Spool: 0000 350 3505
Excessive vibration	Drive shaft, bearings	Drive shaft: 4130 160 2000
Throttle sticking	Throttle cable	Cable: 4130 160 2100

Ordering: Contact STIHL dealer with model and serial number. Diagrams available in STIHL repair manual.

Service: Authorized STIHL servicing dealers only. Visit www.stihlusa.com for dealer locator.