Husqvarna 125BT Parts Manual

The Husqvarna 125BT is a professional-grade backpack leaf blower designed for demanding commercial and residential use. This parts manual provides detailed information on all components, assembly diagrams, part numbers, and ordering information for maintenance and repair. Below are key sections covering identification, exploded views, parts lists, ordering procedures, and warranty information.

1. Product Identification 2. Exploded View Diagrams 3. Parts List & Descriptions 4. Technical Specifications 5. Assembly Instructions 6. Maintenance Parts 7. Engine Components 8. Blower Tube & Nozzle 9. Harness & Controls 10. Ordering Information 11. Troubleshooting Parts Issues

Product Identification

Locate your model and serial number for accurate parts identification. Key identification labels: Model plate on engine housing, Serial number sticker on frame.

Label Location	Information
Engine Housing (Right Side)	Model: 125BT, Engine Type, Serial Number
Frame (Near Harness)	Manufacturing Date, Part Number Prefix
Blower Tube	Tube Diameter, Part Number
Fuel Tank	Capacity, Material Specification

Exploded View Diagrams

Detailed assembly diagrams showing component relationships.

Main Assembly: Frame, engine, blower housing, harness.
Engine Assembly: Cylinder, piston, carburetor, ignition system.
Air System: Impeller, fan housing, intake cover, tubes.
Control Assembly: Throttle cable, control lever, kill switch.
Harness Assembly: Shoulder straps, waist belt, padding.

WARNING! Use diagrams only with correct part numbers. Disconnect spark plug before disassembly.

Parts List & Descriptions

Complete numerical parts listing with descriptions and quantities.

Frame Group: Main frame, mounting brackets, hardware.
Engine Group: 2-stroke engine, air filter, muffler, spark plug.
Blower Group: Impeller, fan housing, intake cover, seals.
Tube Group: Main tube, curved tube, nozzle, locking collars.
Control Group: Throttle lever, cable, kill switch, wiring.
Harness Group: Shoulder straps, waist belt, padding, buckles.
Fuel System: Tank, cap, fuel line, filter, carburetor.
Air Filter: Filter element, cover, pre-filter.

Technical Specifications

Engine: 2-stroke, 28.1cc, air-cooled.
Airflow: 425 CFM at nozzle.
Air Speed: 170 MPH maximum.
Fuel Capacity: 1.9 liters (0.5 gallons).
Dry Weight: 10.1 kg (22.3 lbs).
Sound Level: 70 dB(A) at operator position.
Tube Diameter: 65 mm (2.56 inches).
Vibration Level: 3.5 m/s² front, 2.5 m/s² rear.

Assembly Instructions

Step-by-step assembly for replacement parts.

Tube Assembly: Connect curved tube to main housing, secure with locking collar. Attach nozzle to curved tube.

Harness Adjustment: Thread shoulder straps through buckles, adjust length for operator comfort. Secure waist belt.

Control Installation: Route throttle cable through guides, connect to carburetor. Adjust cable tension.

Air Filter Replacement: Remove cover, replace filter element, ensure seal is properly seated.

Maintenance Parts

Common replacement parts for routine maintenance.

Part Description	Part Number	Replacement Interval
Air Filter Element	505 87 67-01	Every 25 hours
Spark Plug	BP7ES (NGK)	Every 100 hours
Fuel Filter	501 87 65-01	Every 50 hours
Impeller	537 33 70-01	As needed
Fan Housing	537 33 71-01	As needed
Harness Strap Set	537 33 72-01	As needed

Engine Components

Detailed engine parts breakdown.

Cylinder & Piston: Cylinder, piston, rings, wrist pin.
Crankcase: Crankcase halves, crankshaft, bearings.
Carburetor: Zama C1U carburetor, diaphragm, gaskets.
Ignition System: Ignition coil, flywheel, spark plug wire.
Muffler: Muffler assembly, spark arrestor, gasket.
Recoil Starter: Starter assembly, rope, pulley, spring.

CAUTION! Engine parts require special tools and expertise. Consult authorized service center.

Blower Tube & Nozzle

Air delivery system components.

Main Tube: 65mm diameter aluminum tube.
Curved Tube: 90-degree curved aluminum tube.
Nozzle: Concentrator nozzle for focused airflow.
Locking Collars: Quick-release locking mechanisms.
Rubber Coupler: Vibration dampening coupler.

Tip: Inspect tubes regularly for dents or damage affecting airflow.

Harness & Controls

Operator interface and carrying system.

Harness: Padded shoulder straps, waist belt, quick-adjust buckles, lumbar support.

Controls: Throttle lever with lock, cruise control button, kill switch, choke lever.

Vibration Isolation: Rubber mounts between engine and frame.

Ordering Information

How to order genuine Husqvarna parts.

Identify part number from this manual.
Contact authorized Husqvarna dealer with model and serial number.
Use Husqvarna Parts Finder online at www.husqvarna.com.
For warranty claims, provide proof of purchase and serial number.

WARNING! Use only genuine Husqvarna parts to maintain performance and warranty.

Troubleshooting Parts Issues

Symptom	Possible Part Issue	Corrective Action
Reduced airflow	Worn impeller, clogged tube	Inspect and replace impeller; clean tube interior.
Engine won't start	Fouled spark plug, clogged fuel filter	Replace spark plug; install new fuel filter.
Excessive vibration	Damaged fan, loose mounting	Replace fan assembly; tighten all mounts.
Harness discomfort	Worn padding, misadjusted straps	Replace padding; readjust strap length.
Throttle sticking	Worn cable, dirty lever mechanism	Replace throttle cable; clean and lubricate lever.

Service: Authorized Husqvarna service centers only. Contact 1-800-487-5962 or www.husqvarna.com.