McCulloch Mac Cat Chainsaw Manual

The McCulloch Mac Cat is a lightweight, gas-powered chainsaw designed for homeowners and DIY enthusiasts. It features a reliable 2-stroke engine, automatic oiling system, 16-inch guide bar, inertia-activated chain brake, easy-start system, and anti-vibration handles. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 42cc 2-stroke engine, 16-inch Oregon bar and chain, automatic chain oiler, inertia chain brake, decompression valve, primer bulb, anti-vibration system.

Safety Information

Always wear protective gear: helmet, eye protection, hearing protection, gloves, chainsaw chaps, and steel-toe boots.

1. Clear work area of obstacles and bystanders.
2. Check chain tension and sharpness before each use.
3. Engage chain brake when starting or carrying saw.
4. Use two hands on handles at all times during operation.
5. Never operate above shoulder height or on a ladder.

WARNING! Gasoline is highly flammable. Refuel only when engine is cool, outdoors, and away from ignition sources.

Assembly & Setup

Unpack and inspect contents. Assembly requires attaching guide bar and chain, filling fluids.

1. Attach guide bar: Loosen bar nuts, position bar over studs, align chain drive links with sprocket.
2. Install chain: Place chain over bar with cutting teeth facing forward on top.
3. Adjust tension: Tighten bar nuts hand-tight, use adjustment screw to set proper tension (0.25" pull from bar).
4. Final tighten: Hold bar tip up, fully tighten bar nuts.
5. Fill fluids: Mix fuel (see Section 6), fill oil tank with bar & chain oil.

CAUTION! Chain must move freely; overtightening can damage bar and engine.

Specifications

• Model: McCulloch Mac Cat CS 4016
• Engine Type: 2-stroke, single cylinder, air-cooled
• Power Output: 2.1 HP @ 9000 RPM
• Max Engine Speed: 12,500 RPM
• Fuel Mix Ratio: 40:1 (unleaded gasoline to 2-stroke oil)
• Recommended Fuel: 89 octane minimum, ethanol-free preferred
• Bar Oil: SAE 30 or dedicated chainsaw bar oil
• Sound Power Level: 112 dB(A)
• Vibration Level: 4.2 m/s² (front handle), 6.8 m/s² (rear handle)
• Warranty: 2 years residential use

Controls and Components

Main controls located on top and rear handle. Front Handle: Chain brake/hand guard, throttle lockout. Rear Handle: Throttle trigger, ignition switch, choke control, primer bulb.

Labels: STOP (ignition switch), CHOKE, PRIME, THROTTLE LOCKOUT.

Operation: Press throttle lockout while pulling trigger to engage chain. Push hand guard forward to activate chain brake. Choke for cold starts, primer to fuel carburetor.

Fuel & Oil Mixing

Use fresh unleaded gasoline (89 octane min.) and JASO FD or ISO-L-EGD certified 2-stroke oil.

1. Mix ratio: 40:1 (3.2 oz oil per 1 gallon gasoline).
2. Use clean mixing container; add oil first, then gasoline.
3. Shake gently to blend.
4. Fill fuel tank through filtered funnel.
5. Fill oil tank with bar & chain oil (SAE 30).

Tip: Do not use gasoline older than 30 days. Add fuel stabilizer for storage.

Starting & Operation

Starting procedure (cold engine):

1. Place saw on flat ground, clear of debris.
2. Engage chain brake by pushing hand guard forward.
3. Move ignition switch to ON (I) position.
4. Set choke lever to FULL CHOKE.
5. Press primer bulb 5-6 times until fuel is visible.
6. Pull starter rope briskly 2-3 times until engine 'pops'.
7. Move choke to HALF position.
8. Pull starter until engine starts.
9. Allow to warm up 30 seconds, then disengage chain brake.

WARNING! Never drop-start or start with chain brake disengaged. Keep firm footing.

Chain Maintenance

Daily maintenance ensures optimal performance and safety.

1. Chain sharpening: Use 5/32" round file, maintain 30° cutting angle, 10° top plate angle.
2. Depth gauges: File to 0.025" below cutter with flat file and gauge.
3. Bar maintenance: Clean bar groove weekly, flip bar monthly for even wear.
4. Sprocket inspection: Replace drive sprocket every 2-3 chains.
5. Oil flow check: Run saw at high idle over cardboard; oil line should appear.

CAUTION! Wear gloves when handling chain. Always disconnect spark plug before maintenance.

Storage & Winterization

Prepare saw for storage exceeding 30 days.

1. Drain fuel tank and run engine until it stalls.
2. Remove spark plug, add 1 tsp of 2-stroke oil through hole.
3. Pull starter slowly 2-3 times to coat cylinder.
4. Replace spark plug.
5. Clean entire saw, apply light oil to bar and chain.
6. Store in dry place, cover to prevent dust.

CAUTION! Never store with fuel in tank; gumming can damage carburetor.

Warranty Information

McCulloch Limited Warranty: 2 years for residential use from date of purchase. Covers defects in materials/workmanship. Does not cover normal wear, misuse, lack of maintenance, or commercial use. Proof of purchase required. For warranty service, contact authorized service center or 1-800-521-8559. Keep this manual and receipt.

Troubleshooting

Spark Plug: NGK BPMR7A gap 0.020" (0.5 mm). Replace annually.

Service: 1-800-521-8559; www.mcculloch.com