Makita Chainsaw UC3520A Manual

The Makita UC3520A is a 35cc 2-stroke gasoline-powered chainsaw designed for professional and heavy-duty cutting tasks. It features a robust engine, automatic oiler, anti-vibration system, safety chain brake, tool-less chain tensioning, and easy-start technology. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 35cc 2-stroke engine, 16-inch guide bar, automatic chain oiler, safety chain brake, anti-vibration handles, tool-less chain tensioner, decompression valve for easy starting.

Safety Information

Read all instructions before use. Always wear protective gear.

1. Personal Protective Equipment (PPE): Wear safety glasses, hearing protection, gloves, chainsaw chaps, and steel-toe boots.
2. Work Area Safety: Clear area of obstacles and bystanders. Ensure secure footing.
3. Kickback Prevention: Hold saw firmly with both hands; avoid tip contact.
4. Chain Brake: Test before each use; engage when carrying or not cutting.

WARNING! Never operate chainsaw with one hand. Keep hands away from moving chain. Do not operate while tired or under influence.

Assembly & Preparation

Unpack and inspect contents. Assemble guide bar and chain.

1. Attach Guide Bar: Remove side cover, position bar over studs, align chain drive links with sprocket.
2. Install Chain: Place chain over bar with cutting edges facing forward, ensure proper direction.
3. Tension Chain: Use tool-less tensioner to adjust until chain snaps back when pulled from bar.
4. Fuel Mix: Use 50:1 gasoline to 2-stroke oil mixture (recommended: Makita 2-stroke oil).
5. Fill Tanks: Add fuel mix to fuel tank and bar/chain oil to oil tank.

CAUTION! Use only recommended oil and fuel. Do not mix near open flames.

Specifications

• Engine Displacement: 35 cc
• Power Output: 1.8 kW (2.4 HP)
• Guide Bar Length: 16 inches (40 cm)
• Chain Speed: 20.5 m/s
• Fuel Tank Capacity: 0.55 L
• Oil Tank Capacity: 0.26 L
• Weight (without bar/chain): 4.8 kg
• Sound Pressure Level: 112 dB(A)
• Vibration Level: Front handle 3.2 m/s², Rear handle 4.5 m/s²
• Warranty: 1 year commercial, 2 years private

Controls and Components

Main controls: Throttle trigger, throttle trigger lockout, stop switch, choke lever, decompression valve, chain brake lever, primer bulb.

Components: Front handle with chain brake, rear handle with throttle, air filter cover, spark plug, muffler, side cover with tensioner, fuel cap, oil cap.

Operation: Throttle trigger lockout must be depressed before squeezing throttle. Chain brake lever (front handle) stops chain when engaged. Decompression valve reduces cylinder pressure for easier starting.

Starting & Stopping

Starting Procedure (Cold Engine):

1. Place chainsaw on flat ground, clear of debris.
2. Engage chain brake by pushing lever forward.
3. Press decompression valve (if equipped).
4. Move choke lever to FULL CHOKE position.
5. Press primer bulb 5-6 times until fuel is visible.
6. Pull starter rope briskly until engine fires.
7. Move choke lever to HALF CHOKE, pull until engine starts.
8. Allow engine to warm up, then disengage chain brake.

Stopping: Release throttle, press stop switch to OFF position.

Tip: For warm start, use HALF CHOKE or no choke.

Operation Guidelines

Proper cutting techniques ensure safety and efficiency.

1. Felling Trees: Plan escape path; make notch cut and back cut; use wedges if needed.
2. Limbing: Stand uphill; cut from top of log; avoid cutting with tip.
3. Bucking: Support log; cut from top; beware of binding.
4. Kickback Zone: Avoid contact with upper quarter of guide bar tip.
5. Chain Oiling: Check oil flow regularly; adjust oiler if needed.

WARNING! Always cut at full throttle. Do not cut above shoulder height.

Maintenance & Cleaning

Regular maintenance ensures optimal performance and longevity.

• Daily: Clean air filter, check chain tension, inspect guide bar for wear.
• Weekly: Clean spark arrestor screen, check spark plug gap (0.025 inch).
• Monthly: Clean cooling fins, check fuel filter, replace bar/chain oil.
• As Needed: Sharpen chain, replace worn sprocket, clean carburetor.

CAUTION! Disconnect spark plug before performing maintenance. Use only Makita replacement parts.

Chain Sharpening & Replacement

Sharp chain improves cutting and reduces kickback risk.

1. Secure chainsaw: Use vise to hold bar.
2. File Size: Use 5/32 inch round file for 3/8 inch pitch chain.
3. Filing Angle: Maintain 30-degree angle; file each cutter equally.
4. Depth Gauges: File down to 0.025 inch below cutter top.
5. Replacement: Replace chain when cutters are worn beyond repair or damaged.

Tip: Rotate file regularly to prevent uneven wear.

Storage

Proper storage prevents fuel system issues and corrosion.

1. Empty fuel tank or add fuel stabilizer.
2. Run engine until carburetor is dry.
3. Remove chain, clean and oil it; store separately.
4. Clean entire saw; apply light oil to metal surfaces.
5. Store in dry, cool place away from children.

CAUTION! Never store with fuel in tank for more than 30 days without stabilizer.

Troubleshooting

Service: For technical support, contact Makita at 1-800-4-MAKITA or visit www.makitatools.com.