John Deere CS 81 Chainsaw Owners Manual

The John Deere CS 81 is a professional-grade chainsaw designed for demanding cutting tasks. It features a powerful 81cc engine, automatic oiling system, anti-vibration handles, safety chain brake, and a durable Oregon bar and chain. Below are key sections for safety, features, assembly, operation, maintenance, troubleshooting, and specifications.

Features at a Glance

Key components: 81cc 2-stroke engine, 20-inch Oregon bar and chain, Automatic chain oiler, Inertia-activated chain brake, Anti-vibration system, Decompression valve, Side-access chain tensioner.

Safety Information

Read and understand all safety warnings before operation.

1. Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, gloves, chainsaw chaps/pants, and sturdy boots.
2. Kickback Zone: Avoid contact with the upper quadrant of the bar tip.
3. Clear Work Area: Ensure no obstacles or people within 15 feet.
4. Secure Workpiece: Never cut with the saw held above shoulder height.
5. Carrying: Engage chain brake and carry with bar pointing rearward.

WARNING! Failure to follow safety instructions can result in serious injury or death. The chain brake is a safety device; test it before each use.

Assembly & Preparation

Unpack and inspect contents. Assemble bar and chain.

1. Attach Guide Bar & Chain: Place bar over studs, loop chain over sprocket and bar, adjust tension with side knob.
2. Fill Fuel: Use fresh 50:1 gasoline/oil mixture (89 octane minimum).
3. Fill Bar & Chain Oil: Use quality chainsaw bar oil.
4. Check Controls: Ensure throttle trigger, throttle lockout, and chain brake function properly.

CAUTION! Fuel is highly flammable. Refuel in a well-ventilated area with engine off and cool.

Specifications

• Model: John Deere CS 81
• Engine Type: 2-stroke, air-cooled
• Displacement: 81 cc
• Power Output: 5.8 HP
• Fuel Mix Ratio: 50:1 (Unleaded gasoline to 2-stroke oil)
• Idle Speed: 2,800 RPM
• Maximum Power Speed: 9,500 RPM
• Sound Pressure Level: 112 dB(A)
• Vibration Level: Front Handle: 4.5 m/s², Rear Handle: 5.2 m/s²
• Weight (dry): 15.2 lbs (6.9 kg)
• Warranty: 2-year limited warranty for non-commercial use.

Controls and Components

Main Controls: Front Handle with Chain Brake, Rear Handle with Throttle Trigger, Throttle Lockout, Master Control Lever (Choke/Start/Run), Decompression Valve Button.

Master Control Lever Positions: - STOP (0): Engine off. - CHOKE (rabbit symbol): For cold starting. - START (vertical line): For warm starting or after choke. - RUN (horizontal line): Normal operation.

Other Features: Side-access chain tensioner, Spark arrestor muffler, Fuel primer bulb (on some models), Visible fuel and oil level windows.

Fuel & Oil

Fuel: Use 89+ octane unleaded gasoline mixed with a high-quality 2-stroke engine oil at a 50:1 ratio. Do not use fuel older than 60 days.

Bar & Chain Oil: Use genuine John Deere bar & chain oil or equivalent. In cold weather (< 32°F / 0°C), use winter-grade oil.

1. Fill fuel tank to 80% capacity to allow for expansion.
2. Fill oil tank completely.
3. Wipe away any spills before starting.

Tip: The automatic oiler rate is adjustable via a screw near the oil tank. Increase for heavy cutting, decrease for light duty.

Operation

Starting Procedure (on ground):

1. Engage chain brake by pushing front handle forward.
2. Press decompression valve (if equipped).
3. Set Master Control to CHOKE (cold) or START (warm).
4. Place saw on firm ground, hold rear handle with right foot.
5. Pull starter cord briskly 3-5 times until engine "pops".
6. Move Master Control to START and pull until engine starts.
7. Blip throttle to disengage fast idle. Release chain brake to begin cutting.

Cutting Techniques: Use full throttle when cutting. Let the saw do the work; do not force it. Plan your cut to avoid pinching the bar.

WARNING! Always operate with both hands. Be aware of kickback. Never cut with the tip of the bar.

Maintenance Schedule

Daily/Before Use: Check chain tension, sharpness, and brake function. Check fuel/oil levels. Clean air filter. Inspect for loose parts.

Weekly/10 Hours: Clean spark arrestor screen. Check spark plug condition and gap (0.020 in / 0.5 mm). Clean cooling fins.

Monthly/50 Hours: Clean fuel filter. Check clutch and sprocket wear. Grease drive sprocket bearing (if applicable).

Annually/Storage: Drain fuel system. Perform complete inspection. Replace worn components (bar, chain, sprocket, filters).

Chain Sharpening & Tensioning

Sharpening: Use a round file matching chain pitch (.404"). Maintain 30° cutting angle and 10° top plate angle. File all cutters to equal length. Depth gauges should be filed to 0.025 in (0.65 mm) below cutter top plate.

Tensioning: Chain should be snug against bar but pull freely by hand. Adjust with side tensioner when saw is cold. Re-check tension after 5 minutes of operation.

CAUTION! Always wear gloves when handling chain. A loose chain can derail; an overtightened chain can damage the engine.

Storage

For storage over 30 days:

1. Drain fuel tank and run engine until it stops to clear carburetor.
2. Drain bar and chain oil tank.
3. Remove chain, clean in solvent, dry, and coat with oil.
4. Clean entire saw, especially cooling fins and air filter.
5. Store in a dry, dust-free place, with bar and chain separately.

CAUTION! Old fuel can gum up the carburetor. Never store saw with fuel in the tank.

Troubleshooting

Service: For major repairs, contact an authorized John Deere dealer. Use only genuine John Deere parts.

Support: 1-800-537-8233 (USA) or visit www.JohnDeere.com