Homelite 46cc Chainsaw Repair Manual

The Homelite 46cc Chainsaw is a professional-grade power tool designed for demanding cutting tasks. This repair manual provides comprehensive instructions for maintenance, troubleshooting, and repair of the chainsaw's engine, fuel system, cutting assembly, and safety features. Below are key sections covering safety warnings, specifications, disassembly procedures, component replacement, and troubleshooting guides.

1. Safety Warnings & Precautions 2. Specifications & Identification 3. Tools Required 4. Engine System Repair 5. Fuel System Repair 6. Ignition System Repair 7. Cutting Assembly & Chain Brake 8. Carburetor Adjustment 9. Routine Maintenance 10. Troubleshooting Guide 11. Parts List & Diagrams

Safety Warnings & Precautions

Critical safety information to prevent injury during repair and operation.

Warning	Description
Fuel Handling	Always work in well-ventilated area away from sparks or flames. Use approved fuel containers.
Disconnect Spark Plug	Always disconnect spark plug wire before performing any repair to prevent accidental starting.
Chain Tension	Ensure chain is properly tensioned and sharp. Loose or dull chains can cause kickback.
Personal Protective Equipment	Wear safety glasses, gloves, and hearing protection during repair and operation.
Hot Surfaces	Allow engine to cool completely before handling to avoid burns.
Sharp Edges	Handle cutting chain and guide bar with care; edges are extremely sharp.

Specifications & Identification

Key specifications and model identification details.

Engine: 46cc, 2-stroke, air-cooled.
Fuel: Gasoline/Oil mix (50:1 ratio recommended).
Guide Bar Length: 16-inch, 18-inch (model dependent).
Chain Pitch: 3/8 inch.
Ignition: Electronic CDI.
Carburetor: Diaphragm type with adjustable H, L, and idle screws.
Weight: Approximately 10.5 lbs (without bar and chain).
Spark Plug: Champion RCJ7Y or equivalent, gap 0.025 inch.

Model Identification: Locate serial number plate on rear housing near handle.

Tools Required

Standard and specialty tools needed for repair.

Socket set (8mm, 10mm, 13mm).
Screwdrivers (flathead, Phillips #2).
Torx T27 driver for clutch cover.
Spark plug wrench.
Compression tester.
Carburetor adjustment tool.
Chain breaker and rivet spinner.
Feeler gauge for spark plug gap.

Note: Use genuine Homelite replacement parts for optimal performance.

Engine System Repair

Procedures for cylinder, piston, and crankshaft service.

Cylinder Inspection: Remove muffler to inspect cylinder walls for scoring.
Piston Replacement: Remove cylinder head; check ring end gap (0.010 inch).
Crankshaft Seals: Replace if leaking (common cause of lean run condition).
Compression Test: Should read 120-150 psi for healthy engine.

WARNING! Label all parts during disassembly. Use new gaskets upon reassembly.

Fuel System Repair

Fuel tank, lines, filter, and pump repair.

Drain fuel tank completely.
Replace fuel filter inside tank (use wire hook to extract).
Inspect fuel lines for cracks; replace if hardened or leaking.
Check fuel cap vent for blockage.
Prime bulb replacement: Remove carburetor cover, disconnect lines, install new bulb.

Tip: Use ethanol-free fuel to prevent carburetor varnish buildup.

Ignition System Repair

Spark plug, coil, and flywheel service.

Component	Test Procedure	Specification
Spark Plug	Check gap; replace if electrode worn	0.025 inch gap
Ignition Coil	Check resistance between terminals	Primary: 1.5-2.5 Ω, Secondary: 8-15 kΩ
Flywheel	Inspect for cracks; check key alignment	Key must be undamaged
Stop Switch	Continuity test when pressed	Should show continuity

Note: Weak spark often indicates failing ignition coil or improper air gap (0.010 inch).

Cutting Assembly & Chain Brake

Guide bar, chain, sprocket, and brake maintenance.

Chain Removal: Loosen bar nuts, remove clutch cover, lift off bar and chain.
Sprocket Inspection: Replace if teeth are hooked or worn.
Chain Brake Test: With engine off, engage brake; chain should stop immediately.
Bar Groove Cleaning: Clean bar groove with narrow screwdriver.
Chain Sharpening: Use round file matching chain pitch; maintain 30° angle.

CAUTION! Always wear cut-resistant gloves when handling chain.

Carburetor Adjustment

Procedure for tuning H (high), L (low), and idle speed screws.

Start with factory settings: H - 1 turn out, L - 1 turn out, idle - 1.5 turns out.
Warm up engine for 5 minutes.
Adjust L screw for smooth idle without chain movement.
Adjust H screw for maximum RPM (do not exceed manufacturer spec).
Fine-tune idle speed screw so chain does not move at idle.

WARNING! Over-leaning H screw can cause engine damage due to overheating.

Routine Maintenance

Regular service intervals for optimal performance.

Daily: Check chain tension, sharpness, and lubrication.
Every 10 hours: Clean air filter (replace if damaged).
Every 20 hours: Check spark plug, clean cooling fins.
Every 50 hours: Replace fuel filter, inspect fuel lines.
Seasonal: Drain fuel for storage, run carburetor dry.

Note: Always use bar and chain oil to prevent premature wear.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, flooded, fuel issue	Check spark, dry plug, verify fuel flow
Engine starts then dies	Clogged fuel filter, carburetor issue	Replace filter, clean carburetor jets
Loss of power	Clogged air filter, exhaust screen	Clean/replace filter, remove carbon from screen
Chain won't turn	Clutch worn, sprocket damaged	Inspect clutch springs, replace sprocket
Excessive vibration	Loose components, unbalanced chain	Tighten all fasteners, sharpen chain evenly
Oil leaking from bar	Overfilled, pump seal failure	Check oil level, replace pump seals if needed

Parts List & Diagrams

Reference for common replacement parts and exploded-view diagrams.

Engine Kit: Piston ring set, cylinder gasket, crankcase seals.
Fuel System: Fuel filter, primer bulb, fuel line kit.
Ignition: Spark plug, ignition coil, flywheel key.
Cutting: Guide bar, chain, drive sprocket, clutch assembly.
Carburetor: Repair kit (includes diaphragms, gaskets, needle valve).

Ordering: Use model and serial number when ordering parts. Diagrams available at www.homelite.com.

Service Support: 1-800-242-4672; www.homelite.com